Detailed changes
@@ -81,6 +81,19 @@
revision = "aa810b61a9c79d51363740d207bb46cf8e620ed5"
version = "v1.2.0"
+[[projects]]
+ digest = "1:2e3c336fc7fde5c984d2841455a658a6d626450b1754a854b3b32e7a8f49a07a"
+ name = "github.com/google/go-cmp"
+ packages = [
+ "cmp",
+ "cmp/internal/diff",
+ "cmp/internal/function",
+ "cmp/internal/value",
+ ]
+ pruneopts = "UT"
+ revision = "3af367b6b30c263d47e8895973edcca9a49cf029"
+ version = "v0.2.0"
+
[[projects]]
digest = "1:c79fb010be38a59d657c48c6ba1d003a8aa651fa56b579d959d74573b7dff8e1"
name = "github.com/gorilla/context"
@@ -382,6 +395,20 @@
revision = "5420a8b6744d3b0345ab293f6fcba19c978f1183"
version = "v2.2.1"
+[[projects]]
+ digest = "1:225f565dc88a02cebe329d3a49d0ca125789091af952a5cc4fde6312c34ce44d"
+ name = "gotest.tools"
+ packages = [
+ "assert",
+ "assert/cmp",
+ "internal/difflib",
+ "internal/format",
+ "internal/source",
+ ]
+ pruneopts = "UT"
+ revision = "b6e20af1ed078cd01a6413b734051a292450b4cb"
+ version = "v2.1.0"
+
[solve-meta]
analyzer-name = "dep"
analyzer-version = 1
@@ -410,6 +437,7 @@
"github.com/vektah/gqlparser/ast",
"golang.org/x/crypto/ssh/terminal",
"golang.org/x/oauth2",
+ "gotest.tools/assert",
]
solver-name = "gps-cdcl"
solver-version = 1
@@ -78,6 +78,13 @@ func TestBugSerialisation(t *testing.T) {
bug2.packs[0].Operations[i].base().hash = bug1.packs[0].Operations[i].base().hash
}
+ // check hashes
+ for i := range bug1.packs[0].Operations {
+ if !bug2.packs[0].Operations[i].base().hash.IsValid() {
+ t.Fatal("invalid hash")
+ }
+ }
+
deep.CompareUnexportedFields = true
if diff := deep.Equal(bug1, bug2); diff != nil {
t.Fatal(diff)
@@ -7,10 +7,9 @@ import (
"github.com/MichaelMure/git-bug/util/text"
)
-// AddCommentOperation will add a new comment in the bug
-
-var _ Operation = AddCommentOperation{}
+var _ Operation = &AddCommentOperation{}
+// AddCommentOperation will add a new comment in the bug
type AddCommentOperation struct {
*OpBase
Message string `json:"message"`
@@ -18,15 +17,15 @@ type AddCommentOperation struct {
Files []git.Hash `json:"files"`
}
-func (op AddCommentOperation) base() *OpBase {
+func (op *AddCommentOperation) base() *OpBase {
return op.OpBase
}
-func (op AddCommentOperation) Hash() (git.Hash, error) {
+func (op *AddCommentOperation) Hash() (git.Hash, error) {
return hashOperation(op)
}
-func (op AddCommentOperation) Apply(snapshot *Snapshot) {
+func (op *AddCommentOperation) Apply(snapshot *Snapshot) {
comment := Comment{
Message: op.Message,
Author: op.Author,
@@ -35,13 +34,22 @@ func (op AddCommentOperation) Apply(snapshot *Snapshot) {
}
snapshot.Comments = append(snapshot.Comments, comment)
+
+ hash, err := op.Hash()
+ if err != nil {
+ // Should never error unless a programming error happened
+ // (covered in OpBase.Validate())
+ panic(err)
+ }
+
+ snapshot.Timeline = append(snapshot.Timeline, NewCommentTimelineItem(hash, comment))
}
-func (op AddCommentOperation) GetFiles() []git.Hash {
+func (op *AddCommentOperation) GetFiles() []git.Hash {
return op.Files
}
-func (op AddCommentOperation) Validate() error {
+func (op *AddCommentOperation) Validate() error {
if err := opBaseValidate(op, AddCommentOp); err != nil {
return err
}
@@ -57,8 +65,8 @@ func (op AddCommentOperation) Validate() error {
return nil
}
-func NewAddCommentOp(author Person, unixTime int64, message string, files []git.Hash) AddCommentOperation {
- return AddCommentOperation{
+func NewAddCommentOp(author Person, unixTime int64, message string, files []git.Hash) *AddCommentOperation {
+ return &AddCommentOperation{
OpBase: newOpBase(AddCommentOp, author, unixTime),
Message: message,
Files: files,
@@ -8,10 +8,9 @@ import (
"github.com/MichaelMure/git-bug/util/text"
)
-// CreateOperation define the initial creation of a bug
-
-var _ Operation = CreateOperation{}
+var _ Operation = &CreateOperation{}
+// CreateOperation define the initial creation of a bug
type CreateOperation struct {
*OpBase
Title string `json:"title"`
@@ -19,32 +18,44 @@ type CreateOperation struct {
Files []git.Hash `json:"files"`
}
-func (op CreateOperation) base() *OpBase {
+func (op *CreateOperation) base() *OpBase {
return op.OpBase
}
-func (op CreateOperation) Hash() (git.Hash, error) {
+func (op *CreateOperation) Hash() (git.Hash, error) {
return hashOperation(op)
}
-func (op CreateOperation) Apply(snapshot *Snapshot) {
+func (op *CreateOperation) Apply(snapshot *Snapshot) {
snapshot.Title = op.Title
- snapshot.Comments = []Comment{
- {
- Message: op.Message,
- Author: op.Author,
- UnixTime: op.UnixTime,
- },
+
+ comment := Comment{
+ Message: op.Message,
+ Author: op.Author,
+ UnixTime: op.UnixTime,
}
+
+ snapshot.Comments = []Comment{comment}
snapshot.Author = op.Author
snapshot.CreatedAt = op.Time()
+
+ hash, err := op.Hash()
+ if err != nil {
+ // Should never error unless a programming error happened
+ // (covered in OpBase.Validate())
+ panic(err)
+ }
+
+ snapshot.Timeline = []TimelineItem{
+ NewCreateTimelineItem(hash, comment),
+ }
}
-func (op CreateOperation) GetFiles() []git.Hash {
+func (op *CreateOperation) GetFiles() []git.Hash {
return op.Files
}
-func (op CreateOperation) Validate() error {
+func (op *CreateOperation) Validate() error {
if err := opBaseValidate(op, CreateOp); err != nil {
return err
}
@@ -68,8 +79,8 @@ func (op CreateOperation) Validate() error {
return nil
}
-func NewCreateOp(author Person, unixTime int64, title, message string, files []git.Hash) CreateOperation {
- return CreateOperation{
+func NewCreateOp(author Person, unixTime int64, title, message string, files []git.Hash) *CreateOperation {
+ return &CreateOperation{
OpBase: newOpBase(CreateOp, author, unixTime),
Title: title,
Message: message,
@@ -1,9 +1,10 @@
package bug
import (
- "reflect"
"testing"
"time"
+
+ "github.com/go-test/deep"
)
func TestCreate(t *testing.T) {
@@ -20,16 +21,27 @@ func TestCreate(t *testing.T) {
create.Apply(&snapshot)
+ hash, err := create.Hash()
+ if err != nil {
+ t.Fatal(err)
+ }
+
+ comment := Comment{Author: rene, Message: "message", UnixTime: create.UnixTime}
+
expected := Snapshot{
Title: "title",
Comments: []Comment{
- {Author: rene, Message: "message", UnixTime: create.UnixTime},
+ comment,
},
Author: rene,
CreatedAt: create.Time(),
+ Timeline: []TimelineItem{
+ NewCreateTimelineItem(hash, comment),
+ },
}
- if !reflect.DeepEqual(snapshot, expected) {
- t.Fatalf("%v different than %v", snapshot, expected)
+ deep.CompareUnexportedFields = true
+ if diff := deep.Equal(snapshot, expected); diff != nil {
+ t.Fatal(diff)
}
}
@@ -0,0 +1,123 @@
+package bug
+
+import (
+ "fmt"
+
+ "github.com/MichaelMure/git-bug/util/git"
+ "github.com/MichaelMure/git-bug/util/text"
+)
+
+var _ Operation = &EditCommentOperation{}
+
+// EditCommentOperation will change a comment in the bug
+type EditCommentOperation struct {
+ *OpBase
+ Target git.Hash `json:"target"`
+ Message string `json:"message"`
+ Files []git.Hash `json:"files"`
+}
+
+func (op *EditCommentOperation) base() *OpBase {
+ return op.OpBase
+}
+
+func (op *EditCommentOperation) Hash() (git.Hash, error) {
+ return hashOperation(op)
+}
+
+func (op *EditCommentOperation) Apply(snapshot *Snapshot) {
+ // Todo: currently any message can be edited, even by a different author
+ // crypto signature are needed.
+
+ var target TimelineItem
+ var commentIndex int
+
+ for i, item := range snapshot.Timeline {
+ h, err := item.Hash()
+
+ if err != nil {
+ // Should never happen, we control what goes into the timeline
+ panic(err)
+ }
+
+ if h == op.Target {
+ target = snapshot.Timeline[i]
+ break
+ }
+
+ // Track the index in the []Comment
+ switch item.(type) {
+ case *CreateTimelineItem, *CommentTimelineItem:
+ commentIndex++
+ }
+ }
+
+ if target == nil {
+ // Target not found, edit is a no-op
+ return
+ }
+
+ switch target.(type) {
+ case *CreateTimelineItem:
+ item := target.(*CreateTimelineItem)
+ newComment := item.LastState()
+ newComment.Message = op.Message
+ item.History = append(item.History, newComment)
+
+ case *CommentTimelineItem:
+ item := target.(*CommentTimelineItem)
+ newComment := item.LastState()
+ newComment.Message = op.Message
+ item.History = append(item.History, newComment)
+ }
+
+ snapshot.Comments[commentIndex].Message = op.Message
+ snapshot.Comments[commentIndex].Files = op.Files
+}
+
+func (op *EditCommentOperation) GetFiles() []git.Hash {
+ return op.Files
+}
+
+func (op *EditCommentOperation) Validate() error {
+ if err := opBaseValidate(op, EditCommentOp); err != nil {
+ return err
+ }
+
+ if !op.Target.IsValid() {
+ return fmt.Errorf("target hash is invalid")
+ }
+
+ if text.Empty(op.Message) {
+ return fmt.Errorf("message is empty")
+ }
+
+ if !text.Safe(op.Message) {
+ return fmt.Errorf("message is not fully printable")
+ }
+
+ return nil
+}
+
+func NewEditCommentOp(author Person, unixTime int64, target git.Hash, message string, files []git.Hash) *EditCommentOperation {
+ return &EditCommentOperation{
+ OpBase: newOpBase(EditCommentOp, author, unixTime),
+ Target: target,
+ Message: message,
+ Files: files,
+ }
+}
+
+// Convenience function to apply the operation
+func EditComment(b Interface, author Person, unixTime int64, target git.Hash, message string) error {
+ return EditCommentWithFiles(b, author, unixTime, target, message, nil)
+}
+
+func EditCommentWithFiles(b Interface, author Person, unixTime int64, target git.Hash, message string, files []git.Hash) error {
+ editCommentOp := NewEditCommentOp(author, unixTime, target, message, files)
+ if err := editCommentOp.Validate(); err != nil {
+ return err
+ }
+ b.Append(editCommentOp)
+ return nil
+}
@@ -0,0 +1,53 @@
+package bug
+
+import (
+ "testing"
+ "time"
+
+ "gotest.tools/assert"
+)
+
+func TestEdit(t *testing.T) {
+ snapshot := Snapshot{}
+
+ var rene = Person{
+ Name: "RenΓ© Descartes",
+ Email: "rene@descartes.fr",
+ }
+
+ unix := time.Now().Unix()
+
+ create := NewCreateOp(rene, unix, "title", "create", nil)
+ create.Apply(&snapshot)
+
+ hash1, err := create.Hash()
+ if err != nil {
+ t.Fatal(err)
+ }
+
+ comment := NewAddCommentOp(rene, unix, "comment", nil)
+ comment.Apply(&snapshot)
+
+ hash2, err := comment.Hash()
+ if err != nil {
+ t.Fatal(err)
+ }
+
+ edit := NewEditCommentOp(rene, unix, hash1, "create edited", nil)
+ edit.Apply(&snapshot)
+
+ assert.Equal(t, len(snapshot.Timeline), 2)
+ assert.Equal(t, len(snapshot.Timeline[0].(*CreateTimelineItem).History), 2)
+ assert.Equal(t, len(snapshot.Timeline[1].(*CommentTimelineItem).History), 1)
+ assert.Equal(t, snapshot.Comments[0].Message, "create edited")
+ assert.Equal(t, snapshot.Comments[1].Message, "comment")
+
+ edit2 := NewEditCommentOp(rene, unix, hash2, "comment edited", nil)
+ edit2.Apply(&snapshot)
+
+ assert.Equal(t, len(snapshot.Timeline), 2)
+ assert.Equal(t, len(snapshot.Timeline[0].(*CreateTimelineItem).History), 2)
+ assert.Equal(t, len(snapshot.Timeline[1].(*CommentTimelineItem).History), 2)
+ assert.Equal(t, snapshot.Comments[0].Message, "create edited")
+ assert.Equal(t, snapshot.Comments[1].Message, "comment edited")
+}
@@ -8,7 +8,7 @@ import (
"github.com/pkg/errors"
)
-var _ Operation = LabelChangeOperation{}
+var _ Operation = &LabelChangeOperation{}
// LabelChangeOperation define a Bug operation to add or remove labels
type LabelChangeOperation struct {
@@ -17,16 +17,16 @@ type LabelChangeOperation struct {
Removed []Label `json:"removed"`
}
-func (op LabelChangeOperation) base() *OpBase {
+func (op *LabelChangeOperation) base() *OpBase {
return op.OpBase
}
-func (op LabelChangeOperation) Hash() (git.Hash, error) {
+func (op *LabelChangeOperation) Hash() (git.Hash, error) {
return hashOperation(op)
}
// Apply apply the operation
-func (op LabelChangeOperation) Apply(snapshot *Snapshot) {
+func (op *LabelChangeOperation) Apply(snapshot *Snapshot) {
// Add in the set
AddLoop:
for _, added := range op.Added {
@@ -54,9 +54,11 @@ AddLoop:
sort.Slice(snapshot.Labels, func(i, j int) bool {
return string(snapshot.Labels[i]) < string(snapshot.Labels[j])
})
+
+ snapshot.Timeline = append(snapshot.Timeline, op)
}
-func (op LabelChangeOperation) Validate() error {
+func (op *LabelChangeOperation) Validate() error {
if err := opBaseValidate(op, LabelChangeOp); err != nil {
return err
}
@@ -80,8 +82,8 @@ func (op LabelChangeOperation) Validate() error {
return nil
}
-func NewLabelChangeOperation(author Person, unixTime int64, added, removed []Label) LabelChangeOperation {
- return LabelChangeOperation{
+func NewLabelChangeOperation(author Person, unixTime int64, added, removed []Label) *LabelChangeOperation {
+ return &LabelChangeOperation{
OpBase: newOpBase(LabelChangeOp, author, unixTime),
Added: added,
Removed: removed,
@@ -5,28 +5,28 @@ import (
"github.com/pkg/errors"
)
-// SetStatusOperation will change the status of a bug
-
-var _ Operation = SetStatusOperation{}
+var _ Operation = &SetStatusOperation{}
+// SetStatusOperation will change the status of a bug
type SetStatusOperation struct {
*OpBase
Status Status `json:"status"`
}
-func (op SetStatusOperation) base() *OpBase {
+func (op *SetStatusOperation) base() *OpBase {
return op.OpBase
}
-func (op SetStatusOperation) Hash() (git.Hash, error) {
+func (op *SetStatusOperation) Hash() (git.Hash, error) {
return hashOperation(op)
}
-func (op SetStatusOperation) Apply(snapshot *Snapshot) {
+func (op *SetStatusOperation) Apply(snapshot *Snapshot) {
snapshot.Status = op.Status
+ snapshot.Timeline = append(snapshot.Timeline, op)
}
-func (op SetStatusOperation) Validate() error {
+func (op *SetStatusOperation) Validate() error {
if err := opBaseValidate(op, SetStatusOp); err != nil {
return err
}
@@ -38,8 +38,8 @@ func (op SetStatusOperation) Validate() error {
return nil
}
-func NewSetStatusOp(author Person, unixTime int64, status Status) SetStatusOperation {
- return SetStatusOperation{
+func NewSetStatusOp(author Person, unixTime int64, status Status) *SetStatusOperation {
+ return &SetStatusOperation{
OpBase: newOpBase(SetStatusOp, author, unixTime),
Status: status,
}
@@ -8,29 +8,29 @@ import (
"github.com/MichaelMure/git-bug/util/text"
)
-// SetTitleOperation will change the title of a bug
-
-var _ Operation = SetTitleOperation{}
+var _ Operation = &SetTitleOperation{}
+// SetTitleOperation will change the title of a bug
type SetTitleOperation struct {
*OpBase
Title string `json:"title"`
Was string `json:"was"`
}
-func (op SetTitleOperation) base() *OpBase {
+func (op *SetTitleOperation) base() *OpBase {
return op.OpBase
}
-func (op SetTitleOperation) Hash() (git.Hash, error) {
+func (op *SetTitleOperation) Hash() (git.Hash, error) {
return hashOperation(op)
}
-func (op SetTitleOperation) Apply(snapshot *Snapshot) {
+func (op *SetTitleOperation) Apply(snapshot *Snapshot) {
snapshot.Title = op.Title
+ snapshot.Timeline = append(snapshot.Timeline, op)
}
-func (op SetTitleOperation) Validate() error {
+func (op *SetTitleOperation) Validate() error {
if err := opBaseValidate(op, SetTitleOp); err != nil {
return err
}
@@ -58,8 +58,8 @@ func (op SetTitleOperation) Validate() error {
return nil
}
-func NewSetTitleOp(author Person, unixTime int64, title string, was string) SetTitleOperation {
- return SetTitleOperation{
+func NewSetTitleOp(author Person, unixTime int64, title string, was string) *SetTitleOperation {
+ return &SetTitleOperation{
OpBase: newOpBase(SetTitleOp, author, unixTime),
Title: title,
Was: was,
@@ -80,9 +80,9 @@ func SetTitle(b Interface, author Person, unixTime int64, title string) error {
var was string
if lastTitleOp != nil {
- was = lastTitleOp.(SetTitleOperation).Title
+ was = lastTitleOp.(*SetTitleOperation).Title
} else {
- was = b.FirstOp().(CreateOperation).Title
+ was = b.FirstOp().(*CreateOperation).Title
}
setTitleOp := NewSetTitleOp(author, unixTime, title, was)
@@ -20,13 +20,14 @@ const (
AddCommentOp
SetStatusOp
LabelChangeOp
+ EditCommentOp
)
// Operation define the interface to fulfill for an edit operation of a Bug
type Operation interface {
// base return the OpBase of the Operation, for package internal use
base() *OpBase
- // Hash return the hash of the operation
+ // Hash return the hash of the operation, to be used for back references
Hash() (git.Hash, error)
// Time return the time when the operation was added
Time() time.Time
@@ -46,7 +47,8 @@ type Operation interface {
func hashRaw(data []byte) git.Hash {
hasher := sha256.New()
- return git.Hash(fmt.Sprintf("%x", hasher.Sum(data)))
+ hasher.Write(data)
+ return git.Hash(fmt.Sprintf("%x", hasher.Sum(nil)))
}
// hash compute the hash of the serialized operation
@@ -106,6 +108,10 @@ func opBaseValidate(op Operation, opType OperationType) error {
return fmt.Errorf("incorrect operation type (expected: %v, actual: %v)", opType, op.base().OperationType)
}
+ if _, err := op.Hash(); err != nil {
+ return errors.Wrap(err, "op is not serializable")
+ }
+
if op.GetUnixTime() == 0 {
return fmt.Errorf("time not set")
}
@@ -74,23 +74,27 @@ func (opp *OperationPack) UnmarshalJSON(data []byte) error {
func (opp *OperationPack) unmarshalOp(raw []byte, _type OperationType) (Operation, error) {
switch _type {
case CreateOp:
- op := CreateOperation{}
+ op := &CreateOperation{}
err := json.Unmarshal(raw, &op)
return op, err
case SetTitleOp:
- op := SetTitleOperation{}
+ op := &SetTitleOperation{}
err := json.Unmarshal(raw, &op)
return op, err
case AddCommentOp:
- op := AddCommentOperation{}
+ op := &AddCommentOperation{}
err := json.Unmarshal(raw, &op)
return op, err
case SetStatusOp:
- op := SetStatusOperation{}
+ op := &SetStatusOperation{}
err := json.Unmarshal(raw, &op)
return op, err
case LabelChangeOp:
- op := LabelChangeOperation{}
+ op := &LabelChangeOperation{}
+ err := json.Unmarshal(raw, &op)
+ return op, err
+ case EditCommentOp:
+ op := &EditCommentOperation{}
err := json.Unmarshal(raw, &op)
return op, err
default:
@@ -36,7 +36,7 @@ func TestValidate(t *testing.T) {
NewSetStatusOp(Person{Name: "RenΓ© Descartes", Email: "rene@descartes.fr\u001b"}, unix, ClosedStatus),
NewSetStatusOp(Person{Name: "RenΓ© \nDescartes", Email: "rene@descartes.fr"}, unix, ClosedStatus),
NewSetStatusOp(Person{Name: "RenΓ© Descartes", Email: "rene@\ndescartes.fr"}, unix, ClosedStatus),
- CreateOperation{OpBase: &OpBase{
+ &CreateOperation{OpBase: &OpBase{
Author: rene,
UnixTime: 0,
OperationType: CreateOp,
@@ -3,6 +3,8 @@ package bug
import (
"fmt"
"time"
+
+ "github.com/MichaelMure/git-bug/util/git"
)
// Snapshot is a compiled form of the Bug data structure used for storage and merge
@@ -16,20 +18,22 @@ type Snapshot struct {
Author Person
CreatedAt time.Time
+ Timeline []TimelineItem
+
Operations []Operation
}
// Return the Bug identifier
-func (snap Snapshot) Id() string {
+func (snap *Snapshot) Id() string {
return snap.id
}
// Return the Bug identifier truncated for human consumption
-func (snap Snapshot) HumanId() string {
+func (snap *Snapshot) HumanId() string {
return fmt.Sprintf("%.8s", snap.id)
}
-func (snap Snapshot) Summary() string {
+func (snap *Snapshot) Summary() string {
return fmt.Sprintf("C:%d L:%d",
len(snap.Comments)-1,
len(snap.Labels),
@@ -37,7 +41,7 @@ func (snap Snapshot) Summary() string {
}
// Return the last time a bug was modified
-func (snap Snapshot) LastEditTime() time.Time {
+func (snap *Snapshot) LastEditTime() time.Time {
if len(snap.Operations) == 0 {
return time.Unix(0, 0)
}
@@ -46,10 +50,26 @@ func (snap Snapshot) LastEditTime() time.Time {
}
// Return the last timestamp a bug was modified
-func (snap Snapshot) LastEditUnix() int64 {
+func (snap *Snapshot) LastEditUnix() int64 {
if len(snap.Operations) == 0 {
return 0
}
return snap.Operations[len(snap.Operations)-1].GetUnixTime()
}
+
+// SearchTimelineItem will search in the timeline for an item matching the given hash
+func (snap *Snapshot) SearchTimelineItem(hash git.Hash) (TimelineItem, error) {
+ for i := range snap.Timeline {
+ h, err := snap.Timeline[i].Hash()
+ if err != nil {
+ return nil, err
+ }
+
+ if h == hash {
+ return snap.Timeline[i], nil
+ }
+ }
+
+ return nil, fmt.Errorf("timeline item not found")
+}
@@ -0,0 +1,62 @@
+package bug
+
+import "github.com/MichaelMure/git-bug/util/git"
+
+type TimelineItem interface {
+ // Hash return the hash of the item
+ Hash() (git.Hash, error)
+}
+
+// CreateTimelineItem replace a Create operation in the Timeline and hold its edition history
+type CreateTimelineItem struct {
+ hash git.Hash
+ History []Comment
+}
+
+func NewCreateTimelineItem(hash git.Hash, comment Comment) *CreateTimelineItem {
+ return &CreateTimelineItem{
+ hash: hash,
+ History: []Comment{
+ comment,
+ },
+ }
+}
+
+func (c *CreateTimelineItem) Hash() (git.Hash, error) {
+ return c.hash, nil
+}
+
+func (c *CreateTimelineItem) LastState() Comment {
+ if len(c.History) == 0 {
+ panic("no history yet")
+ }
+
+ return c.History[len(c.History)-1]
+}
+
+// CommentTimelineItem replace a Comment in the Timeline and hold its edition history
+type CommentTimelineItem struct {
+ hash git.Hash
+ History []Comment
+}
+
+func NewCommentTimelineItem(hash git.Hash, comment Comment) *CommentTimelineItem {
+ return &CommentTimelineItem{
+ hash: hash,
+ History: []Comment{
+ comment,
+ },
+ }
+}
+
+func (c *CommentTimelineItem) Hash() (git.Hash, error) {
+ return c.hash, nil
+}
+
+func (c *CommentTimelineItem) LastState() Comment {
+ if len(c.History) == 0 {
+ panic("no history yet")
+ }
+
+ return c.History[len(c.History)-1]
+}
@@ -0,0 +1,27 @@
+Copyright (c) 2017 The Go Authors. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+ * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+ * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+ * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
@@ -0,0 +1,553 @@
+// Copyright 2017, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE.md file.
+
+// Package cmp determines equality of values.
+//
+// This package is intended to be a more powerful and safer alternative to
+// reflect.DeepEqual for comparing whether two values are semantically equal.
+//
+// The primary features of cmp are:
+//
+// β’ When the default behavior of equality does not suit the needs of the test,
+// custom equality functions can override the equality operation.
+// For example, an equality function may report floats as equal so long as they
+// are within some tolerance of each other.
+//
+// β’ Types that have an Equal method may use that method to determine equality.
+// This allows package authors to determine the equality operation for the types
+// that they define.
+//
+// β’ If no custom equality functions are used and no Equal method is defined,
+// equality is determined by recursively comparing the primitive kinds on both
+// values, much like reflect.DeepEqual. Unlike reflect.DeepEqual, unexported
+// fields are not compared by default; they result in panics unless suppressed
+// by using an Ignore option (see cmpopts.IgnoreUnexported) or explicitly compared
+// using the AllowUnexported option.
+package cmp
+
+import (
+ "fmt"
+ "reflect"
+
+ "github.com/google/go-cmp/cmp/internal/diff"
+ "github.com/google/go-cmp/cmp/internal/function"
+ "github.com/google/go-cmp/cmp/internal/value"
+)
+
+// BUG(dsnet): Maps with keys containing NaN values cannot be properly compared due to
+// the reflection package's inability to retrieve such entries. Equal will panic
+// anytime it comes across a NaN key, but this behavior may change.
+//
+// See https://golang.org/issue/11104 for more details.
+
+var nothing = reflect.Value{}
+
+// Equal reports whether x and y are equal by recursively applying the
+// following rules in the given order to x and y and all of their sub-values:
+//
+// β’ If two values are not of the same type, then they are never equal
+// and the overall result is false.
+//
+// β’ Let S be the set of all Ignore, Transformer, and Comparer options that
+// remain after applying all path filters, value filters, and type filters.
+// If at least one Ignore exists in S, then the comparison is ignored.
+// If the number of Transformer and Comparer options in S is greater than one,
+// then Equal panics because it is ambiguous which option to use.
+// If S contains a single Transformer, then use that to transform the current
+// values and recursively call Equal on the output values.
+// If S contains a single Comparer, then use that to compare the current values.
+// Otherwise, evaluation proceeds to the next rule.
+//
+// β’ If the values have an Equal method of the form "(T) Equal(T) bool" or
+// "(T) Equal(I) bool" where T is assignable to I, then use the result of
+// x.Equal(y) even if x or y is nil.
+// Otherwise, no such method exists and evaluation proceeds to the next rule.
+//
+// β’ Lastly, try to compare x and y based on their basic kinds.
+// Simple kinds like booleans, integers, floats, complex numbers, strings, and
+// channels are compared using the equivalent of the == operator in Go.
+// Functions are only equal if they are both nil, otherwise they are unequal.
+// Pointers are equal if the underlying values they point to are also equal.
+// Interfaces are equal if their underlying concrete values are also equal.
+//
+// Structs are equal if all of their fields are equal. If a struct contains
+// unexported fields, Equal panics unless the AllowUnexported option is used or
+// an Ignore option (e.g., cmpopts.IgnoreUnexported) ignores that field.
+//
+// Arrays, slices, and maps are equal if they are both nil or both non-nil
+// with the same length and the elements at each index or key are equal.
+// Note that a non-nil empty slice and a nil slice are not equal.
+// To equate empty slices and maps, consider using cmpopts.EquateEmpty.
+// Map keys are equal according to the == operator.
+// To use custom comparisons for map keys, consider using cmpopts.SortMaps.
+func Equal(x, y interface{}, opts ...Option) bool {
+ s := newState(opts)
+ s.compareAny(reflect.ValueOf(x), reflect.ValueOf(y))
+ return s.result.Equal()
+}
+
+// Diff returns a human-readable report of the differences between two values.
+// It returns an empty string if and only if Equal returns true for the same
+// input values and options. The output string will use the "-" symbol to
+// indicate elements removed from x, and the "+" symbol to indicate elements
+// added to y.
+//
+// Do not depend on this output being stable.
+func Diff(x, y interface{}, opts ...Option) string {
+ r := new(defaultReporter)
+ opts = Options{Options(opts), r}
+ eq := Equal(x, y, opts...)
+ d := r.String()
+ if (d == "") != eq {
+ panic("inconsistent difference and equality results")
+ }
+ return d
+}
+
+type state struct {
+ // These fields represent the "comparison state".
+ // Calling statelessCompare must not result in observable changes to these.
+ result diff.Result // The current result of comparison
+ curPath Path // The current path in the value tree
+ reporter reporter // Optional reporter used for difference formatting
+
+ // dynChecker triggers pseudo-random checks for option correctness.
+ // It is safe for statelessCompare to mutate this value.
+ dynChecker dynChecker
+
+ // These fields, once set by processOption, will not change.
+ exporters map[reflect.Type]bool // Set of structs with unexported field visibility
+ opts Options // List of all fundamental and filter options
+}
+
+func newState(opts []Option) *state {
+ s := new(state)
+ for _, opt := range opts {
+ s.processOption(opt)
+ }
+ return s
+}
+
+func (s *state) processOption(opt Option) {
+ switch opt := opt.(type) {
+ case nil:
+ case Options:
+ for _, o := range opt {
+ s.processOption(o)
+ }
+ case coreOption:
+ type filtered interface {
+ isFiltered() bool
+ }
+ if fopt, ok := opt.(filtered); ok && !fopt.isFiltered() {
+ panic(fmt.Sprintf("cannot use an unfiltered option: %v", opt))
+ }
+ s.opts = append(s.opts, opt)
+ case visibleStructs:
+ if s.exporters == nil {
+ s.exporters = make(map[reflect.Type]bool)
+ }
+ for t := range opt {
+ s.exporters[t] = true
+ }
+ case reporter:
+ if s.reporter != nil {
+ panic("difference reporter already registered")
+ }
+ s.reporter = opt
+ default:
+ panic(fmt.Sprintf("unknown option %T", opt))
+ }
+}
+
+// statelessCompare compares two values and returns the result.
+// This function is stateless in that it does not alter the current result,
+// or output to any registered reporters.
+func (s *state) statelessCompare(vx, vy reflect.Value) diff.Result {
+ // We do not save and restore the curPath because all of the compareX
+ // methods should properly push and pop from the path.
+ // It is an implementation bug if the contents of curPath differs from
+ // when calling this function to when returning from it.
+
+ oldResult, oldReporter := s.result, s.reporter
+ s.result = diff.Result{} // Reset result
+ s.reporter = nil // Remove reporter to avoid spurious printouts
+ s.compareAny(vx, vy)
+ res := s.result
+ s.result, s.reporter = oldResult, oldReporter
+ return res
+}
+
+func (s *state) compareAny(vx, vy reflect.Value) {
+ // TODO: Support cyclic data structures.
+
+ // Rule 0: Differing types are never equal.
+ if !vx.IsValid() || !vy.IsValid() {
+ s.report(vx.IsValid() == vy.IsValid(), vx, vy)
+ return
+ }
+ if vx.Type() != vy.Type() {
+ s.report(false, vx, vy) // Possible for path to be empty
+ return
+ }
+ t := vx.Type()
+ if len(s.curPath) == 0 {
+ s.curPath.push(&pathStep{typ: t})
+ defer s.curPath.pop()
+ }
+ vx, vy = s.tryExporting(vx, vy)
+
+ // Rule 1: Check whether an option applies on this node in the value tree.
+ if s.tryOptions(vx, vy, t) {
+ return
+ }
+
+ // Rule 2: Check whether the type has a valid Equal method.
+ if s.tryMethod(vx, vy, t) {
+ return
+ }
+
+ // Rule 3: Recursively descend into each value's underlying kind.
+ switch t.Kind() {
+ case reflect.Bool:
+ s.report(vx.Bool() == vy.Bool(), vx, vy)
+ return
+ case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+ s.report(vx.Int() == vy.Int(), vx, vy)
+ return
+ case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+ s.report(vx.Uint() == vy.Uint(), vx, vy)
+ return
+ case reflect.Float32, reflect.Float64:
+ s.report(vx.Float() == vy.Float(), vx, vy)
+ return
+ case reflect.Complex64, reflect.Complex128:
+ s.report(vx.Complex() == vy.Complex(), vx, vy)
+ return
+ case reflect.String:
+ s.report(vx.String() == vy.String(), vx, vy)
+ return
+ case reflect.Chan, reflect.UnsafePointer:
+ s.report(vx.Pointer() == vy.Pointer(), vx, vy)
+ return
+ case reflect.Func:
+ s.report(vx.IsNil() && vy.IsNil(), vx, vy)
+ return
+ case reflect.Ptr:
+ if vx.IsNil() || vy.IsNil() {
+ s.report(vx.IsNil() && vy.IsNil(), vx, vy)
+ return
+ }
+ s.curPath.push(&indirect{pathStep{t.Elem()}})
+ defer s.curPath.pop()
+ s.compareAny(vx.Elem(), vy.Elem())
+ return
+ case reflect.Interface:
+ if vx.IsNil() || vy.IsNil() {
+ s.report(vx.IsNil() && vy.IsNil(), vx, vy)
+ return
+ }
+ if vx.Elem().Type() != vy.Elem().Type() {
+ s.report(false, vx.Elem(), vy.Elem())
+ return
+ }
+ s.curPath.push(&typeAssertion{pathStep{vx.Elem().Type()}})
+ defer s.curPath.pop()
+ s.compareAny(vx.Elem(), vy.Elem())
+ return
+ case reflect.Slice:
+ if vx.IsNil() || vy.IsNil() {
+ s.report(vx.IsNil() && vy.IsNil(), vx, vy)
+ return
+ }
+ fallthrough
+ case reflect.Array:
+ s.compareArray(vx, vy, t)
+ return
+ case reflect.Map:
+ s.compareMap(vx, vy, t)
+ return
+ case reflect.Struct:
+ s.compareStruct(vx, vy, t)
+ return
+ default:
+ panic(fmt.Sprintf("%v kind not handled", t.Kind()))
+ }
+}
+
+func (s *state) tryExporting(vx, vy reflect.Value) (reflect.Value, reflect.Value) {
+ if sf, ok := s.curPath[len(s.curPath)-1].(*structField); ok && sf.unexported {
+ if sf.force {
+ // Use unsafe pointer arithmetic to get read-write access to an
+ // unexported field in the struct.
+ vx = unsafeRetrieveField(sf.pvx, sf.field)
+ vy = unsafeRetrieveField(sf.pvy, sf.field)
+ } else {
+ // We are not allowed to export the value, so invalidate them
+ // so that tryOptions can panic later if not explicitly ignored.
+ vx = nothing
+ vy = nothing
+ }
+ }
+ return vx, vy
+}
+
+func (s *state) tryOptions(vx, vy reflect.Value, t reflect.Type) bool {
+ // If there were no FilterValues, we will not detect invalid inputs,
+ // so manually check for them and append invalid if necessary.
+ // We still evaluate the options since an ignore can override invalid.
+ opts := s.opts
+ if !vx.IsValid() || !vy.IsValid() {
+ opts = Options{opts, invalid{}}
+ }
+
+ // Evaluate all filters and apply the remaining options.
+ if opt := opts.filter(s, vx, vy, t); opt != nil {
+ opt.apply(s, vx, vy)
+ return true
+ }
+ return false
+}
+
+func (s *state) tryMethod(vx, vy reflect.Value, t reflect.Type) bool {
+ // Check if this type even has an Equal method.
+ m, ok := t.MethodByName("Equal")
+ if !ok || !function.IsType(m.Type, function.EqualAssignable) {
+ return false
+ }
+
+ eq := s.callTTBFunc(m.Func, vx, vy)
+ s.report(eq, vx, vy)
+ return true
+}
+
+func (s *state) callTRFunc(f, v reflect.Value) reflect.Value {
+ v = sanitizeValue(v, f.Type().In(0))
+ if !s.dynChecker.Next() {
+ return f.Call([]reflect.Value{v})[0]
+ }
+
+ // Run the function twice and ensure that we get the same results back.
+ // We run in goroutines so that the race detector (if enabled) can detect
+ // unsafe mutations to the input.
+ c := make(chan reflect.Value)
+ go detectRaces(c, f, v)
+ want := f.Call([]reflect.Value{v})[0]
+ if got := <-c; !s.statelessCompare(got, want).Equal() {
+ // To avoid false-positives with non-reflexive equality operations,
+ // we sanity check whether a value is equal to itself.
+ if !s.statelessCompare(want, want).Equal() {
+ return want
+ }
+ fn := getFuncName(f.Pointer())
+ panic(fmt.Sprintf("non-deterministic function detected: %s", fn))
+ }
+ return want
+}
+
+func (s *state) callTTBFunc(f, x, y reflect.Value) bool {
+ x = sanitizeValue(x, f.Type().In(0))
+ y = sanitizeValue(y, f.Type().In(1))
+ if !s.dynChecker.Next() {
+ return f.Call([]reflect.Value{x, y})[0].Bool()
+ }
+
+ // Swapping the input arguments is sufficient to check that
+ // f is symmetric and deterministic.
+ // We run in goroutines so that the race detector (if enabled) can detect
+ // unsafe mutations to the input.
+ c := make(chan reflect.Value)
+ go detectRaces(c, f, y, x)
+ want := f.Call([]reflect.Value{x, y})[0].Bool()
+ if got := <-c; !got.IsValid() || got.Bool() != want {
+ fn := getFuncName(f.Pointer())
+ panic(fmt.Sprintf("non-deterministic or non-symmetric function detected: %s", fn))
+ }
+ return want
+}
+
+func detectRaces(c chan<- reflect.Value, f reflect.Value, vs ...reflect.Value) {
+ var ret reflect.Value
+ defer func() {
+ recover() // Ignore panics, let the other call to f panic instead
+ c <- ret
+ }()
+ ret = f.Call(vs)[0]
+}
+
+// sanitizeValue converts nil interfaces of type T to those of type R,
+// assuming that T is assignable to R.
+// Otherwise, it returns the input value as is.
+func sanitizeValue(v reflect.Value, t reflect.Type) reflect.Value {
+ // TODO(dsnet): Remove this hacky workaround.
+ // See https://golang.org/issue/22143
+ if v.Kind() == reflect.Interface && v.IsNil() && v.Type() != t {
+ return reflect.New(t).Elem()
+ }
+ return v
+}
+
+func (s *state) compareArray(vx, vy reflect.Value, t reflect.Type) {
+ step := &sliceIndex{pathStep{t.Elem()}, 0, 0}
+ s.curPath.push(step)
+
+ // Compute an edit-script for slices vx and vy.
+ es := diff.Difference(vx.Len(), vy.Len(), func(ix, iy int) diff.Result {
+ step.xkey, step.ykey = ix, iy
+ return s.statelessCompare(vx.Index(ix), vy.Index(iy))
+ })
+
+ // Report the entire slice as is if the arrays are of primitive kind,
+ // and the arrays are different enough.
+ isPrimitive := false
+ switch t.Elem().Kind() {
+ case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64,
+ reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr,
+ reflect.Bool, reflect.Float32, reflect.Float64, reflect.Complex64, reflect.Complex128:
+ isPrimitive = true
+ }
+ if isPrimitive && es.Dist() > (vx.Len()+vy.Len())/4 {
+ s.curPath.pop() // Pop first since we are reporting the whole slice
+ s.report(false, vx, vy)
+ return
+ }
+
+ // Replay the edit-script.
+ var ix, iy int
+ for _, e := range es {
+ switch e {
+ case diff.UniqueX:
+ step.xkey, step.ykey = ix, -1
+ s.report(false, vx.Index(ix), nothing)
+ ix++
+ case diff.UniqueY:
+ step.xkey, step.ykey = -1, iy
+ s.report(false, nothing, vy.Index(iy))
+ iy++
+ default:
+ step.xkey, step.ykey = ix, iy
+ if e == diff.Identity {
+ s.report(true, vx.Index(ix), vy.Index(iy))
+ } else {
+ s.compareAny(vx.Index(ix), vy.Index(iy))
+ }
+ ix++
+ iy++
+ }
+ }
+ s.curPath.pop()
+ return
+}
+
+func (s *state) compareMap(vx, vy reflect.Value, t reflect.Type) {
+ if vx.IsNil() || vy.IsNil() {
+ s.report(vx.IsNil() && vy.IsNil(), vx, vy)
+ return
+ }
+
+ // We combine and sort the two map keys so that we can perform the
+ // comparisons in a deterministic order.
+ step := &mapIndex{pathStep: pathStep{t.Elem()}}
+ s.curPath.push(step)
+ defer s.curPath.pop()
+ for _, k := range value.SortKeys(append(vx.MapKeys(), vy.MapKeys()...)) {
+ step.key = k
+ vvx := vx.MapIndex(k)
+ vvy := vy.MapIndex(k)
+ switch {
+ case vvx.IsValid() && vvy.IsValid():
+ s.compareAny(vvx, vvy)
+ case vvx.IsValid() && !vvy.IsValid():
+ s.report(false, vvx, nothing)
+ case !vvx.IsValid() && vvy.IsValid():
+ s.report(false, nothing, vvy)
+ default:
+ // It is possible for both vvx and vvy to be invalid if the
+ // key contained a NaN value in it. There is no way in
+ // reflection to be able to retrieve these values.
+ // See https://golang.org/issue/11104
+ panic(fmt.Sprintf("%#v has map key with NaNs", s.curPath))
+ }
+ }
+}
+
+func (s *state) compareStruct(vx, vy reflect.Value, t reflect.Type) {
+ var vax, vay reflect.Value // Addressable versions of vx and vy
+
+ step := &structField{}
+ s.curPath.push(step)
+ defer s.curPath.pop()
+ for i := 0; i < t.NumField(); i++ {
+ vvx := vx.Field(i)
+ vvy := vy.Field(i)
+ step.typ = t.Field(i).Type
+ step.name = t.Field(i).Name
+ step.idx = i
+ step.unexported = !isExported(step.name)
+ if step.unexported {
+ // Defer checking of unexported fields until later to give an
+ // Ignore a chance to ignore the field.
+ if !vax.IsValid() || !vay.IsValid() {
+ // For unsafeRetrieveField to work, the parent struct must
+ // be addressable. Create a new copy of the values if
+ // necessary to make them addressable.
+ vax = makeAddressable(vx)
+ vay = makeAddressable(vy)
+ }
+ step.force = s.exporters[t]
+ step.pvx = vax
+ step.pvy = vay
+ step.field = t.Field(i)
+ }
+ s.compareAny(vvx, vvy)
+ }
+}
+
+// report records the result of a single comparison.
+// It also calls Report if any reporter is registered.
+func (s *state) report(eq bool, vx, vy reflect.Value) {
+ if eq {
+ s.result.NSame++
+ } else {
+ s.result.NDiff++
+ }
+ if s.reporter != nil {
+ s.reporter.Report(vx, vy, eq, s.curPath)
+ }
+}
+
+// dynChecker tracks the state needed to periodically perform checks that
+// user provided functions are symmetric and deterministic.
+// The zero value is safe for immediate use.
+type dynChecker struct{ curr, next int }
+
+// Next increments the state and reports whether a check should be performed.
+//
+// Checks occur every Nth function call, where N is a triangular number:
+// 0 1 3 6 10 15 21 28 36 45 55 66 78 91 105 120 136 153 171 190 ...
+// See https://en.wikipedia.org/wiki/Triangular_number
+//
+// This sequence ensures that the cost of checks drops significantly as
+// the number of functions calls grows larger.
+func (dc *dynChecker) Next() bool {
+ ok := dc.curr == dc.next
+ if ok {
+ dc.curr = 0
+ dc.next++
+ }
+ dc.curr++
+ return ok
+}
+
+// makeAddressable returns a value that is always addressable.
+// It returns the input verbatim if it is already addressable,
+// otherwise it creates a new value and returns an addressable copy.
+func makeAddressable(v reflect.Value) reflect.Value {
+ if v.CanAddr() {
+ return v
+ }
+ vc := reflect.New(v.Type()).Elem()
+ vc.Set(v)
+ return vc
+}
@@ -0,0 +1,17 @@
+// Copyright 2017, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE.md file.
+
+// +build !debug
+
+package diff
+
+var debug debugger
+
+type debugger struct{}
+
+func (debugger) Begin(_, _ int, f EqualFunc, _, _ *EditScript) EqualFunc {
+ return f
+}
+func (debugger) Update() {}
+func (debugger) Finish() {}
@@ -0,0 +1,122 @@
+// Copyright 2017, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE.md file.
+
+// +build debug
+
+package diff
+
+import (
+ "fmt"
+ "strings"
+ "sync"
+ "time"
+)
+
+// The algorithm can be seen running in real-time by enabling debugging:
+// go test -tags=debug -v
+//
+// Example output:
+// === RUN TestDifference/#34
+// βββββββββββββββββββββββββββββββββ
+// β \ Β· Β· Β· Β· Β· Β· Β· Β· Β· Β· Β· Β· Β· Β· β
+// β Β· # Β· Β· Β· Β· Β· Β· Β· Β· Β· Β· Β· Β· Β· β
+// β Β· \ Β· Β· Β· Β· Β· Β· Β· Β· Β· Β· Β· Β· Β· β
+// β Β· Β· \ Β· Β· Β· Β· Β· Β· Β· Β· Β· Β· Β· Β· β
+// β Β· Β· Β· X # Β· Β· Β· Β· Β· Β· Β· Β· Β· Β· β
+// β Β· Β· Β· # \ Β· Β· Β· Β· Β· Β· Β· Β· Β· Β· β
+// β Β· Β· Β· Β· Β· # # Β· Β· Β· Β· Β· Β· Β· Β· β
+// β Β· Β· Β· Β· Β· # \ Β· Β· Β· Β· Β· Β· Β· Β· β
+// β Β· Β· Β· Β· Β· Β· Β· \ Β· Β· Β· Β· Β· Β· Β· β
+// β Β· Β· Β· Β· Β· Β· Β· Β· \ Β· Β· Β· Β· Β· Β· β
+// β Β· Β· Β· Β· Β· Β· Β· Β· Β· \ Β· Β· Β· Β· Β· β
+// β Β· Β· Β· Β· Β· Β· Β· Β· Β· Β· \ Β· Β· # Β· β
+// β Β· Β· Β· Β· Β· Β· Β· Β· Β· Β· Β· \ # # Β· β
+// β Β· Β· Β· Β· Β· Β· Β· Β· Β· Β· Β· # # # Β· β
+// β Β· Β· Β· Β· Β· Β· Β· Β· Β· Β· # # # # Β· β
+// β Β· Β· Β· Β· Β· Β· Β· Β· Β· # # # # # Β· β
+// β Β· Β· Β· Β· Β· Β· Β· Β· Β· Β· Β· Β· Β· Β· \ β
+// βββββββββββββββββββββββββββββββββ
+// [.Y..M.XY......YXYXY.|]
+//
+// The grid represents the edit-graph where the horizontal axis represents
+// list X and the vertical axis represents list Y. The start of the two lists
+// is the top-left, while the ends are the bottom-right. The 'Β·' represents
+// an unexplored node in the graph. The '\' indicates that the two symbols
+// from list X and Y are equal. The 'X' indicates that two symbols are similar
+// (but not exactly equal) to each other. The '#' indicates that the two symbols
+// are different (and not similar). The algorithm traverses this graph trying to
+// make the paths starting in the top-left and the bottom-right connect.
+//
+// The series of '.', 'X', 'Y', and 'M' characters at the bottom represents
+// the currently established path from the forward and reverse searches,
+// separated by a '|' character.
+
+const (
+ updateDelay = 100 * time.Millisecond
+ finishDelay = 500 * time.Millisecond
+ ansiTerminal = true // ANSI escape codes used to move terminal cursor
+)
+
+var debug debugger
+
+type debugger struct {
+ sync.Mutex
+ p1, p2 EditScript
+ fwdPath, revPath *EditScript
+ grid []byte
+ lines int
+}
+
+func (dbg *debugger) Begin(nx, ny int, f EqualFunc, p1, p2 *EditScript) EqualFunc {
+ dbg.Lock()
+ dbg.fwdPath, dbg.revPath = p1, p2
+ top := "ββ" + strings.Repeat("ββ", nx) + "β\n"
+ row := "β " + strings.Repeat("Β· ", nx) + "β\n"
+ btm := "ββ" + strings.Repeat("ββ", nx) + "β\n"
+ dbg.grid = []byte(top + strings.Repeat(row, ny) + btm)
+ dbg.lines = strings.Count(dbg.String(), "\n")
+ fmt.Print(dbg)
+
+ // Wrap the EqualFunc so that we can intercept each result.
+ return func(ix, iy int) (r Result) {
+ cell := dbg.grid[len(top)+iy*len(row):][len("β ")+len("Β· ")*ix:][:len("Β·")]
+ for i := range cell {
+ cell[i] = 0 // Zero out the multiple bytes of UTF-8 middle-dot
+ }
+ switch r = f(ix, iy); {
+ case r.Equal():
+ cell[0] = '\\'
+ case r.Similar():
+ cell[0] = 'X'
+ default:
+ cell[0] = '#'
+ }
+ return
+ }
+}
+
+func (dbg *debugger) Update() {
+ dbg.print(updateDelay)
+}
+
+func (dbg *debugger) Finish() {
+ dbg.print(finishDelay)
+ dbg.Unlock()
+}
+
+func (dbg *debugger) String() string {
+ dbg.p1, dbg.p2 = *dbg.fwdPath, dbg.p2[:0]
+ for i := len(*dbg.revPath) - 1; i >= 0; i-- {
+ dbg.p2 = append(dbg.p2, (*dbg.revPath)[i])
+ }
+ return fmt.Sprintf("%s[%v|%v]\n\n", dbg.grid, dbg.p1, dbg.p2)
+}
+
+func (dbg *debugger) print(d time.Duration) {
+ if ansiTerminal {
+ fmt.Printf("\x1b[%dA", dbg.lines) // Reset terminal cursor
+ }
+ fmt.Print(dbg)
+ time.Sleep(d)
+}
@@ -0,0 +1,363 @@
+// Copyright 2017, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE.md file.
+
+// Package diff implements an algorithm for producing edit-scripts.
+// The edit-script is a sequence of operations needed to transform one list
+// of symbols into another (or vice-versa). The edits allowed are insertions,
+// deletions, and modifications. The summation of all edits is called the
+// Levenshtein distance as this problem is well-known in computer science.
+//
+// This package prioritizes performance over accuracy. That is, the run time
+// is more important than obtaining a minimal Levenshtein distance.
+package diff
+
+// EditType represents a single operation within an edit-script.
+type EditType uint8
+
+const (
+ // Identity indicates that a symbol pair is identical in both list X and Y.
+ Identity EditType = iota
+ // UniqueX indicates that a symbol only exists in X and not Y.
+ UniqueX
+ // UniqueY indicates that a symbol only exists in Y and not X.
+ UniqueY
+ // Modified indicates that a symbol pair is a modification of each other.
+ Modified
+)
+
+// EditScript represents the series of differences between two lists.
+type EditScript []EditType
+
+// String returns a human-readable string representing the edit-script where
+// Identity, UniqueX, UniqueY, and Modified are represented by the
+// '.', 'X', 'Y', and 'M' characters, respectively.
+func (es EditScript) String() string {
+ b := make([]byte, len(es))
+ for i, e := range es {
+ switch e {
+ case Identity:
+ b[i] = '.'
+ case UniqueX:
+ b[i] = 'X'
+ case UniqueY:
+ b[i] = 'Y'
+ case Modified:
+ b[i] = 'M'
+ default:
+ panic("invalid edit-type")
+ }
+ }
+ return string(b)
+}
+
+// stats returns a histogram of the number of each type of edit operation.
+func (es EditScript) stats() (s struct{ NI, NX, NY, NM int }) {
+ for _, e := range es {
+ switch e {
+ case Identity:
+ s.NI++
+ case UniqueX:
+ s.NX++
+ case UniqueY:
+ s.NY++
+ case Modified:
+ s.NM++
+ default:
+ panic("invalid edit-type")
+ }
+ }
+ return
+}
+
+// Dist is the Levenshtein distance and is guaranteed to be 0 if and only if
+// lists X and Y are equal.
+func (es EditScript) Dist() int { return len(es) - es.stats().NI }
+
+// LenX is the length of the X list.
+func (es EditScript) LenX() int { return len(es) - es.stats().NY }
+
+// LenY is the length of the Y list.
+func (es EditScript) LenY() int { return len(es) - es.stats().NX }
+
+// EqualFunc reports whether the symbols at indexes ix and iy are equal.
+// When called by Difference, the index is guaranteed to be within nx and ny.
+type EqualFunc func(ix int, iy int) Result
+
+// Result is the result of comparison.
+// NSame is the number of sub-elements that are equal.
+// NDiff is the number of sub-elements that are not equal.
+type Result struct{ NSame, NDiff int }
+
+// Equal indicates whether the symbols are equal. Two symbols are equal
+// if and only if NDiff == 0. If Equal, then they are also Similar.
+func (r Result) Equal() bool { return r.NDiff == 0 }
+
+// Similar indicates whether two symbols are similar and may be represented
+// by using the Modified type. As a special case, we consider binary comparisons
+// (i.e., those that return Result{1, 0} or Result{0, 1}) to be similar.
+//
+// The exact ratio of NSame to NDiff to determine similarity may change.
+func (r Result) Similar() bool {
+ // Use NSame+1 to offset NSame so that binary comparisons are similar.
+ return r.NSame+1 >= r.NDiff
+}
+
+// Difference reports whether two lists of lengths nx and ny are equal
+// given the definition of equality provided as f.
+//
+// This function returns an edit-script, which is a sequence of operations
+// needed to convert one list into the other. The following invariants for
+// the edit-script are maintained:
+// β’ eq == (es.Dist()==0)
+// β’ nx == es.LenX()
+// β’ ny == es.LenY()
+//
+// This algorithm is not guaranteed to be an optimal solution (i.e., one that
+// produces an edit-script with a minimal Levenshtein distance). This algorithm
+// favors performance over optimality. The exact output is not guaranteed to
+// be stable and may change over time.
+func Difference(nx, ny int, f EqualFunc) (es EditScript) {
+ // This algorithm is based on traversing what is known as an "edit-graph".
+ // See Figure 1 from "An O(ND) Difference Algorithm and Its Variations"
+ // by Eugene W. Myers. Since D can be as large as N itself, this is
+ // effectively O(N^2). Unlike the algorithm from that paper, we are not
+ // interested in the optimal path, but at least some "decent" path.
+ //
+ // For example, let X and Y be lists of symbols:
+ // X = [A B C A B B A]
+ // Y = [C B A B A C]
+ //
+ // The edit-graph can be drawn as the following:
+ // A B C A B B A
+ // βββββββββββββββ
+ // C β_|_|\|_|_|_|_β 0
+ // B β_|\|_|_|\|\|_β 1
+ // A β\|_|_|\|_|_|\β 2
+ // B β_|\|_|_|\|\|_β 3
+ // A β\|_|_|\|_|_|\β 4
+ // C β | |\| | | | β 5
+ // βββββββββββββββ 6
+ // 0 1 2 3 4 5 6 7
+ //
+ // List X is written along the horizontal axis, while list Y is written
+ // along the vertical axis. At any point on this grid, if the symbol in
+ // list X matches the corresponding symbol in list Y, then a '\' is drawn.
+ // The goal of any minimal edit-script algorithm is to find a path from the
+ // top-left corner to the bottom-right corner, while traveling through the
+ // fewest horizontal or vertical edges.
+ // A horizontal edge is equivalent to inserting a symbol from list X.
+ // A vertical edge is equivalent to inserting a symbol from list Y.
+ // A diagonal edge is equivalent to a matching symbol between both X and Y.
+
+ // Invariants:
+ // β’ 0 β€ fwdPath.X β€ (fwdFrontier.X, revFrontier.X) β€ revPath.X β€ nx
+ // β’ 0 β€ fwdPath.Y β€ (fwdFrontier.Y, revFrontier.Y) β€ revPath.Y β€ ny
+ //
+ // In general:
+ // β’ fwdFrontier.X < revFrontier.X
+ // β’ fwdFrontier.Y < revFrontier.Y
+ // Unless, it is time for the algorithm to terminate.
+ fwdPath := path{+1, point{0, 0}, make(EditScript, 0, (nx+ny)/2)}
+ revPath := path{-1, point{nx, ny}, make(EditScript, 0)}
+ fwdFrontier := fwdPath.point // Forward search frontier
+ revFrontier := revPath.point // Reverse search frontier
+
+ // Search budget bounds the cost of searching for better paths.
+ // The longest sequence of non-matching symbols that can be tolerated is
+ // approximately the square-root of the search budget.
+ searchBudget := 4 * (nx + ny) // O(n)
+
+ // The algorithm below is a greedy, meet-in-the-middle algorithm for
+ // computing sub-optimal edit-scripts between two lists.
+ //
+ // The algorithm is approximately as follows:
+ // β’ Searching for differences switches back-and-forth between
+ // a search that starts at the beginning (the top-left corner), and
+ // a search that starts at the end (the bottom-right corner). The goal of
+ // the search is connect with the search from the opposite corner.
+ // β’ As we search, we build a path in a greedy manner, where the first
+ // match seen is added to the path (this is sub-optimal, but provides a
+ // decent result in practice). When matches are found, we try the next pair
+ // of symbols in the lists and follow all matches as far as possible.
+ // β’ When searching for matches, we search along a diagonal going through
+ // through the "frontier" point. If no matches are found, we advance the
+ // frontier towards the opposite corner.
+ // β’ This algorithm terminates when either the X coordinates or the
+ // Y coordinates of the forward and reverse frontier points ever intersect.
+ //
+ // This algorithm is correct even if searching only in the forward direction
+ // or in the reverse direction. We do both because it is commonly observed
+ // that two lists commonly differ because elements were added to the front
+ // or end of the other list.
+ //
+ // Running the tests with the "debug" build tag prints a visualization of
+ // the algorithm running in real-time. This is educational for understanding
+ // how the algorithm works. See debug_enable.go.
+ f = debug.Begin(nx, ny, f, &fwdPath.es, &revPath.es)
+ for {
+ // Forward search from the beginning.
+ if fwdFrontier.X >= revFrontier.X || fwdFrontier.Y >= revFrontier.Y || searchBudget == 0 {
+ break
+ }
+ for stop1, stop2, i := false, false, 0; !(stop1 && stop2) && searchBudget > 0; i++ {
+ // Search in a diagonal pattern for a match.
+ z := zigzag(i)
+ p := point{fwdFrontier.X + z, fwdFrontier.Y - z}
+ switch {
+ case p.X >= revPath.X || p.Y < fwdPath.Y:
+ stop1 = true // Hit top-right corner
+ case p.Y >= revPath.Y || p.X < fwdPath.X:
+ stop2 = true // Hit bottom-left corner
+ case f(p.X, p.Y).Equal():
+ // Match found, so connect the path to this point.
+ fwdPath.connect(p, f)
+ fwdPath.append(Identity)
+ // Follow sequence of matches as far as possible.
+ for fwdPath.X < revPath.X && fwdPath.Y < revPath.Y {
+ if !f(fwdPath.X, fwdPath.Y).Equal() {
+ break
+ }
+ fwdPath.append(Identity)
+ }
+ fwdFrontier = fwdPath.point
+ stop1, stop2 = true, true
+ default:
+ searchBudget-- // Match not found
+ }
+ debug.Update()
+ }
+ // Advance the frontier towards reverse point.
+ if revPath.X-fwdFrontier.X >= revPath.Y-fwdFrontier.Y {
+ fwdFrontier.X++
+ } else {
+ fwdFrontier.Y++
+ }
+
+ // Reverse search from the end.
+ if fwdFrontier.X >= revFrontier.X || fwdFrontier.Y >= revFrontier.Y || searchBudget == 0 {
+ break
+ }
+ for stop1, stop2, i := false, false, 0; !(stop1 && stop2) && searchBudget > 0; i++ {
+ // Search in a diagonal pattern for a match.
+ z := zigzag(i)
+ p := point{revFrontier.X - z, revFrontier.Y + z}
+ switch {
+ case fwdPath.X >= p.X || revPath.Y < p.Y:
+ stop1 = true // Hit bottom-left corner
+ case fwdPath.Y >= p.Y || revPath.X < p.X:
+ stop2 = true // Hit top-right corner
+ case f(p.X-1, p.Y-1).Equal():
+ // Match found, so connect the path to this point.
+ revPath.connect(p, f)
+ revPath.append(Identity)
+ // Follow sequence of matches as far as possible.
+ for fwdPath.X < revPath.X && fwdPath.Y < revPath.Y {
+ if !f(revPath.X-1, revPath.Y-1).Equal() {
+ break
+ }
+ revPath.append(Identity)
+ }
+ revFrontier = revPath.point
+ stop1, stop2 = true, true
+ default:
+ searchBudget-- // Match not found
+ }
+ debug.Update()
+ }
+ // Advance the frontier towards forward point.
+ if revFrontier.X-fwdPath.X >= revFrontier.Y-fwdPath.Y {
+ revFrontier.X--
+ } else {
+ revFrontier.Y--
+ }
+ }
+
+ // Join the forward and reverse paths and then append the reverse path.
+ fwdPath.connect(revPath.point, f)
+ for i := len(revPath.es) - 1; i >= 0; i-- {
+ t := revPath.es[i]
+ revPath.es = revPath.es[:i]
+ fwdPath.append(t)
+ }
+ debug.Finish()
+ return fwdPath.es
+}
+
+type path struct {
+ dir int // +1 if forward, -1 if reverse
+ point // Leading point of the EditScript path
+ es EditScript
+}
+
+// connect appends any necessary Identity, Modified, UniqueX, or UniqueY types
+// to the edit-script to connect p.point to dst.
+func (p *path) connect(dst point, f EqualFunc) {
+ if p.dir > 0 {
+ // Connect in forward direction.
+ for dst.X > p.X && dst.Y > p.Y {
+ switch r := f(p.X, p.Y); {
+ case r.Equal():
+ p.append(Identity)
+ case r.Similar():
+ p.append(Modified)
+ case dst.X-p.X >= dst.Y-p.Y:
+ p.append(UniqueX)
+ default:
+ p.append(UniqueY)
+ }
+ }
+ for dst.X > p.X {
+ p.append(UniqueX)
+ }
+ for dst.Y > p.Y {
+ p.append(UniqueY)
+ }
+ } else {
+ // Connect in reverse direction.
+ for p.X > dst.X && p.Y > dst.Y {
+ switch r := f(p.X-1, p.Y-1); {
+ case r.Equal():
+ p.append(Identity)
+ case r.Similar():
+ p.append(Modified)
+ case p.Y-dst.Y >= p.X-dst.X:
+ p.append(UniqueY)
+ default:
+ p.append(UniqueX)
+ }
+ }
+ for p.X > dst.X {
+ p.append(UniqueX)
+ }
+ for p.Y > dst.Y {
+ p.append(UniqueY)
+ }
+ }
+}
+
+func (p *path) append(t EditType) {
+ p.es = append(p.es, t)
+ switch t {
+ case Identity, Modified:
+ p.add(p.dir, p.dir)
+ case UniqueX:
+ p.add(p.dir, 0)
+ case UniqueY:
+ p.add(0, p.dir)
+ }
+ debug.Update()
+}
+
+type point struct{ X, Y int }
+
+func (p *point) add(dx, dy int) { p.X += dx; p.Y += dy }
+
+// zigzag maps a consecutive sequence of integers to a zig-zag sequence.
+// [0 1 2 3 4 5 ...] => [0 -1 +1 -2 +2 ...]
+func zigzag(x int) int {
+ if x&1 != 0 {
+ x = ^x
+ }
+ return x >> 1
+}
@@ -0,0 +1,49 @@
+// Copyright 2017, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE.md file.
+
+// Package function identifies function types.
+package function
+
+import "reflect"
+
+type funcType int
+
+const (
+ _ funcType = iota
+
+ ttbFunc // func(T, T) bool
+ tibFunc // func(T, I) bool
+ trFunc // func(T) R
+
+ Equal = ttbFunc // func(T, T) bool
+ EqualAssignable = tibFunc // func(T, I) bool; encapsulates func(T, T) bool
+ Transformer = trFunc // func(T) R
+ ValueFilter = ttbFunc // func(T, T) bool
+ Less = ttbFunc // func(T, T) bool
+)
+
+var boolType = reflect.TypeOf(true)
+
+// IsType reports whether the reflect.Type is of the specified function type.
+func IsType(t reflect.Type, ft funcType) bool {
+ if t == nil || t.Kind() != reflect.Func || t.IsVariadic() {
+ return false
+ }
+ ni, no := t.NumIn(), t.NumOut()
+ switch ft {
+ case ttbFunc: // func(T, T) bool
+ if ni == 2 && no == 1 && t.In(0) == t.In(1) && t.Out(0) == boolType {
+ return true
+ }
+ case tibFunc: // func(T, I) bool
+ if ni == 2 && no == 1 && t.In(0).AssignableTo(t.In(1)) && t.Out(0) == boolType {
+ return true
+ }
+ case trFunc: // func(T) R
+ if ni == 1 && no == 1 {
+ return true
+ }
+ }
+ return false
+}
@@ -0,0 +1,277 @@
+// Copyright 2017, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE.md file.
+
+// Package value provides functionality for reflect.Value types.
+package value
+
+import (
+ "fmt"
+ "reflect"
+ "strconv"
+ "strings"
+ "unicode"
+)
+
+var stringerIface = reflect.TypeOf((*fmt.Stringer)(nil)).Elem()
+
+// Format formats the value v as a string.
+//
+// This is similar to fmt.Sprintf("%+v", v) except this:
+// * Prints the type unless it can be elided
+// * Avoids printing struct fields that are zero
+// * Prints a nil-slice as being nil, not empty
+// * Prints map entries in deterministic order
+func Format(v reflect.Value, conf FormatConfig) string {
+ conf.printType = true
+ conf.followPointers = true
+ conf.realPointers = true
+ return formatAny(v, conf, nil)
+}
+
+type FormatConfig struct {
+ UseStringer bool // Should the String method be used if available?
+ printType bool // Should we print the type before the value?
+ PrintPrimitiveType bool // Should we print the type of primitives?
+ followPointers bool // Should we recursively follow pointers?
+ realPointers bool // Should we print the real address of pointers?
+}
+
+func formatAny(v reflect.Value, conf FormatConfig, visited map[uintptr]bool) string {
+ // TODO: Should this be a multi-line printout in certain situations?
+
+ if !v.IsValid() {
+ return "<non-existent>"
+ }
+ if conf.UseStringer && v.Type().Implements(stringerIface) && v.CanInterface() {
+ if (v.Kind() == reflect.Ptr || v.Kind() == reflect.Interface) && v.IsNil() {
+ return "<nil>"
+ }
+
+ const stringerPrefix = "s" // Indicates that the String method was used
+ s := v.Interface().(fmt.Stringer).String()
+ return stringerPrefix + formatString(s)
+ }
+
+ switch v.Kind() {
+ case reflect.Bool:
+ return formatPrimitive(v.Type(), v.Bool(), conf)
+ case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+ return formatPrimitive(v.Type(), v.Int(), conf)
+ case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+ if v.Type().PkgPath() == "" || v.Kind() == reflect.Uintptr {
+ // Unnamed uints are usually bytes or words, so use hexadecimal.
+ return formatPrimitive(v.Type(), formatHex(v.Uint()), conf)
+ }
+ return formatPrimitive(v.Type(), v.Uint(), conf)
+ case reflect.Float32, reflect.Float64:
+ return formatPrimitive(v.Type(), v.Float(), conf)
+ case reflect.Complex64, reflect.Complex128:
+ return formatPrimitive(v.Type(), v.Complex(), conf)
+ case reflect.String:
+ return formatPrimitive(v.Type(), formatString(v.String()), conf)
+ case reflect.UnsafePointer, reflect.Chan, reflect.Func:
+ return formatPointer(v, conf)
+ case reflect.Ptr:
+ if v.IsNil() {
+ if conf.printType {
+ return fmt.Sprintf("(%v)(nil)", v.Type())
+ }
+ return "<nil>"
+ }
+ if visited[v.Pointer()] || !conf.followPointers {
+ return formatPointer(v, conf)
+ }
+ visited = insertPointer(visited, v.Pointer())
+ return "&" + formatAny(v.Elem(), conf, visited)
+ case reflect.Interface:
+ if v.IsNil() {
+ if conf.printType {
+ return fmt.Sprintf("%v(nil)", v.Type())
+ }
+ return "<nil>"
+ }
+ return formatAny(v.Elem(), conf, visited)
+ case reflect.Slice:
+ if v.IsNil() {
+ if conf.printType {
+ return fmt.Sprintf("%v(nil)", v.Type())
+ }
+ return "<nil>"
+ }
+ if visited[v.Pointer()] {
+ return formatPointer(v, conf)
+ }
+ visited = insertPointer(visited, v.Pointer())
+ fallthrough
+ case reflect.Array:
+ var ss []string
+ subConf := conf
+ subConf.printType = v.Type().Elem().Kind() == reflect.Interface
+ for i := 0; i < v.Len(); i++ {
+ s := formatAny(v.Index(i), subConf, visited)
+ ss = append(ss, s)
+ }
+ s := fmt.Sprintf("{%s}", strings.Join(ss, ", "))
+ if conf.printType {
+ return v.Type().String() + s
+ }
+ return s
+ case reflect.Map:
+ if v.IsNil() {
+ if conf.printType {
+ return fmt.Sprintf("%v(nil)", v.Type())
+ }
+ return "<nil>"
+ }
+ if visited[v.Pointer()] {
+ return formatPointer(v, conf)
+ }
+ visited = insertPointer(visited, v.Pointer())
+
+ var ss []string
+ keyConf, valConf := conf, conf
+ keyConf.printType = v.Type().Key().Kind() == reflect.Interface
+ keyConf.followPointers = false
+ valConf.printType = v.Type().Elem().Kind() == reflect.Interface
+ for _, k := range SortKeys(v.MapKeys()) {
+ sk := formatAny(k, keyConf, visited)
+ sv := formatAny(v.MapIndex(k), valConf, visited)
+ ss = append(ss, fmt.Sprintf("%s: %s", sk, sv))
+ }
+ s := fmt.Sprintf("{%s}", strings.Join(ss, ", "))
+ if conf.printType {
+ return v.Type().String() + s
+ }
+ return s
+ case reflect.Struct:
+ var ss []string
+ subConf := conf
+ subConf.printType = true
+ for i := 0; i < v.NumField(); i++ {
+ vv := v.Field(i)
+ if isZero(vv) {
+ continue // Elide zero value fields
+ }
+ name := v.Type().Field(i).Name
+ subConf.UseStringer = conf.UseStringer
+ s := formatAny(vv, subConf, visited)
+ ss = append(ss, fmt.Sprintf("%s: %s", name, s))
+ }
+ s := fmt.Sprintf("{%s}", strings.Join(ss, ", "))
+ if conf.printType {
+ return v.Type().String() + s
+ }
+ return s
+ default:
+ panic(fmt.Sprintf("%v kind not handled", v.Kind()))
+ }
+}
+
+func formatString(s string) string {
+ // Use quoted string if it the same length as a raw string literal.
+ // Otherwise, attempt to use the raw string form.
+ qs := strconv.Quote(s)
+ if len(qs) == 1+len(s)+1 {
+ return qs
+ }
+
+ // Disallow newlines to ensure output is a single line.
+ // Only allow printable runes for readability purposes.
+ rawInvalid := func(r rune) bool {
+ return r == '`' || r == '\n' || !unicode.IsPrint(r)
+ }
+ if strings.IndexFunc(s, rawInvalid) < 0 {
+ return "`" + s + "`"
+ }
+ return qs
+}
+
+func formatPrimitive(t reflect.Type, v interface{}, conf FormatConfig) string {
+ if conf.printType && (conf.PrintPrimitiveType || t.PkgPath() != "") {
+ return fmt.Sprintf("%v(%v)", t, v)
+ }
+ return fmt.Sprintf("%v", v)
+}
+
+func formatPointer(v reflect.Value, conf FormatConfig) string {
+ p := v.Pointer()
+ if !conf.realPointers {
+ p = 0 // For deterministic printing purposes
+ }
+ s := formatHex(uint64(p))
+ if conf.printType {
+ return fmt.Sprintf("(%v)(%s)", v.Type(), s)
+ }
+ return s
+}
+
+func formatHex(u uint64) string {
+ var f string
+ switch {
+ case u <= 0xff:
+ f = "0x%02x"
+ case u <= 0xffff:
+ f = "0x%04x"
+ case u <= 0xffffff:
+ f = "0x%06x"
+ case u <= 0xffffffff:
+ f = "0x%08x"
+ case u <= 0xffffffffff:
+ f = "0x%010x"
+ case u <= 0xffffffffffff:
+ f = "0x%012x"
+ case u <= 0xffffffffffffff:
+ f = "0x%014x"
+ case u <= 0xffffffffffffffff:
+ f = "0x%016x"
+ }
+ return fmt.Sprintf(f, u)
+}
+
+// insertPointer insert p into m, allocating m if necessary.
+func insertPointer(m map[uintptr]bool, p uintptr) map[uintptr]bool {
+ if m == nil {
+ m = make(map[uintptr]bool)
+ }
+ m[p] = true
+ return m
+}
+
+// isZero reports whether v is the zero value.
+// This does not rely on Interface and so can be used on unexported fields.
+func isZero(v reflect.Value) bool {
+ switch v.Kind() {
+ case reflect.Bool:
+ return v.Bool() == false
+ case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+ return v.Int() == 0
+ case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+ return v.Uint() == 0
+ case reflect.Float32, reflect.Float64:
+ return v.Float() == 0
+ case reflect.Complex64, reflect.Complex128:
+ return v.Complex() == 0
+ case reflect.String:
+ return v.String() == ""
+ case reflect.UnsafePointer:
+ return v.Pointer() == 0
+ case reflect.Chan, reflect.Func, reflect.Interface, reflect.Ptr, reflect.Map, reflect.Slice:
+ return v.IsNil()
+ case reflect.Array:
+ for i := 0; i < v.Len(); i++ {
+ if !isZero(v.Index(i)) {
+ return false
+ }
+ }
+ return true
+ case reflect.Struct:
+ for i := 0; i < v.NumField(); i++ {
+ if !isZero(v.Field(i)) {
+ return false
+ }
+ }
+ return true
+ }
+ return false
+}
@@ -0,0 +1,111 @@
+// Copyright 2017, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE.md file.
+
+package value
+
+import (
+ "fmt"
+ "math"
+ "reflect"
+ "sort"
+)
+
+// SortKeys sorts a list of map keys, deduplicating keys if necessary.
+// The type of each value must be comparable.
+func SortKeys(vs []reflect.Value) []reflect.Value {
+ if len(vs) == 0 {
+ return vs
+ }
+
+ // Sort the map keys.
+ sort.Sort(valueSorter(vs))
+
+ // Deduplicate keys (fails for NaNs).
+ vs2 := vs[:1]
+ for _, v := range vs[1:] {
+ if isLess(vs2[len(vs2)-1], v) {
+ vs2 = append(vs2, v)
+ }
+ }
+ return vs2
+}
+
+// TODO: Use sort.Slice once Google AppEngine is on Go1.8 or above.
+type valueSorter []reflect.Value
+
+func (vs valueSorter) Len() int { return len(vs) }
+func (vs valueSorter) Less(i, j int) bool { return isLess(vs[i], vs[j]) }
+func (vs valueSorter) Swap(i, j int) { vs[i], vs[j] = vs[j], vs[i] }
+
+// isLess is a generic function for sorting arbitrary map keys.
+// The inputs must be of the same type and must be comparable.
+func isLess(x, y reflect.Value) bool {
+ switch x.Type().Kind() {
+ case reflect.Bool:
+ return !x.Bool() && y.Bool()
+ case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+ return x.Int() < y.Int()
+ case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+ return x.Uint() < y.Uint()
+ case reflect.Float32, reflect.Float64:
+ fx, fy := x.Float(), y.Float()
+ return fx < fy || math.IsNaN(fx) && !math.IsNaN(fy)
+ case reflect.Complex64, reflect.Complex128:
+ cx, cy := x.Complex(), y.Complex()
+ rx, ix, ry, iy := real(cx), imag(cx), real(cy), imag(cy)
+ if rx == ry || (math.IsNaN(rx) && math.IsNaN(ry)) {
+ return ix < iy || math.IsNaN(ix) && !math.IsNaN(iy)
+ }
+ return rx < ry || math.IsNaN(rx) && !math.IsNaN(ry)
+ case reflect.Ptr, reflect.UnsafePointer, reflect.Chan:
+ return x.Pointer() < y.Pointer()
+ case reflect.String:
+ return x.String() < y.String()
+ case reflect.Array:
+ for i := 0; i < x.Len(); i++ {
+ if isLess(x.Index(i), y.Index(i)) {
+ return true
+ }
+ if isLess(y.Index(i), x.Index(i)) {
+ return false
+ }
+ }
+ return false
+ case reflect.Struct:
+ for i := 0; i < x.NumField(); i++ {
+ if isLess(x.Field(i), y.Field(i)) {
+ return true
+ }
+ if isLess(y.Field(i), x.Field(i)) {
+ return false
+ }
+ }
+ return false
+ case reflect.Interface:
+ vx, vy := x.Elem(), y.Elem()
+ if !vx.IsValid() || !vy.IsValid() {
+ return !vx.IsValid() && vy.IsValid()
+ }
+ tx, ty := vx.Type(), vy.Type()
+ if tx == ty {
+ return isLess(x.Elem(), y.Elem())
+ }
+ if tx.Kind() != ty.Kind() {
+ return vx.Kind() < vy.Kind()
+ }
+ if tx.String() != ty.String() {
+ return tx.String() < ty.String()
+ }
+ if tx.PkgPath() != ty.PkgPath() {
+ return tx.PkgPath() < ty.PkgPath()
+ }
+ // This can happen in rare situations, so we fallback to just comparing
+ // the unique pointer for a reflect.Type. This guarantees deterministic
+ // ordering within a program, but it is obviously not stable.
+ return reflect.ValueOf(vx.Type()).Pointer() < reflect.ValueOf(vy.Type()).Pointer()
+ default:
+ // Must be Func, Map, or Slice; which are not comparable.
+ panic(fmt.Sprintf("%T is not comparable", x.Type()))
+ }
+}
@@ -0,0 +1,453 @@
+// Copyright 2017, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE.md file.
+
+package cmp
+
+import (
+ "fmt"
+ "reflect"
+ "runtime"
+ "strings"
+
+ "github.com/google/go-cmp/cmp/internal/function"
+)
+
+// Option configures for specific behavior of Equal and Diff. In particular,
+// the fundamental Option functions (Ignore, Transformer, and Comparer),
+// configure how equality is determined.
+//
+// The fundamental options may be composed with filters (FilterPath and
+// FilterValues) to control the scope over which they are applied.
+//
+// The cmp/cmpopts package provides helper functions for creating options that
+// may be used with Equal and Diff.
+type Option interface {
+ // filter applies all filters and returns the option that remains.
+ // Each option may only read s.curPath and call s.callTTBFunc.
+ //
+ // An Options is returned only if multiple comparers or transformers
+ // can apply simultaneously and will only contain values of those types
+ // or sub-Options containing values of those types.
+ filter(s *state, vx, vy reflect.Value, t reflect.Type) applicableOption
+}
+
+// applicableOption represents the following types:
+// Fundamental: ignore | invalid | *comparer | *transformer
+// Grouping: Options
+type applicableOption interface {
+ Option
+
+ // apply executes the option, which may mutate s or panic.
+ apply(s *state, vx, vy reflect.Value)
+}
+
+// coreOption represents the following types:
+// Fundamental: ignore | invalid | *comparer | *transformer
+// Filters: *pathFilter | *valuesFilter
+type coreOption interface {
+ Option
+ isCore()
+}
+
+type core struct{}
+
+func (core) isCore() {}
+
+// Options is a list of Option values that also satisfies the Option interface.
+// Helper comparison packages may return an Options value when packing multiple
+// Option values into a single Option. When this package processes an Options,
+// it will be implicitly expanded into a flat list.
+//
+// Applying a filter on an Options is equivalent to applying that same filter
+// on all individual options held within.
+type Options []Option
+
+func (opts Options) filter(s *state, vx, vy reflect.Value, t reflect.Type) (out applicableOption) {
+ for _, opt := range opts {
+ switch opt := opt.filter(s, vx, vy, t); opt.(type) {
+ case ignore:
+ return ignore{} // Only ignore can short-circuit evaluation
+ case invalid:
+ out = invalid{} // Takes precedence over comparer or transformer
+ case *comparer, *transformer, Options:
+ switch out.(type) {
+ case nil:
+ out = opt
+ case invalid:
+ // Keep invalid
+ case *comparer, *transformer, Options:
+ out = Options{out, opt} // Conflicting comparers or transformers
+ }
+ }
+ }
+ return out
+}
+
+func (opts Options) apply(s *state, _, _ reflect.Value) {
+ const warning = "ambiguous set of applicable options"
+ const help = "consider using filters to ensure at most one Comparer or Transformer may apply"
+ var ss []string
+ for _, opt := range flattenOptions(nil, opts) {
+ ss = append(ss, fmt.Sprint(opt))
+ }
+ set := strings.Join(ss, "\n\t")
+ panic(fmt.Sprintf("%s at %#v:\n\t%s\n%s", warning, s.curPath, set, help))
+}
+
+func (opts Options) String() string {
+ var ss []string
+ for _, opt := range opts {
+ ss = append(ss, fmt.Sprint(opt))
+ }
+ return fmt.Sprintf("Options{%s}", strings.Join(ss, ", "))
+}
+
+// FilterPath returns a new Option where opt is only evaluated if filter f
+// returns true for the current Path in the value tree.
+//
+// The option passed in may be an Ignore, Transformer, Comparer, Options, or
+// a previously filtered Option.
+func FilterPath(f func(Path) bool, opt Option) Option {
+ if f == nil {
+ panic("invalid path filter function")
+ }
+ if opt := normalizeOption(opt); opt != nil {
+ return &pathFilter{fnc: f, opt: opt}
+ }
+ return nil
+}
+
+type pathFilter struct {
+ core
+ fnc func(Path) bool
+ opt Option
+}
+
+func (f pathFilter) filter(s *state, vx, vy reflect.Value, t reflect.Type) applicableOption {
+ if f.fnc(s.curPath) {
+ return f.opt.filter(s, vx, vy, t)
+ }
+ return nil
+}
+
+func (f pathFilter) String() string {
+ fn := getFuncName(reflect.ValueOf(f.fnc).Pointer())
+ return fmt.Sprintf("FilterPath(%s, %v)", fn, f.opt)
+}
+
+// FilterValues returns a new Option where opt is only evaluated if filter f,
+// which is a function of the form "func(T, T) bool", returns true for the
+// current pair of values being compared. If the type of the values is not
+// assignable to T, then this filter implicitly returns false.
+//
+// The filter function must be
+// symmetric (i.e., agnostic to the order of the inputs) and
+// deterministic (i.e., produces the same result when given the same inputs).
+// If T is an interface, it is possible that f is called with two values with
+// different concrete types that both implement T.
+//
+// The option passed in may be an Ignore, Transformer, Comparer, Options, or
+// a previously filtered Option.
+func FilterValues(f interface{}, opt Option) Option {
+ v := reflect.ValueOf(f)
+ if !function.IsType(v.Type(), function.ValueFilter) || v.IsNil() {
+ panic(fmt.Sprintf("invalid values filter function: %T", f))
+ }
+ if opt := normalizeOption(opt); opt != nil {
+ vf := &valuesFilter{fnc: v, opt: opt}
+ if ti := v.Type().In(0); ti.Kind() != reflect.Interface || ti.NumMethod() > 0 {
+ vf.typ = ti
+ }
+ return vf
+ }
+ return nil
+}
+
+type valuesFilter struct {
+ core
+ typ reflect.Type // T
+ fnc reflect.Value // func(T, T) bool
+ opt Option
+}
+
+func (f valuesFilter) filter(s *state, vx, vy reflect.Value, t reflect.Type) applicableOption {
+ if !vx.IsValid() || !vy.IsValid() {
+ return invalid{}
+ }
+ if (f.typ == nil || t.AssignableTo(f.typ)) && s.callTTBFunc(f.fnc, vx, vy) {
+ return f.opt.filter(s, vx, vy, t)
+ }
+ return nil
+}
+
+func (f valuesFilter) String() string {
+ fn := getFuncName(f.fnc.Pointer())
+ return fmt.Sprintf("FilterValues(%s, %v)", fn, f.opt)
+}
+
+// Ignore is an Option that causes all comparisons to be ignored.
+// This value is intended to be combined with FilterPath or FilterValues.
+// It is an error to pass an unfiltered Ignore option to Equal.
+func Ignore() Option { return ignore{} }
+
+type ignore struct{ core }
+
+func (ignore) isFiltered() bool { return false }
+func (ignore) filter(_ *state, _, _ reflect.Value, _ reflect.Type) applicableOption { return ignore{} }
+func (ignore) apply(_ *state, _, _ reflect.Value) { return }
+func (ignore) String() string { return "Ignore()" }
+
+// invalid is a sentinel Option type to indicate that some options could not
+// be evaluated due to unexported fields.
+type invalid struct{ core }
+
+func (invalid) filter(_ *state, _, _ reflect.Value, _ reflect.Type) applicableOption { return invalid{} }
+func (invalid) apply(s *state, _, _ reflect.Value) {
+ const help = "consider using AllowUnexported or cmpopts.IgnoreUnexported"
+ panic(fmt.Sprintf("cannot handle unexported field: %#v\n%s", s.curPath, help))
+}
+
+// Transformer returns an Option that applies a transformation function that
+// converts values of a certain type into that of another.
+//
+// The transformer f must be a function "func(T) R" that converts values of
+// type T to those of type R and is implicitly filtered to input values
+// assignable to T. The transformer must not mutate T in any way.
+//
+// To help prevent some cases of infinite recursive cycles applying the
+// same transform to the output of itself (e.g., in the case where the
+// input and output types are the same), an implicit filter is added such that
+// a transformer is applicable only if that exact transformer is not already
+// in the tail of the Path since the last non-Transform step.
+//
+// The name is a user provided label that is used as the Transform.Name in the
+// transformation PathStep. If empty, an arbitrary name is used.
+func Transformer(name string, f interface{}) Option {
+ v := reflect.ValueOf(f)
+ if !function.IsType(v.Type(), function.Transformer) || v.IsNil() {
+ panic(fmt.Sprintf("invalid transformer function: %T", f))
+ }
+ if name == "" {
+ name = "Ξ»" // Lambda-symbol as place-holder for anonymous transformer
+ }
+ if !isValid(name) {
+ panic(fmt.Sprintf("invalid name: %q", name))
+ }
+ tr := &transformer{name: name, fnc: reflect.ValueOf(f)}
+ if ti := v.Type().In(0); ti.Kind() != reflect.Interface || ti.NumMethod() > 0 {
+ tr.typ = ti
+ }
+ return tr
+}
+
+type transformer struct {
+ core
+ name string
+ typ reflect.Type // T
+ fnc reflect.Value // func(T) R
+}
+
+func (tr *transformer) isFiltered() bool { return tr.typ != nil }
+
+func (tr *transformer) filter(s *state, _, _ reflect.Value, t reflect.Type) applicableOption {
+ for i := len(s.curPath) - 1; i >= 0; i-- {
+ if t, ok := s.curPath[i].(*transform); !ok {
+ break // Hit most recent non-Transform step
+ } else if tr == t.trans {
+ return nil // Cannot directly use same Transform
+ }
+ }
+ if tr.typ == nil || t.AssignableTo(tr.typ) {
+ return tr
+ }
+ return nil
+}
+
+func (tr *transformer) apply(s *state, vx, vy reflect.Value) {
+ // Update path before calling the Transformer so that dynamic checks
+ // will use the updated path.
+ s.curPath.push(&transform{pathStep{tr.fnc.Type().Out(0)}, tr})
+ defer s.curPath.pop()
+
+ vx = s.callTRFunc(tr.fnc, vx)
+ vy = s.callTRFunc(tr.fnc, vy)
+ s.compareAny(vx, vy)
+}
+
+func (tr transformer) String() string {
+ return fmt.Sprintf("Transformer(%s, %s)", tr.name, getFuncName(tr.fnc.Pointer()))
+}
+
+// Comparer returns an Option that determines whether two values are equal
+// to each other.
+//
+// The comparer f must be a function "func(T, T) bool" and is implicitly
+// filtered to input values assignable to T. If T is an interface, it is
+// possible that f is called with two values of different concrete types that
+// both implement T.
+//
+// The equality function must be:
+// β’ Symmetric: equal(x, y) == equal(y, x)
+// β’ Deterministic: equal(x, y) == equal(x, y)
+// β’ Pure: equal(x, y) does not modify x or y
+func Comparer(f interface{}) Option {
+ v := reflect.ValueOf(f)
+ if !function.IsType(v.Type(), function.Equal) || v.IsNil() {
+ panic(fmt.Sprintf("invalid comparer function: %T", f))
+ }
+ cm := &comparer{fnc: v}
+ if ti := v.Type().In(0); ti.Kind() != reflect.Interface || ti.NumMethod() > 0 {
+ cm.typ = ti
+ }
+ return cm
+}
+
+type comparer struct {
+ core
+ typ reflect.Type // T
+ fnc reflect.Value // func(T, T) bool
+}
+
+func (cm *comparer) isFiltered() bool { return cm.typ != nil }
+
+func (cm *comparer) filter(_ *state, _, _ reflect.Value, t reflect.Type) applicableOption {
+ if cm.typ == nil || t.AssignableTo(cm.typ) {
+ return cm
+ }
+ return nil
+}
+
+func (cm *comparer) apply(s *state, vx, vy reflect.Value) {
+ eq := s.callTTBFunc(cm.fnc, vx, vy)
+ s.report(eq, vx, vy)
+}
+
+func (cm comparer) String() string {
+ return fmt.Sprintf("Comparer(%s)", getFuncName(cm.fnc.Pointer()))
+}
+
+// AllowUnexported returns an Option that forcibly allows operations on
+// unexported fields in certain structs, which are specified by passing in a
+// value of each struct type.
+//
+// Users of this option must understand that comparing on unexported fields
+// from external packages is not safe since changes in the internal
+// implementation of some external package may cause the result of Equal
+// to unexpectedly change. However, it may be valid to use this option on types
+// defined in an internal package where the semantic meaning of an unexported
+// field is in the control of the user.
+//
+// For some cases, a custom Comparer should be used instead that defines
+// equality as a function of the public API of a type rather than the underlying
+// unexported implementation.
+//
+// For example, the reflect.Type documentation defines equality to be determined
+// by the == operator on the interface (essentially performing a shallow pointer
+// comparison) and most attempts to compare *regexp.Regexp types are interested
+// in only checking that the regular expression strings are equal.
+// Both of these are accomplished using Comparers:
+//
+// Comparer(func(x, y reflect.Type) bool { return x == y })
+// Comparer(func(x, y *regexp.Regexp) bool { return x.String() == y.String() })
+//
+// In other cases, the cmpopts.IgnoreUnexported option can be used to ignore
+// all unexported fields on specified struct types.
+func AllowUnexported(types ...interface{}) Option {
+ if !supportAllowUnexported {
+ panic("AllowUnexported is not supported on purego builds, Google App Engine Standard, or GopherJS")
+ }
+ m := make(map[reflect.Type]bool)
+ for _, typ := range types {
+ t := reflect.TypeOf(typ)
+ if t.Kind() != reflect.Struct {
+ panic(fmt.Sprintf("invalid struct type: %T", typ))
+ }
+ m[t] = true
+ }
+ return visibleStructs(m)
+}
+
+type visibleStructs map[reflect.Type]bool
+
+func (visibleStructs) filter(_ *state, _, _ reflect.Value, _ reflect.Type) applicableOption {
+ panic("not implemented")
+}
+
+// reporter is an Option that configures how differences are reported.
+type reporter interface {
+ // TODO: Not exported yet.
+ //
+ // Perhaps add PushStep and PopStep and change Report to only accept
+ // a PathStep instead of the full-path? Adding a PushStep and PopStep makes
+ // it clear that we are traversing the value tree in a depth-first-search
+ // manner, which has an effect on how values are printed.
+
+ Option
+
+ // Report is called for every comparison made and will be provided with
+ // the two values being compared, the equality result, and the
+ // current path in the value tree. It is possible for x or y to be an
+ // invalid reflect.Value if one of the values is non-existent;
+ // which is possible with maps and slices.
+ Report(x, y reflect.Value, eq bool, p Path)
+}
+
+// normalizeOption normalizes the input options such that all Options groups
+// are flattened and groups with a single element are reduced to that element.
+// Only coreOptions and Options containing coreOptions are allowed.
+func normalizeOption(src Option) Option {
+ switch opts := flattenOptions(nil, Options{src}); len(opts) {
+ case 0:
+ return nil
+ case 1:
+ return opts[0]
+ default:
+ return opts
+ }
+}
+
+// flattenOptions copies all options in src to dst as a flat list.
+// Only coreOptions and Options containing coreOptions are allowed.
+func flattenOptions(dst, src Options) Options {
+ for _, opt := range src {
+ switch opt := opt.(type) {
+ case nil:
+ continue
+ case Options:
+ dst = flattenOptions(dst, opt)
+ case coreOption:
+ dst = append(dst, opt)
+ default:
+ panic(fmt.Sprintf("invalid option type: %T", opt))
+ }
+ }
+ return dst
+}
+
+// getFuncName returns a short function name from the pointer.
+// The string parsing logic works up until Go1.9.
+func getFuncName(p uintptr) string {
+ fnc := runtime.FuncForPC(p)
+ if fnc == nil {
+ return "<unknown>"
+ }
+ name := fnc.Name() // E.g., "long/path/name/mypkg.(mytype).(long/path/name/mypkg.myfunc)-fm"
+ if strings.HasSuffix(name, ")-fm") || strings.HasSuffix(name, ")Β·fm") {
+ // Strip the package name from method name.
+ name = strings.TrimSuffix(name, ")-fm")
+ name = strings.TrimSuffix(name, ")Β·fm")
+ if i := strings.LastIndexByte(name, '('); i >= 0 {
+ methodName := name[i+1:] // E.g., "long/path/name/mypkg.myfunc"
+ if j := strings.LastIndexByte(methodName, '.'); j >= 0 {
+ methodName = methodName[j+1:] // E.g., "myfunc"
+ }
+ name = name[:i] + methodName // E.g., "long/path/name/mypkg.(mytype)." + "myfunc"
+ }
+ }
+ if i := strings.LastIndexByte(name, '/'); i >= 0 {
+ // Strip the package name.
+ name = name[i+1:] // E.g., "mypkg.(mytype).myfunc"
+ }
+ return name
+}
@@ -0,0 +1,309 @@
+// Copyright 2017, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE.md file.
+
+package cmp
+
+import (
+ "fmt"
+ "reflect"
+ "strings"
+ "unicode"
+ "unicode/utf8"
+)
+
+type (
+ // Path is a list of PathSteps describing the sequence of operations to get
+ // from some root type to the current position in the value tree.
+ // The first Path element is always an operation-less PathStep that exists
+ // simply to identify the initial type.
+ //
+ // When traversing structs with embedded structs, the embedded struct will
+ // always be accessed as a field before traversing the fields of the
+ // embedded struct themselves. That is, an exported field from the
+ // embedded struct will never be accessed directly from the parent struct.
+ Path []PathStep
+
+ // PathStep is a union-type for specific operations to traverse
+ // a value's tree structure. Users of this package never need to implement
+ // these types as values of this type will be returned by this package.
+ PathStep interface {
+ String() string
+ Type() reflect.Type // Resulting type after performing the path step
+ isPathStep()
+ }
+
+ // SliceIndex is an index operation on a slice or array at some index Key.
+ SliceIndex interface {
+ PathStep
+ Key() int // May return -1 if in a split state
+
+ // SplitKeys returns the indexes for indexing into slices in the
+ // x and y values, respectively. These indexes may differ due to the
+ // insertion or removal of an element in one of the slices, causing
+ // all of the indexes to be shifted. If an index is -1, then that
+ // indicates that the element does not exist in the associated slice.
+ //
+ // Key is guaranteed to return -1 if and only if the indexes returned
+ // by SplitKeys are not the same. SplitKeys will never return -1 for
+ // both indexes.
+ SplitKeys() (x int, y int)
+
+ isSliceIndex()
+ }
+ // MapIndex is an index operation on a map at some index Key.
+ MapIndex interface {
+ PathStep
+ Key() reflect.Value
+ isMapIndex()
+ }
+ // TypeAssertion represents a type assertion on an interface.
+ TypeAssertion interface {
+ PathStep
+ isTypeAssertion()
+ }
+ // StructField represents a struct field access on a field called Name.
+ StructField interface {
+ PathStep
+ Name() string
+ Index() int
+ isStructField()
+ }
+ // Indirect represents pointer indirection on the parent type.
+ Indirect interface {
+ PathStep
+ isIndirect()
+ }
+ // Transform is a transformation from the parent type to the current type.
+ Transform interface {
+ PathStep
+ Name() string
+ Func() reflect.Value
+
+ // Option returns the originally constructed Transformer option.
+ // The == operator can be used to detect the exact option used.
+ Option() Option
+
+ isTransform()
+ }
+)
+
+func (pa *Path) push(s PathStep) {
+ *pa = append(*pa, s)
+}
+
+func (pa *Path) pop() {
+ *pa = (*pa)[:len(*pa)-1]
+}
+
+// Last returns the last PathStep in the Path.
+// If the path is empty, this returns a non-nil PathStep that reports a nil Type.
+func (pa Path) Last() PathStep {
+ return pa.Index(-1)
+}
+
+// Index returns the ith step in the Path and supports negative indexing.
+// A negative index starts counting from the tail of the Path such that -1
+// refers to the last step, -2 refers to the second-to-last step, and so on.
+// If index is invalid, this returns a non-nil PathStep that reports a nil Type.
+func (pa Path) Index(i int) PathStep {
+ if i < 0 {
+ i = len(pa) + i
+ }
+ if i < 0 || i >= len(pa) {
+ return pathStep{}
+ }
+ return pa[i]
+}
+
+// String returns the simplified path to a node.
+// The simplified path only contains struct field accesses.
+//
+// For example:
+// MyMap.MySlices.MyField
+func (pa Path) String() string {
+ var ss []string
+ for _, s := range pa {
+ if _, ok := s.(*structField); ok {
+ ss = append(ss, s.String())
+ }
+ }
+ return strings.TrimPrefix(strings.Join(ss, ""), ".")
+}
+
+// GoString returns the path to a specific node using Go syntax.
+//
+// For example:
+// (*root.MyMap["key"].(*mypkg.MyStruct).MySlices)[2][3].MyField
+func (pa Path) GoString() string {
+ var ssPre, ssPost []string
+ var numIndirect int
+ for i, s := range pa {
+ var nextStep PathStep
+ if i+1 < len(pa) {
+ nextStep = pa[i+1]
+ }
+ switch s := s.(type) {
+ case *indirect:
+ numIndirect++
+ pPre, pPost := "(", ")"
+ switch nextStep.(type) {
+ case *indirect:
+ continue // Next step is indirection, so let them batch up
+ case *structField:
+ numIndirect-- // Automatic indirection on struct fields
+ case nil:
+ pPre, pPost = "", "" // Last step; no need for parenthesis
+ }
+ if numIndirect > 0 {
+ ssPre = append(ssPre, pPre+strings.Repeat("*", numIndirect))
+ ssPost = append(ssPost, pPost)
+ }
+ numIndirect = 0
+ continue
+ case *transform:
+ ssPre = append(ssPre, s.trans.name+"(")
+ ssPost = append(ssPost, ")")
+ continue
+ case *typeAssertion:
+ // As a special-case, elide type assertions on anonymous types
+ // since they are typically generated dynamically and can be very
+ // verbose. For example, some transforms return interface{} because
+ // of Go's lack of generics, but typically take in and return the
+ // exact same concrete type.
+ if s.Type().PkgPath() == "" {
+ continue
+ }
+ }
+ ssPost = append(ssPost, s.String())
+ }
+ for i, j := 0, len(ssPre)-1; i < j; i, j = i+1, j-1 {
+ ssPre[i], ssPre[j] = ssPre[j], ssPre[i]
+ }
+ return strings.Join(ssPre, "") + strings.Join(ssPost, "")
+}
+
+type (
+ pathStep struct {
+ typ reflect.Type
+ }
+
+ sliceIndex struct {
+ pathStep
+ xkey, ykey int
+ }
+ mapIndex struct {
+ pathStep
+ key reflect.Value
+ }
+ typeAssertion struct {
+ pathStep
+ }
+ structField struct {
+ pathStep
+ name string
+ idx int
+
+ // These fields are used for forcibly accessing an unexported field.
+ // pvx, pvy, and field are only valid if unexported is true.
+ unexported bool
+ force bool // Forcibly allow visibility
+ pvx, pvy reflect.Value // Parent values
+ field reflect.StructField // Field information
+ }
+ indirect struct {
+ pathStep
+ }
+ transform struct {
+ pathStep
+ trans *transformer
+ }
+)
+
+func (ps pathStep) Type() reflect.Type { return ps.typ }
+func (ps pathStep) String() string {
+ if ps.typ == nil {
+ return "<nil>"
+ }
+ s := ps.typ.String()
+ if s == "" || strings.ContainsAny(s, "{}\n") {
+ return "root" // Type too simple or complex to print
+ }
+ return fmt.Sprintf("{%s}", s)
+}
+
+func (si sliceIndex) String() string {
+ switch {
+ case si.xkey == si.ykey:
+ return fmt.Sprintf("[%d]", si.xkey)
+ case si.ykey == -1:
+ // [5->?] means "I don't know where X[5] went"
+ return fmt.Sprintf("[%d->?]", si.xkey)
+ case si.xkey == -1:
+ // [?->3] means "I don't know where Y[3] came from"
+ return fmt.Sprintf("[?->%d]", si.ykey)
+ default:
+ // [5->3] means "X[5] moved to Y[3]"
+ return fmt.Sprintf("[%d->%d]", si.xkey, si.ykey)
+ }
+}
+func (mi mapIndex) String() string { return fmt.Sprintf("[%#v]", mi.key) }
+func (ta typeAssertion) String() string { return fmt.Sprintf(".(%v)", ta.typ) }
+func (sf structField) String() string { return fmt.Sprintf(".%s", sf.name) }
+func (in indirect) String() string { return "*" }
+func (tf transform) String() string { return fmt.Sprintf("%s()", tf.trans.name) }
+
+func (si sliceIndex) Key() int {
+ if si.xkey != si.ykey {
+ return -1
+ }
+ return si.xkey
+}
+func (si sliceIndex) SplitKeys() (x, y int) { return si.xkey, si.ykey }
+func (mi mapIndex) Key() reflect.Value { return mi.key }
+func (sf structField) Name() string { return sf.name }
+func (sf structField) Index() int { return sf.idx }
+func (tf transform) Name() string { return tf.trans.name }
+func (tf transform) Func() reflect.Value { return tf.trans.fnc }
+func (tf transform) Option() Option { return tf.trans }
+
+func (pathStep) isPathStep() {}
+func (sliceIndex) isSliceIndex() {}
+func (mapIndex) isMapIndex() {}
+func (typeAssertion) isTypeAssertion() {}
+func (structField) isStructField() {}
+func (indirect) isIndirect() {}
+func (transform) isTransform() {}
+
+var (
+ _ SliceIndex = sliceIndex{}
+ _ MapIndex = mapIndex{}
+ _ TypeAssertion = typeAssertion{}
+ _ StructField = structField{}
+ _ Indirect = indirect{}
+ _ Transform = transform{}
+
+ _ PathStep = sliceIndex{}
+ _ PathStep = mapIndex{}
+ _ PathStep = typeAssertion{}
+ _ PathStep = structField{}
+ _ PathStep = indirect{}
+ _ PathStep = transform{}
+)
+
+// isExported reports whether the identifier is exported.
+func isExported(id string) bool {
+ r, _ := utf8.DecodeRuneInString(id)
+ return unicode.IsUpper(r)
+}
+
+// isValid reports whether the identifier is valid.
+// Empty and underscore-only strings are not valid.
+func isValid(id string) bool {
+ ok := id != "" && id != "_"
+ for j, c := range id {
+ ok = ok && (j > 0 || !unicode.IsDigit(c))
+ ok = ok && (c == '_' || unicode.IsLetter(c) || unicode.IsDigit(c))
+ }
+ return ok
+}
@@ -0,0 +1,53 @@
+// Copyright 2017, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE.md file.
+
+package cmp
+
+import (
+ "fmt"
+ "reflect"
+ "strings"
+
+ "github.com/google/go-cmp/cmp/internal/value"
+)
+
+type defaultReporter struct {
+ Option
+ diffs []string // List of differences, possibly truncated
+ ndiffs int // Total number of differences
+ nbytes int // Number of bytes in diffs
+ nlines int // Number of lines in diffs
+}
+
+var _ reporter = (*defaultReporter)(nil)
+
+func (r *defaultReporter) Report(x, y reflect.Value, eq bool, p Path) {
+ if eq {
+ return // Ignore equal results
+ }
+ const maxBytes = 4096
+ const maxLines = 256
+ r.ndiffs++
+ if r.nbytes < maxBytes && r.nlines < maxLines {
+ sx := value.Format(x, value.FormatConfig{UseStringer: true})
+ sy := value.Format(y, value.FormatConfig{UseStringer: true})
+ if sx == sy {
+ // Unhelpful output, so use more exact formatting.
+ sx = value.Format(x, value.FormatConfig{PrintPrimitiveType: true})
+ sy = value.Format(y, value.FormatConfig{PrintPrimitiveType: true})
+ }
+ s := fmt.Sprintf("%#v:\n\t-: %s\n\t+: %s\n", p, sx, sy)
+ r.diffs = append(r.diffs, s)
+ r.nbytes += len(s)
+ r.nlines += strings.Count(s, "\n")
+ }
+}
+
+func (r *defaultReporter) String() string {
+ s := strings.Join(r.diffs, "")
+ if r.ndiffs == len(r.diffs) {
+ return s
+ }
+ return fmt.Sprintf("%s... %d more differences ...", s, r.ndiffs-len(r.diffs))
+}
@@ -0,0 +1,15 @@
+// Copyright 2017, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE.md file.
+
+// +build purego appengine js
+
+package cmp
+
+import "reflect"
+
+const supportAllowUnexported = false
+
+func unsafeRetrieveField(reflect.Value, reflect.StructField) reflect.Value {
+ panic("unsafeRetrieveField is not implemented")
+}
@@ -0,0 +1,23 @@
+// Copyright 2017, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE.md file.
+
+// +build !purego,!appengine,!js
+
+package cmp
+
+import (
+ "reflect"
+ "unsafe"
+)
+
+const supportAllowUnexported = true
+
+// unsafeRetrieveField uses unsafe to forcibly retrieve any field from a struct
+// such that the value has read-write permissions.
+//
+// The parent struct, v, must be addressable, while f must be a StructField
+// describing the field to retrieve.
+func unsafeRetrieveField(v reflect.Value, f reflect.StructField) reflect.Value {
+ return reflect.NewAt(f.Type, unsafe.Pointer(v.UnsafeAddr()+f.Offset)).Elem()
+}
@@ -0,0 +1,202 @@
+
+ Apache License
+ Version 2.0, January 2004
+ http://www.apache.org/licenses/
+
+ TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+ 1. Definitions.
+
+ "License" shall mean the terms and conditions for use, reproduction,
+ and distribution as defined by Sections 1 through 9 of this document.
+
+ "Licensor" shall mean the copyright owner or entity authorized by
+ the copyright owner that is granting the License.
+
+ "Legal Entity" shall mean the union of the acting entity and all
+ other entities that control, are controlled by, or are under common
+ control with that entity. For the purposes of this definition,
+ "control" means (i) the power, direct or indirect, to cause the
+ direction or management of such entity, whether by contract or
+ otherwise, or (ii) ownership of fifty percent (50%) or more of the
+ outstanding shares, or (iii) beneficial ownership of such entity.
+
+ "You" (or "Your") shall mean an individual or Legal Entity
+ exercising permissions granted by this License.
+
+ "Source" form shall mean the preferred form for making modifications,
+ including but not limited to software source code, documentation
+ source, and configuration files.
+
+ "Object" form shall mean any form resulting from mechanical
+ transformation or translation of a Source form, including but
+ not limited to compiled object code, generated documentation,
+ and conversions to other media types.
+
+ "Work" shall mean the work of authorship, whether in Source or
+ Object form, made available under the License, as indicated by a
+ copyright notice that is included in or attached to the work
+ (an example is provided in the Appendix below).
+
+ "Derivative Works" shall mean any work, whether in Source or Object
+ form, that is based on (or derived from) the Work and for which the
+ editorial revisions, annotations, elaborations, or other modifications
+ represent, as a whole, an original work of authorship. For the purposes
+ of this License, Derivative Works shall not include works that remain
+ separable from, or merely link (or bind by name) to the interfaces of,
+ the Work and Derivative Works thereof.
+
+ "Contribution" shall mean any work of authorship, including
+ the original version of the Work and any modifications or additions
+ to that Work or Derivative Works thereof, that is intentionally
+ submitted to Licensor for inclusion in the Work by the copyright owner
+ or by an individual or Legal Entity authorized to submit on behalf of
+ the copyright owner. For the purposes of this definition, "submitted"
+ means any form of electronic, verbal, or written communication sent
+ to the Licensor or its representatives, including but not limited to
+ communication on electronic mailing lists, source code control systems,
+ and issue tracking systems that are managed by, or on behalf of, the
+ Licensor for the purpose of discussing and improving the Work, but
+ excluding communication that is conspicuously marked or otherwise
+ designated in writing by the copyright owner as "Not a Contribution."
+
+ "Contributor" shall mean Licensor and any individual or Legal Entity
+ on behalf of whom a Contribution has been received by Licensor and
+ subsequently incorporated within the Work.
+
+ 2. Grant of Copyright License. Subject to the terms and conditions of
+ this License, each Contributor hereby grants to You a perpetual,
+ worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+ copyright license to reproduce, prepare Derivative Works of,
+ publicly display, publicly perform, sublicense, and distribute the
+ Work and such Derivative Works in Source or Object form.
+
+ 3. Grant of Patent License. Subject to the terms and conditions of
+ this License, each Contributor hereby grants to You a perpetual,
+ worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+ (except as stated in this section) patent license to make, have made,
+ use, offer to sell, sell, import, and otherwise transfer the Work,
+ where such license applies only to those patent claims licensable
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+ Contribution(s) alone or by combination of their Contribution(s)
+ with the Work to which such Contribution(s) was submitted. If You
+ institute patent litigation against any entity (including a
+ cross-claim or counterclaim in a lawsuit) alleging that the Work
+ or a Contribution incorporated within the Work constitutes direct
+ or contributory patent infringement, then any patent licenses
+ granted to You under this License for that Work shall terminate
+ as of the date such litigation is filed.
+
+ 4. Redistribution. You may reproduce and distribute copies of the
+ Work or Derivative Works thereof in any medium, with or without
+ modifications, and in Source or Object form, provided that You
+ meet the following conditions:
+
+ (a) You must give any other recipients of the Work or
+ Derivative Works a copy of this License; and
+
+ (b) You must cause any modified files to carry prominent notices
+ stating that You changed the files; and
+
+ (c) You must retain, in the Source form of any Derivative Works
+ that You distribute, all copyright, patent, trademark, and
+ attribution notices from the Source form of the Work,
+ excluding those notices that do not pertain to any part of
+ the Derivative Works; and
+
+ (d) If the Work includes a "NOTICE" text file as part of its
+ distribution, then any Derivative Works that You distribute must
+ include a readable copy of the attribution notices contained
+ within such NOTICE file, excluding those notices that do not
+ pertain to any part of the Derivative Works, in at least one
+ of the following places: within a NOTICE text file distributed
+ as part of the Derivative Works; within the Source form or
+ documentation, if provided along with the Derivative Works; or,
+ within a display generated by the Derivative Works, if and
+ wherever such third-party notices normally appear. The contents
+ of the NOTICE file are for informational purposes only and
+ do not modify the License. You may add Your own attribution
+ notices within Derivative Works that You distribute, alongside
+ or as an addendum to the NOTICE text from the Work, provided
+ that such additional attribution notices cannot be construed
+ as modifying the License.
+
+ You may add Your own copyright statement to Your modifications and
+ may provide additional or different license terms and conditions
+ for use, reproduction, or distribution of Your modifications, or
+ for any such Derivative Works as a whole, provided Your use,
+ reproduction, and distribution of the Work otherwise complies with
+ the conditions stated in this License.
+
+ 5. Submission of Contributions. Unless You explicitly state otherwise,
+ any Contribution intentionally submitted for inclusion in the Work
+ by You to the Licensor shall be under the terms and conditions of
+ this License, without any additional terms or conditions.
+ Notwithstanding the above, nothing herein shall supersede or modify
+ the terms of any separate license agreement you may have executed
+ with Licensor regarding such Contributions.
+
+ 6. Trademarks. This License does not grant permission to use the trade
+ names, trademarks, service marks, or product names of the Licensor,
+ except as required for reasonable and customary use in describing the
+ origin of the Work and reproducing the content of the NOTICE file.
+
+ 7. Disclaimer of Warranty. Unless required by applicable law or
+ agreed to in writing, Licensor provides the Work (and each
+ Contributor provides its Contributions) on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+ implied, including, without limitation, any warranties or conditions
+ of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+ PARTICULAR PURPOSE. You are solely responsible for determining the
+ appropriateness of using or redistributing the Work and assume any
+ risks associated with Your exercise of permissions under this License.
+
+ 8. Limitation of Liability. In no event and under no legal theory,
+ whether in tort (including negligence), contract, or otherwise,
+ unless required by applicable law (such as deliberate and grossly
+ negligent acts) or agreed to in writing, shall any Contributor be
+ liable to You for damages, including any direct, indirect, special,
+ incidental, or consequential damages of any character arising as a
+ result of this License or out of the use or inability to use the
+ Work (including but not limited to damages for loss of goodwill,
+ work stoppage, computer failure or malfunction, or any and all
+ other commercial damages or losses), even if such Contributor
+ has been advised of the possibility of such damages.
+
+ 9. Accepting Warranty or Additional Liability. While redistributing
+ the Work or Derivative Works thereof, You may choose to offer,
+ and charge a fee for, acceptance of support, warranty, indemnity,
+ or other liability obligations and/or rights consistent with this
+ License. However, in accepting such obligations, You may act only
+ on Your own behalf and on Your sole responsibility, not on behalf
+ of any other Contributor, and only if You agree to indemnify,
+ defend, and hold each Contributor harmless for any liability
+ incurred by, or claims asserted against, such Contributor by reason
+ of your accepting any such warranty or additional liability.
+
+ END OF TERMS AND CONDITIONS
+
+ APPENDIX: How to apply the Apache License to your work.
+
+ To apply the Apache License to your work, attach the following
+ boilerplate notice, with the fields enclosed by brackets "[]"
+ replaced with your own identifying information. (Don't include
+ the brackets!) The text should be enclosed in the appropriate
+ comment syntax for the file format. We also recommend that a
+ file or class name and description of purpose be included on the
+ same "printed page" as the copyright notice for easier
+ identification within third-party archives.
+
+ Copyright [yyyy] [name of copyright owner]
+
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
@@ -0,0 +1,311 @@
+/*Package assert provides assertions for comparing expected values to actual
+values. When an assertion fails a helpful error message is printed.
+
+Assert and Check
+
+Assert() and Check() both accept a Comparison, and fail the test when the
+comparison fails. The one difference is that Assert() will end the test execution
+immediately (using t.FailNow()) whereas Check() will fail the test (using t.Fail()),
+return the value of the comparison, then proceed with the rest of the test case.
+
+Example usage
+
+The example below shows assert used with some common types.
+
+
+ import (
+ "testing"
+
+ "gotest.tools/assert"
+ is "gotest.tools/assert/cmp"
+ )
+
+ func TestEverything(t *testing.T) {
+ // booleans
+ assert.Assert(t, ok)
+ assert.Assert(t, !missing)
+
+ // primitives
+ assert.Equal(t, count, 1)
+ assert.Equal(t, msg, "the message")
+ assert.Assert(t, total != 10) // NotEqual
+
+ // errors
+ assert.NilError(t, closer.Close())
+ assert.Error(t, err, "the exact error message")
+ assert.ErrorContains(t, err, "includes this")
+ assert.ErrorType(t, err, os.IsNotExist)
+
+ // complex types
+ assert.DeepEqual(t, result, myStruct{Name: "title"})
+ assert.Assert(t, is.Len(items, 3))
+ assert.Assert(t, len(sequence) != 0) // NotEmpty
+ assert.Assert(t, is.Contains(mapping, "key"))
+
+ // pointers and interface
+ assert.Assert(t, is.Nil(ref))
+ assert.Assert(t, ref != nil) // NotNil
+ }
+
+Comparisons
+
+Package https://godoc.org/gotest.tools/assert/cmp provides
+many common comparisons. Additional comparisons can be written to compare
+values in other ways. See the example Assert (CustomComparison).
+
+Automated migration from testify
+
+gty-migrate-from-testify is a binary which can update source code which uses
+testify assertions to use the assertions provided by this package.
+
+See http://bit.do/cmd-gty-migrate-from-testify.
+
+
+*/
+package assert // import "gotest.tools/assert"
+
+import (
+ "fmt"
+ "go/ast"
+ "go/token"
+
+ gocmp "github.com/google/go-cmp/cmp"
+ "gotest.tools/assert/cmp"
+ "gotest.tools/internal/format"
+ "gotest.tools/internal/source"
+)
+
+// BoolOrComparison can be a bool, or cmp.Comparison. See Assert() for usage.
+type BoolOrComparison interface{}
+
+// TestingT is the subset of testing.T used by the assert package.
+type TestingT interface {
+ FailNow()
+ Fail()
+ Log(args ...interface{})
+}
+
+type helperT interface {
+ Helper()
+}
+
+const failureMessage = "assertion failed: "
+
+// nolint: gocyclo
+func assert(
+ t TestingT,
+ failer func(),
+ argSelector argSelector,
+ comparison BoolOrComparison,
+ msgAndArgs ...interface{},
+) bool {
+ if ht, ok := t.(helperT); ok {
+ ht.Helper()
+ }
+ var success bool
+ switch check := comparison.(type) {
+ case bool:
+ if check {
+ return true
+ }
+ logFailureFromBool(t, msgAndArgs...)
+
+ // Undocumented legacy comparison without Result type
+ case func() (success bool, message string):
+ success = runCompareFunc(t, check, msgAndArgs...)
+
+ case nil:
+ return true
+
+ case error:
+ msg := "error is not nil: "
+ t.Log(format.WithCustomMessage(failureMessage+msg+check.Error(), msgAndArgs...))
+
+ case cmp.Comparison:
+ success = runComparison(t, argSelector, check, msgAndArgs...)
+
+ case func() cmp.Result:
+ success = runComparison(t, argSelector, check, msgAndArgs...)
+
+ default:
+ t.Log(fmt.Sprintf("invalid Comparison: %v (%T)", check, check))
+ }
+
+ if success {
+ return true
+ }
+ failer()
+ return false
+}
+
+func runCompareFunc(
+ t TestingT,
+ f func() (success bool, message string),
+ msgAndArgs ...interface{},
+) bool {
+ if ht, ok := t.(helperT); ok {
+ ht.Helper()
+ }
+ if success, message := f(); !success {
+ t.Log(format.WithCustomMessage(failureMessage+message, msgAndArgs...))
+ return false
+ }
+ return true
+}
+
+func logFailureFromBool(t TestingT, msgAndArgs ...interface{}) {
+ if ht, ok := t.(helperT); ok {
+ ht.Helper()
+ }
+ const stackIndex = 3 // Assert()/Check(), assert(), formatFailureFromBool()
+ const comparisonArgPos = 1
+ args, err := source.CallExprArgs(stackIndex)
+ if err != nil {
+ t.Log(err.Error())
+ return
+ }
+
+ msg, err := boolFailureMessage(args[comparisonArgPos])
+ if err != nil {
+ t.Log(err.Error())
+ msg = "expression is false"
+ }
+
+ t.Log(format.WithCustomMessage(failureMessage+msg, msgAndArgs...))
+}
+
+func boolFailureMessage(expr ast.Expr) (string, error) {
+ if binaryExpr, ok := expr.(*ast.BinaryExpr); ok && binaryExpr.Op == token.NEQ {
+ x, err := source.FormatNode(binaryExpr.X)
+ if err != nil {
+ return "", err
+ }
+ y, err := source.FormatNode(binaryExpr.Y)
+ if err != nil {
+ return "", err
+ }
+ return x + " is " + y, nil
+ }
+
+ if unaryExpr, ok := expr.(*ast.UnaryExpr); ok && unaryExpr.Op == token.NOT {
+ x, err := source.FormatNode(unaryExpr.X)
+ if err != nil {
+ return "", err
+ }
+ return x + " is true", nil
+ }
+
+ formatted, err := source.FormatNode(expr)
+ if err != nil {
+ return "", err
+ }
+ return "expression is false: " + formatted, nil
+}
+
+// Assert performs a comparison. If the comparison fails the test is marked as
+// failed, a failure message is logged, and execution is stopped immediately.
+//
+// The comparison argument may be one of three types: bool, cmp.Comparison or
+// error.
+// When called with a bool the failure message will contain the literal source
+// code of the expression.
+// When called with a cmp.Comparison the comparison is responsible for producing
+// a helpful failure message.
+// When called with an error a nil value is considered success. A non-nil error
+// is a failure, and Error() is used as the failure message.
+func Assert(t TestingT, comparison BoolOrComparison, msgAndArgs ...interface{}) {
+ if ht, ok := t.(helperT); ok {
+ ht.Helper()
+ }
+ assert(t, t.FailNow, argsFromComparisonCall, comparison, msgAndArgs...)
+}
+
+// Check performs a comparison. If the comparison fails the test is marked as
+// failed, a failure message is logged, and Check returns false. Otherwise returns
+// true.
+//
+// See Assert for details about the comparison arg and failure messages.
+func Check(t TestingT, comparison BoolOrComparison, msgAndArgs ...interface{}) bool {
+ if ht, ok := t.(helperT); ok {
+ ht.Helper()
+ }
+ return assert(t, t.Fail, argsFromComparisonCall, comparison, msgAndArgs...)
+}
+
+// NilError fails the test immediately if err is not nil.
+// This is equivalent to Assert(t, err)
+func NilError(t TestingT, err error, msgAndArgs ...interface{}) {
+ if ht, ok := t.(helperT); ok {
+ ht.Helper()
+ }
+ assert(t, t.FailNow, argsAfterT, err, msgAndArgs...)
+}
+
+// Equal uses the == operator to assert two values are equal and fails the test
+// if they are not equal.
+//
+// If the comparison fails Equal will use the variable names for x and y as part
+// of the failure message to identify the actual and expected values.
+//
+// If either x or y are a multi-line string the failure message will include a
+// unified diff of the two values. If the values only differ by whitespace
+// the unified diff will be augmented by replacing whitespace characters with
+// visible characters to identify the whitespace difference.
+//
+// This is equivalent to Assert(t, cmp.Equal(x, y)).
+func Equal(t TestingT, x, y interface{}, msgAndArgs ...interface{}) {
+ if ht, ok := t.(helperT); ok {
+ ht.Helper()
+ }
+ assert(t, t.FailNow, argsAfterT, cmp.Equal(x, y), msgAndArgs...)
+}
+
+// DeepEqual uses google/go-cmp (http://bit.do/go-cmp) to assert two values are
+// equal and fails the test if they are not equal.
+//
+// Package https://godoc.org/gotest.tools/assert/opt provides some additional
+// commonly used Options.
+//
+// This is equivalent to Assert(t, cmp.DeepEqual(x, y)).
+func DeepEqual(t TestingT, x, y interface{}, opts ...gocmp.Option) {
+ if ht, ok := t.(helperT); ok {
+ ht.Helper()
+ }
+ assert(t, t.FailNow, argsAfterT, cmp.DeepEqual(x, y, opts...))
+}
+
+// Error fails the test if err is nil, or the error message is not the expected
+// message.
+// Equivalent to Assert(t, cmp.Error(err, message)).
+func Error(t TestingT, err error, message string, msgAndArgs ...interface{}) {
+ if ht, ok := t.(helperT); ok {
+ ht.Helper()
+ }
+ assert(t, t.FailNow, argsAfterT, cmp.Error(err, message), msgAndArgs...)
+}
+
+// ErrorContains fails the test if err is nil, or the error message does not
+// contain the expected substring.
+// Equivalent to Assert(t, cmp.ErrorContains(err, substring)).
+func ErrorContains(t TestingT, err error, substring string, msgAndArgs ...interface{}) {
+ if ht, ok := t.(helperT); ok {
+ ht.Helper()
+ }
+ assert(t, t.FailNow, argsAfterT, cmp.ErrorContains(err, substring), msgAndArgs...)
+}
+
+// ErrorType fails the test if err is nil, or err is not the expected type.
+//
+// Expected can be one of:
+// a func(error) bool which returns true if the error is the expected type,
+// an instance of (or a pointer to) a struct of the expected type,
+// a pointer to an interface the error is expected to implement,
+// a reflect.Type of the expected struct or interface.
+//
+// Equivalent to Assert(t, cmp.ErrorType(err, expected)).
+func ErrorType(t TestingT, err error, expected interface{}, msgAndArgs ...interface{}) {
+ if ht, ok := t.(helperT); ok {
+ ht.Helper()
+ }
+ assert(t, t.FailNow, argsAfterT, cmp.ErrorType(err, expected), msgAndArgs...)
+}
@@ -0,0 +1,312 @@
+/*Package cmp provides Comparisons for Assert and Check*/
+package cmp // import "gotest.tools/assert/cmp"
+
+import (
+ "fmt"
+ "reflect"
+ "strings"
+
+ "github.com/google/go-cmp/cmp"
+ "gotest.tools/internal/format"
+)
+
+// Comparison is a function which compares values and returns ResultSuccess if
+// the actual value matches the expected value. If the values do not match the
+// Result will contain a message about why it failed.
+type Comparison func() Result
+
+// DeepEqual compares two values using google/go-cmp (http://bit.do/go-cmp)
+// and succeeds if the values are equal.
+//
+// The comparison can be customized using comparison Options.
+// Package https://godoc.org/gotest.tools/assert/opt provides some additional
+// commonly used Options.
+func DeepEqual(x, y interface{}, opts ...cmp.Option) Comparison {
+ return func() (result Result) {
+ defer func() {
+ if panicmsg, handled := handleCmpPanic(recover()); handled {
+ result = ResultFailure(panicmsg)
+ }
+ }()
+ diff := cmp.Diff(x, y, opts...)
+ if diff == "" {
+ return ResultSuccess
+ }
+ return multiLineDiffResult(diff)
+ }
+}
+
+func handleCmpPanic(r interface{}) (string, bool) {
+ if r == nil {
+ return "", false
+ }
+ panicmsg, ok := r.(string)
+ if !ok {
+ panic(r)
+ }
+ switch {
+ case strings.HasPrefix(panicmsg, "cannot handle unexported field"):
+ return panicmsg, true
+ }
+ panic(r)
+}
+
+func toResult(success bool, msg string) Result {
+ if success {
+ return ResultSuccess
+ }
+ return ResultFailure(msg)
+}
+
+// Equal succeeds if x == y. See assert.Equal for full documentation.
+func Equal(x, y interface{}) Comparison {
+ return func() Result {
+ switch {
+ case x == y:
+ return ResultSuccess
+ case isMultiLineStringCompare(x, y):
+ diff := format.UnifiedDiff(format.DiffConfig{A: x.(string), B: y.(string)})
+ return multiLineDiffResult(diff)
+ }
+ return ResultFailureTemplate(`
+ {{- .Data.x}} (
+ {{- with callArg 0 }}{{ formatNode . }} {{end -}}
+ {{- printf "%T" .Data.x -}}
+ ) != {{ .Data.y}} (
+ {{- with callArg 1 }}{{ formatNode . }} {{end -}}
+ {{- printf "%T" .Data.y -}}
+ )`,
+ map[string]interface{}{"x": x, "y": y})
+ }
+}
+
+func isMultiLineStringCompare(x, y interface{}) bool {
+ strX, ok := x.(string)
+ if !ok {
+ return false
+ }
+ strY, ok := y.(string)
+ if !ok {
+ return false
+ }
+ return strings.Contains(strX, "\n") || strings.Contains(strY, "\n")
+}
+
+func multiLineDiffResult(diff string) Result {
+ return ResultFailureTemplate(`
+--- {{ with callArg 0 }}{{ formatNode . }}{{else}}β{{end}}
++++ {{ with callArg 1 }}{{ formatNode . }}{{else}}β{{end}}
+{{ .Data.diff }}`,
+ map[string]interface{}{"diff": diff})
+}
+
+// Len succeeds if the sequence has the expected length.
+func Len(seq interface{}, expected int) Comparison {
+ return func() (result Result) {
+ defer func() {
+ if e := recover(); e != nil {
+ result = ResultFailure(fmt.Sprintf("type %T does not have a length", seq))
+ }
+ }()
+ value := reflect.ValueOf(seq)
+ length := value.Len()
+ if length == expected {
+ return ResultSuccess
+ }
+ msg := fmt.Sprintf("expected %s (length %d) to have length %d", seq, length, expected)
+ return ResultFailure(msg)
+ }
+}
+
+// Contains succeeds if item is in collection. Collection may be a string, map,
+// slice, or array.
+//
+// If collection is a string, item must also be a string, and is compared using
+// strings.Contains().
+// If collection is a Map, contains will succeed if item is a key in the map.
+// If collection is a slice or array, item is compared to each item in the
+// sequence using reflect.DeepEqual().
+func Contains(collection interface{}, item interface{}) Comparison {
+ return func() Result {
+ colValue := reflect.ValueOf(collection)
+ if !colValue.IsValid() {
+ return ResultFailure(fmt.Sprintf("nil does not contain items"))
+ }
+ msg := fmt.Sprintf("%v does not contain %v", collection, item)
+
+ itemValue := reflect.ValueOf(item)
+ switch colValue.Type().Kind() {
+ case reflect.String:
+ if itemValue.Type().Kind() != reflect.String {
+ return ResultFailure("string may only contain strings")
+ }
+ return toResult(
+ strings.Contains(colValue.String(), itemValue.String()),
+ fmt.Sprintf("string %q does not contain %q", collection, item))
+
+ case reflect.Map:
+ if itemValue.Type() != colValue.Type().Key() {
+ return ResultFailure(fmt.Sprintf(
+ "%v can not contain a %v key", colValue.Type(), itemValue.Type()))
+ }
+ return toResult(colValue.MapIndex(itemValue).IsValid(), msg)
+
+ case reflect.Slice, reflect.Array:
+ for i := 0; i < colValue.Len(); i++ {
+ if reflect.DeepEqual(colValue.Index(i).Interface(), item) {
+ return ResultSuccess
+ }
+ }
+ return ResultFailure(msg)
+ default:
+ return ResultFailure(fmt.Sprintf("type %T does not contain items", collection))
+ }
+ }
+}
+
+// Panics succeeds if f() panics.
+func Panics(f func()) Comparison {
+ return func() (result Result) {
+ defer func() {
+ if err := recover(); err != nil {
+ result = ResultSuccess
+ }
+ }()
+ f()
+ return ResultFailure("did not panic")
+ }
+}
+
+// Error succeeds if err is a non-nil error, and the error message equals the
+// expected message.
+func Error(err error, message string) Comparison {
+ return func() Result {
+ switch {
+ case err == nil:
+ return ResultFailure("expected an error, got nil")
+ case err.Error() != message:
+ return ResultFailure(fmt.Sprintf(
+ "expected error %q, got %+v", message, err))
+ }
+ return ResultSuccess
+ }
+}
+
+// ErrorContains succeeds if err is a non-nil error, and the error message contains
+// the expected substring.
+func ErrorContains(err error, substring string) Comparison {
+ return func() Result {
+ switch {
+ case err == nil:
+ return ResultFailure("expected an error, got nil")
+ case !strings.Contains(err.Error(), substring):
+ return ResultFailure(fmt.Sprintf(
+ "expected error to contain %q, got %+v", substring, err))
+ }
+ return ResultSuccess
+ }
+}
+
+// Nil succeeds if obj is a nil interface, pointer, or function.
+//
+// Use NilError() for comparing errors. Use Len(obj, 0) for comparing slices,
+// maps, and channels.
+func Nil(obj interface{}) Comparison {
+ msgFunc := func(value reflect.Value) string {
+ return fmt.Sprintf("%v (type %s) is not nil", reflect.Indirect(value), value.Type())
+ }
+ return isNil(obj, msgFunc)
+}
+
+func isNil(obj interface{}, msgFunc func(reflect.Value) string) Comparison {
+ return func() Result {
+ if obj == nil {
+ return ResultSuccess
+ }
+ value := reflect.ValueOf(obj)
+ kind := value.Type().Kind()
+ if kind >= reflect.Chan && kind <= reflect.Slice {
+ if value.IsNil() {
+ return ResultSuccess
+ }
+ return ResultFailure(msgFunc(value))
+ }
+
+ return ResultFailure(fmt.Sprintf("%v (type %s) can not be nil", value, value.Type()))
+ }
+}
+
+// ErrorType succeeds if err is not nil and is of the expected type.
+//
+// Expected can be one of:
+// a func(error) bool which returns true if the error is the expected type,
+// an instance of (or a pointer to) a struct of the expected type,
+// a pointer to an interface the error is expected to implement,
+// a reflect.Type of the expected struct or interface.
+func ErrorType(err error, expected interface{}) Comparison {
+ return func() Result {
+ switch expectedType := expected.(type) {
+ case func(error) bool:
+ return cmpErrorTypeFunc(err, expectedType)
+ case reflect.Type:
+ if expectedType.Kind() == reflect.Interface {
+ return cmpErrorTypeImplementsType(err, expectedType)
+ }
+ return cmpErrorTypeEqualType(err, expectedType)
+ case nil:
+ return ResultFailure(fmt.Sprintf("invalid type for expected: nil"))
+ }
+
+ expectedType := reflect.TypeOf(expected)
+ switch {
+ case expectedType.Kind() == reflect.Struct, isPtrToStruct(expectedType):
+ return cmpErrorTypeEqualType(err, expectedType)
+ case isPtrToInterface(expectedType):
+ return cmpErrorTypeImplementsType(err, expectedType.Elem())
+ }
+ return ResultFailure(fmt.Sprintf("invalid type for expected: %T", expected))
+ }
+}
+
+func cmpErrorTypeFunc(err error, f func(error) bool) Result {
+ if f(err) {
+ return ResultSuccess
+ }
+ actual := "nil"
+ if err != nil {
+ actual = fmt.Sprintf("%s (%T)", err, err)
+ }
+ return ResultFailureTemplate(`error is {{ .Data.actual }}
+ {{- with callArg 1 }}, not {{ formatNode . }}{{end -}}`,
+ map[string]interface{}{"actual": actual})
+}
+
+func cmpErrorTypeEqualType(err error, expectedType reflect.Type) Result {
+ if err == nil {
+ return ResultFailure(fmt.Sprintf("error is nil, not %s", expectedType))
+ }
+ errValue := reflect.ValueOf(err)
+ if errValue.Type() == expectedType {
+ return ResultSuccess
+ }
+ return ResultFailure(fmt.Sprintf("error is %s (%T), not %s", err, err, expectedType))
+}
+
+func cmpErrorTypeImplementsType(err error, expectedType reflect.Type) Result {
+ if err == nil {
+ return ResultFailure(fmt.Sprintf("error is nil, not %s", expectedType))
+ }
+ errValue := reflect.ValueOf(err)
+ if errValue.Type().Implements(expectedType) {
+ return ResultSuccess
+ }
+ return ResultFailure(fmt.Sprintf("error is %s (%T), not %s", err, err, expectedType))
+}
+
+func isPtrToInterface(typ reflect.Type) bool {
+ return typ.Kind() == reflect.Ptr && typ.Elem().Kind() == reflect.Interface
+}
+
+func isPtrToStruct(typ reflect.Type) bool {
+ return typ.Kind() == reflect.Ptr && typ.Elem().Kind() == reflect.Struct
+}
@@ -0,0 +1,94 @@
+package cmp
+
+import (
+ "bytes"
+ "fmt"
+ "go/ast"
+ "text/template"
+
+ "gotest.tools/internal/source"
+)
+
+// Result of a Comparison.
+type Result interface {
+ Success() bool
+}
+
+type result struct {
+ success bool
+ message string
+}
+
+func (r result) Success() bool {
+ return r.success
+}
+
+func (r result) FailureMessage() string {
+ return r.message
+}
+
+// ResultSuccess is a constant which is returned by a ComparisonWithResult to
+// indicate success.
+var ResultSuccess = result{success: true}
+
+// ResultFailure returns a failed Result with a failure message.
+func ResultFailure(message string) Result {
+ return result{message: message}
+}
+
+// ResultFromError returns ResultSuccess if err is nil. Otherwise ResultFailure
+// is returned with the error message as the failure message.
+func ResultFromError(err error) Result {
+ if err == nil {
+ return ResultSuccess
+ }
+ return ResultFailure(err.Error())
+}
+
+type templatedResult struct {
+ success bool
+ template string
+ data map[string]interface{}
+}
+
+func (r templatedResult) Success() bool {
+ return r.success
+}
+
+func (r templatedResult) FailureMessage(args []ast.Expr) string {
+ msg, err := renderMessage(r, args)
+ if err != nil {
+ return fmt.Sprintf("failed to render failure message: %s", err)
+ }
+ return msg
+}
+
+// ResultFailureTemplate returns a Result with a template string and data which
+// can be used to format a failure message. The template may access data from .Data,
+// the comparison args with the callArg function, and the formatNode function may
+// be used to format the call args.
+func ResultFailureTemplate(template string, data map[string]interface{}) Result {
+ return templatedResult{template: template, data: data}
+}
+
+func renderMessage(result templatedResult, args []ast.Expr) (string, error) {
+ tmpl := template.New("failure").Funcs(template.FuncMap{
+ "formatNode": source.FormatNode,
+ "callArg": func(index int) ast.Expr {
+ if index >= len(args) {
+ return nil
+ }
+ return args[index]
+ },
+ })
+ var err error
+ tmpl, err = tmpl.Parse(result.template)
+ if err != nil {
+ return "", err
+ }
+ buf := new(bytes.Buffer)
+ err = tmpl.Execute(buf, map[string]interface{}{
+ "Data": result.data,
+ })
+ return buf.String(), err
+}
@@ -0,0 +1,107 @@
+package assert
+
+import (
+ "fmt"
+ "go/ast"
+
+ "gotest.tools/assert/cmp"
+ "gotest.tools/internal/format"
+ "gotest.tools/internal/source"
+)
+
+func runComparison(
+ t TestingT,
+ argSelector argSelector,
+ f cmp.Comparison,
+ msgAndArgs ...interface{},
+) bool {
+ if ht, ok := t.(helperT); ok {
+ ht.Helper()
+ }
+ result := f()
+ if result.Success() {
+ return true
+ }
+
+ var message string
+ switch typed := result.(type) {
+ case resultWithComparisonArgs:
+ const stackIndex = 3 // Assert/Check, assert, runComparison
+ args, err := source.CallExprArgs(stackIndex)
+ if err != nil {
+ t.Log(err.Error())
+ }
+ message = typed.FailureMessage(filterPrintableExpr(argSelector(args)))
+ case resultBasic:
+ message = typed.FailureMessage()
+ default:
+ message = fmt.Sprintf("comparison returned invalid Result type: %T", result)
+ }
+
+ t.Log(format.WithCustomMessage(failureMessage+message, msgAndArgs...))
+ return false
+}
+
+type resultWithComparisonArgs interface {
+ FailureMessage(args []ast.Expr) string
+}
+
+type resultBasic interface {
+ FailureMessage() string
+}
+
+// filterPrintableExpr filters the ast.Expr slice to only include Expr that are
+// easy to read when printed and contain relevant information to an assertion.
+//
+// Ident and SelectorExpr are included because they print nicely and the variable
+// names may provide additional context to their values.
+// BasicLit and CompositeLit are excluded because their source is equivalent to
+// their value, which is already available.
+// Other types are ignored for now, but could be added if they are relevant.
+func filterPrintableExpr(args []ast.Expr) []ast.Expr {
+ result := make([]ast.Expr, len(args))
+ for i, arg := range args {
+ if isShortPrintableExpr(arg) {
+ result[i] = arg
+ continue
+ }
+
+ if starExpr, ok := arg.(*ast.StarExpr); ok {
+ result[i] = starExpr.X
+ continue
+ }
+ result[i] = nil
+ }
+ return result
+}
+
+func isShortPrintableExpr(expr ast.Expr) bool {
+ switch expr.(type) {
+ case *ast.Ident, *ast.SelectorExpr, *ast.IndexExpr, *ast.SliceExpr:
+ return true
+ case *ast.BinaryExpr, *ast.UnaryExpr:
+ return true
+ default:
+ // CallExpr, ParenExpr, TypeAssertExpr, KeyValueExpr, StarExpr
+ return false
+ }
+}
+
+type argSelector func([]ast.Expr) []ast.Expr
+
+func argsAfterT(args []ast.Expr) []ast.Expr {
+ if len(args) < 1 {
+ return nil
+ }
+ return args[1:]
+}
+
+func argsFromComparisonCall(args []ast.Expr) []ast.Expr {
+ if len(args) < 1 {
+ return nil
+ }
+ if callExpr, ok := args[1].(*ast.CallExpr); ok {
+ return callExpr.Args
+ }
+ return nil
+}
@@ -0,0 +1,27 @@
+Copyright (c) 2013, Patrick Mezard
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+ Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+ Redistributions in binary form must reproduce the above copyright
+notice, this list of conditions and the following disclaimer in the
+documentation and/or other materials provided with the distribution.
+ The names of its contributors may not be used to endorse or promote
+products derived from this software without specific prior written
+permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
+IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
+PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
+TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
@@ -0,0 +1,420 @@
+/* Package difflib is a partial port of Python difflib module.
+
+Original source: https://github.com/pmezard/go-difflib
+
+This file is trimmed to only the parts used by this repository.
+*/
+package difflib // import "gotest.tools/internal/difflib"
+
+func min(a, b int) int {
+ if a < b {
+ return a
+ }
+ return b
+}
+
+func max(a, b int) int {
+ if a > b {
+ return a
+ }
+ return b
+}
+
+type Match struct {
+ A int
+ B int
+ Size int
+}
+
+type OpCode struct {
+ Tag byte
+ I1 int
+ I2 int
+ J1 int
+ J2 int
+}
+
+// SequenceMatcher compares sequence of strings. The basic
+// algorithm predates, and is a little fancier than, an algorithm
+// published in the late 1980's by Ratcliff and Obershelp under the
+// hyperbolic name "gestalt pattern matching". The basic idea is to find
+// the longest contiguous matching subsequence that contains no "junk"
+// elements (R-O doesn't address junk). The same idea is then applied
+// recursively to the pieces of the sequences to the left and to the right
+// of the matching subsequence. This does not yield minimal edit
+// sequences, but does tend to yield matches that "look right" to people.
+//
+// SequenceMatcher tries to compute a "human-friendly diff" between two
+// sequences. Unlike e.g. UNIX(tm) diff, the fundamental notion is the
+// longest *contiguous* & junk-free matching subsequence. That's what
+// catches peoples' eyes. The Windows(tm) windiff has another interesting
+// notion, pairing up elements that appear uniquely in each sequence.
+// That, and the method here, appear to yield more intuitive difference
+// reports than does diff. This method appears to be the least vulnerable
+// to synching up on blocks of "junk lines", though (like blank lines in
+// ordinary text files, or maybe "<P>" lines in HTML files). That may be
+// because this is the only method of the 3 that has a *concept* of
+// "junk" <wink>.
+//
+// Timing: Basic R-O is cubic time worst case and quadratic time expected
+// case. SequenceMatcher is quadratic time for the worst case and has
+// expected-case behavior dependent in a complicated way on how many
+// elements the sequences have in common; best case time is linear.
+type SequenceMatcher struct {
+ a []string
+ b []string
+ b2j map[string][]int
+ IsJunk func(string) bool
+ autoJunk bool
+ bJunk map[string]struct{}
+ matchingBlocks []Match
+ fullBCount map[string]int
+ bPopular map[string]struct{}
+ opCodes []OpCode
+}
+
+func NewMatcher(a, b []string) *SequenceMatcher {
+ m := SequenceMatcher{autoJunk: true}
+ m.SetSeqs(a, b)
+ return &m
+}
+
+// Set two sequences to be compared.
+func (m *SequenceMatcher) SetSeqs(a, b []string) {
+ m.SetSeq1(a)
+ m.SetSeq2(b)
+}
+
+// Set the first sequence to be compared. The second sequence to be compared is
+// not changed.
+//
+// SequenceMatcher computes and caches detailed information about the second
+// sequence, so if you want to compare one sequence S against many sequences,
+// use .SetSeq2(s) once and call .SetSeq1(x) repeatedly for each of the other
+// sequences.
+//
+// See also SetSeqs() and SetSeq2().
+func (m *SequenceMatcher) SetSeq1(a []string) {
+ if &a == &m.a {
+ return
+ }
+ m.a = a
+ m.matchingBlocks = nil
+ m.opCodes = nil
+}
+
+// Set the second sequence to be compared. The first sequence to be compared is
+// not changed.
+func (m *SequenceMatcher) SetSeq2(b []string) {
+ if &b == &m.b {
+ return
+ }
+ m.b = b
+ m.matchingBlocks = nil
+ m.opCodes = nil
+ m.fullBCount = nil
+ m.chainB()
+}
+
+func (m *SequenceMatcher) chainB() {
+ // Populate line -> index mapping
+ b2j := map[string][]int{}
+ for i, s := range m.b {
+ indices := b2j[s]
+ indices = append(indices, i)
+ b2j[s] = indices
+ }
+
+ // Purge junk elements
+ m.bJunk = map[string]struct{}{}
+ if m.IsJunk != nil {
+ junk := m.bJunk
+ for s, _ := range b2j {
+ if m.IsJunk(s) {
+ junk[s] = struct{}{}
+ }
+ }
+ for s, _ := range junk {
+ delete(b2j, s)
+ }
+ }
+
+ // Purge remaining popular elements
+ popular := map[string]struct{}{}
+ n := len(m.b)
+ if m.autoJunk && n >= 200 {
+ ntest := n/100 + 1
+ for s, indices := range b2j {
+ if len(indices) > ntest {
+ popular[s] = struct{}{}
+ }
+ }
+ for s, _ := range popular {
+ delete(b2j, s)
+ }
+ }
+ m.bPopular = popular
+ m.b2j = b2j
+}
+
+func (m *SequenceMatcher) isBJunk(s string) bool {
+ _, ok := m.bJunk[s]
+ return ok
+}
+
+// Find longest matching block in a[alo:ahi] and b[blo:bhi].
+//
+// If IsJunk is not defined:
+//
+// Return (i,j,k) such that a[i:i+k] is equal to b[j:j+k], where
+// alo <= i <= i+k <= ahi
+// blo <= j <= j+k <= bhi
+// and for all (i',j',k') meeting those conditions,
+// k >= k'
+// i <= i'
+// and if i == i', j <= j'
+//
+// In other words, of all maximal matching blocks, return one that
+// starts earliest in a, and of all those maximal matching blocks that
+// start earliest in a, return the one that starts earliest in b.
+//
+// If IsJunk is defined, first the longest matching block is
+// determined as above, but with the additional restriction that no
+// junk element appears in the block. Then that block is extended as
+// far as possible by matching (only) junk elements on both sides. So
+// the resulting block never matches on junk except as identical junk
+// happens to be adjacent to an "interesting" match.
+//
+// If no blocks match, return (alo, blo, 0).
+func (m *SequenceMatcher) findLongestMatch(alo, ahi, blo, bhi int) Match {
+ // CAUTION: stripping common prefix or suffix would be incorrect.
+ // E.g.,
+ // ab
+ // acab
+ // Longest matching block is "ab", but if common prefix is
+ // stripped, it's "a" (tied with "b"). UNIX(tm) diff does so
+ // strip, so ends up claiming that ab is changed to acab by
+ // inserting "ca" in the middle. That's minimal but unintuitive:
+ // "it's obvious" that someone inserted "ac" at the front.
+ // Windiff ends up at the same place as diff, but by pairing up
+ // the unique 'b's and then matching the first two 'a's.
+ besti, bestj, bestsize := alo, blo, 0
+
+ // find longest junk-free match
+ // during an iteration of the loop, j2len[j] = length of longest
+ // junk-free match ending with a[i-1] and b[j]
+ j2len := map[int]int{}
+ for i := alo; i != ahi; i++ {
+ // look at all instances of a[i] in b; note that because
+ // b2j has no junk keys, the loop is skipped if a[i] is junk
+ newj2len := map[int]int{}
+ for _, j := range m.b2j[m.a[i]] {
+ // a[i] matches b[j]
+ if j < blo {
+ continue
+ }
+ if j >= bhi {
+ break
+ }
+ k := j2len[j-1] + 1
+ newj2len[j] = k
+ if k > bestsize {
+ besti, bestj, bestsize = i-k+1, j-k+1, k
+ }
+ }
+ j2len = newj2len
+ }
+
+ // Extend the best by non-junk elements on each end. In particular,
+ // "popular" non-junk elements aren't in b2j, which greatly speeds
+ // the inner loop above, but also means "the best" match so far
+ // doesn't contain any junk *or* popular non-junk elements.
+ for besti > alo && bestj > blo && !m.isBJunk(m.b[bestj-1]) &&
+ m.a[besti-1] == m.b[bestj-1] {
+ besti, bestj, bestsize = besti-1, bestj-1, bestsize+1
+ }
+ for besti+bestsize < ahi && bestj+bestsize < bhi &&
+ !m.isBJunk(m.b[bestj+bestsize]) &&
+ m.a[besti+bestsize] == m.b[bestj+bestsize] {
+ bestsize += 1
+ }
+
+ // Now that we have a wholly interesting match (albeit possibly
+ // empty!), we may as well suck up the matching junk on each
+ // side of it too. Can't think of a good reason not to, and it
+ // saves post-processing the (possibly considerable) expense of
+ // figuring out what to do with it. In the case of an empty
+ // interesting match, this is clearly the right thing to do,
+ // because no other kind of match is possible in the regions.
+ for besti > alo && bestj > blo && m.isBJunk(m.b[bestj-1]) &&
+ m.a[besti-1] == m.b[bestj-1] {
+ besti, bestj, bestsize = besti-1, bestj-1, bestsize+1
+ }
+ for besti+bestsize < ahi && bestj+bestsize < bhi &&
+ m.isBJunk(m.b[bestj+bestsize]) &&
+ m.a[besti+bestsize] == m.b[bestj+bestsize] {
+ bestsize += 1
+ }
+
+ return Match{A: besti, B: bestj, Size: bestsize}
+}
+
+// Return list of triples describing matching subsequences.
+//
+// Each triple is of the form (i, j, n), and means that
+// a[i:i+n] == b[j:j+n]. The triples are monotonically increasing in
+// i and in j. It's also guaranteed that if (i, j, n) and (i', j', n') are
+// adjacent triples in the list, and the second is not the last triple in the
+// list, then i+n != i' or j+n != j'. IOW, adjacent triples never describe
+// adjacent equal blocks.
+//
+// The last triple is a dummy, (len(a), len(b), 0), and is the only
+// triple with n==0.
+func (m *SequenceMatcher) GetMatchingBlocks() []Match {
+ if m.matchingBlocks != nil {
+ return m.matchingBlocks
+ }
+
+ var matchBlocks func(alo, ahi, blo, bhi int, matched []Match) []Match
+ matchBlocks = func(alo, ahi, blo, bhi int, matched []Match) []Match {
+ match := m.findLongestMatch(alo, ahi, blo, bhi)
+ i, j, k := match.A, match.B, match.Size
+ if match.Size > 0 {
+ if alo < i && blo < j {
+ matched = matchBlocks(alo, i, blo, j, matched)
+ }
+ matched = append(matched, match)
+ if i+k < ahi && j+k < bhi {
+ matched = matchBlocks(i+k, ahi, j+k, bhi, matched)
+ }
+ }
+ return matched
+ }
+ matched := matchBlocks(0, len(m.a), 0, len(m.b), nil)
+
+ // It's possible that we have adjacent equal blocks in the
+ // matching_blocks list now.
+ nonAdjacent := []Match{}
+ i1, j1, k1 := 0, 0, 0
+ for _, b := range matched {
+ // Is this block adjacent to i1, j1, k1?
+ i2, j2, k2 := b.A, b.B, b.Size
+ if i1+k1 == i2 && j1+k1 == j2 {
+ // Yes, so collapse them -- this just increases the length of
+ // the first block by the length of the second, and the first
+ // block so lengthened remains the block to compare against.
+ k1 += k2
+ } else {
+ // Not adjacent. Remember the first block (k1==0 means it's
+ // the dummy we started with), and make the second block the
+ // new block to compare against.
+ if k1 > 0 {
+ nonAdjacent = append(nonAdjacent, Match{i1, j1, k1})
+ }
+ i1, j1, k1 = i2, j2, k2
+ }
+ }
+ if k1 > 0 {
+ nonAdjacent = append(nonAdjacent, Match{i1, j1, k1})
+ }
+
+ nonAdjacent = append(nonAdjacent, Match{len(m.a), len(m.b), 0})
+ m.matchingBlocks = nonAdjacent
+ return m.matchingBlocks
+}
+
+// Return list of 5-tuples describing how to turn a into b.
+//
+// Each tuple is of the form (tag, i1, i2, j1, j2). The first tuple
+// has i1 == j1 == 0, and remaining tuples have i1 == the i2 from the
+// tuple preceding it, and likewise for j1 == the previous j2.
+//
+// The tags are characters, with these meanings:
+//
+// 'r' (replace): a[i1:i2] should be replaced by b[j1:j2]
+//
+// 'd' (delete): a[i1:i2] should be deleted, j1==j2 in this case.
+//
+// 'i' (insert): b[j1:j2] should be inserted at a[i1:i1], i1==i2 in this case.
+//
+// 'e' (equal): a[i1:i2] == b[j1:j2]
+func (m *SequenceMatcher) GetOpCodes() []OpCode {
+ if m.opCodes != nil {
+ return m.opCodes
+ }
+ i, j := 0, 0
+ matching := m.GetMatchingBlocks()
+ opCodes := make([]OpCode, 0, len(matching))
+ for _, m := range matching {
+ // invariant: we've pumped out correct diffs to change
+ // a[:i] into b[:j], and the next matching block is
+ // a[ai:ai+size] == b[bj:bj+size]. So we need to pump
+ // out a diff to change a[i:ai] into b[j:bj], pump out
+ // the matching block, and move (i,j) beyond the match
+ ai, bj, size := m.A, m.B, m.Size
+ tag := byte(0)
+ if i < ai && j < bj {
+ tag = 'r'
+ } else if i < ai {
+ tag = 'd'
+ } else if j < bj {
+ tag = 'i'
+ }
+ if tag > 0 {
+ opCodes = append(opCodes, OpCode{tag, i, ai, j, bj})
+ }
+ i, j = ai+size, bj+size
+ // the list of matching blocks is terminated by a
+ // sentinel with size 0
+ if size > 0 {
+ opCodes = append(opCodes, OpCode{'e', ai, i, bj, j})
+ }
+ }
+ m.opCodes = opCodes
+ return m.opCodes
+}
+
+// Isolate change clusters by eliminating ranges with no changes.
+//
+// Return a generator of groups with up to n lines of context.
+// Each group is in the same format as returned by GetOpCodes().
+func (m *SequenceMatcher) GetGroupedOpCodes(n int) [][]OpCode {
+ if n < 0 {
+ n = 3
+ }
+ codes := m.GetOpCodes()
+ if len(codes) == 0 {
+ codes = []OpCode{OpCode{'e', 0, 1, 0, 1}}
+ }
+ // Fixup leading and trailing groups if they show no changes.
+ if codes[0].Tag == 'e' {
+ c := codes[0]
+ i1, i2, j1, j2 := c.I1, c.I2, c.J1, c.J2
+ codes[0] = OpCode{c.Tag, max(i1, i2-n), i2, max(j1, j2-n), j2}
+ }
+ if codes[len(codes)-1].Tag == 'e' {
+ c := codes[len(codes)-1]
+ i1, i2, j1, j2 := c.I1, c.I2, c.J1, c.J2
+ codes[len(codes)-1] = OpCode{c.Tag, i1, min(i2, i1+n), j1, min(j2, j1+n)}
+ }
+ nn := n + n
+ groups := [][]OpCode{}
+ group := []OpCode{}
+ for _, c := range codes {
+ i1, i2, j1, j2 := c.I1, c.I2, c.J1, c.J2
+ // End the current group and start a new one whenever
+ // there is a large range with no changes.
+ if c.Tag == 'e' && i2-i1 > nn {
+ group = append(group, OpCode{c.Tag, i1, min(i2, i1+n),
+ j1, min(j2, j1+n)})
+ groups = append(groups, group)
+ group = []OpCode{}
+ i1, j1 = max(i1, i2-n), max(j1, j2-n)
+ }
+ group = append(group, OpCode{c.Tag, i1, i2, j1, j2})
+ }
+ if len(group) > 0 && !(len(group) == 1 && group[0].Tag == 'e') {
+ groups = append(groups, group)
+ }
+ return groups
+}
@@ -0,0 +1,161 @@
+package format
+
+import (
+ "bytes"
+ "fmt"
+ "strings"
+ "unicode"
+
+ "gotest.tools/internal/difflib"
+)
+
+const (
+ contextLines = 2
+)
+
+// DiffConfig for a unified diff
+type DiffConfig struct {
+ A string
+ B string
+ From string
+ To string
+}
+
+// UnifiedDiff is a modified version of difflib.WriteUnifiedDiff with better
+// support for showing the whitespace differences.
+func UnifiedDiff(conf DiffConfig) string {
+ a := strings.SplitAfter(conf.A, "\n")
+ b := strings.SplitAfter(conf.B, "\n")
+ groups := difflib.NewMatcher(a, b).GetGroupedOpCodes(contextLines)
+ if len(groups) == 0 {
+ return ""
+ }
+
+ buf := new(bytes.Buffer)
+ writeFormat := func(format string, args ...interface{}) {
+ buf.WriteString(fmt.Sprintf(format, args...))
+ }
+ writeLine := func(prefix string, s string) {
+ buf.WriteString(prefix + s)
+ }
+ if hasWhitespaceDiffLines(groups, a, b) {
+ writeLine = visibleWhitespaceLine(writeLine)
+ }
+ formatHeader(writeFormat, conf)
+ for _, group := range groups {
+ formatRangeLine(writeFormat, group)
+ for _, opCode := range group {
+ in, out := a[opCode.I1:opCode.I2], b[opCode.J1:opCode.J2]
+ switch opCode.Tag {
+ case 'e':
+ formatLines(writeLine, " ", in)
+ case 'r':
+ formatLines(writeLine, "-", in)
+ formatLines(writeLine, "+", out)
+ case 'd':
+ formatLines(writeLine, "-", in)
+ case 'i':
+ formatLines(writeLine, "+", out)
+ }
+ }
+ }
+ return buf.String()
+}
+
+// hasWhitespaceDiffLines returns true if any diff groups is only different
+// because of whitespace characters.
+func hasWhitespaceDiffLines(groups [][]difflib.OpCode, a, b []string) bool {
+ for _, group := range groups {
+ in, out := new(bytes.Buffer), new(bytes.Buffer)
+ for _, opCode := range group {
+ if opCode.Tag == 'e' {
+ continue
+ }
+ for _, line := range a[opCode.I1:opCode.I2] {
+ in.WriteString(line)
+ }
+ for _, line := range b[opCode.J1:opCode.J2] {
+ out.WriteString(line)
+ }
+ }
+ if removeWhitespace(in.String()) == removeWhitespace(out.String()) {
+ return true
+ }
+ }
+ return false
+}
+
+func removeWhitespace(s string) string {
+ var result []rune
+ for _, r := range s {
+ if !unicode.IsSpace(r) {
+ result = append(result, r)
+ }
+ }
+ return string(result)
+}
+
+func visibleWhitespaceLine(ws func(string, string)) func(string, string) {
+ mapToVisibleSpace := func(r rune) rune {
+ switch r {
+ case '\n':
+ case ' ':
+ return 'Β·'
+ case '\t':
+ return 'β·'
+ case '\v':
+ return 'β½'
+ case '\r':
+ return 'β΅'
+ case '\f':
+ return 'β'
+ default:
+ if unicode.IsSpace(r) {
+ return 'οΏ½'
+ }
+ }
+ return r
+ }
+ return func(prefix, s string) {
+ ws(prefix, strings.Map(mapToVisibleSpace, s))
+ }
+}
+
+func formatHeader(wf func(string, ...interface{}), conf DiffConfig) {
+ if conf.From != "" || conf.To != "" {
+ wf("--- %s\n", conf.From)
+ wf("+++ %s\n", conf.To)
+ }
+}
+
+func formatRangeLine(wf func(string, ...interface{}), group []difflib.OpCode) {
+ first, last := group[0], group[len(group)-1]
+ range1 := formatRangeUnified(first.I1, last.I2)
+ range2 := formatRangeUnified(first.J1, last.J2)
+ wf("@@ -%s +%s @@\n", range1, range2)
+}
+
+// Convert range to the "ed" format
+func formatRangeUnified(start, stop int) string {
+ // Per the diff spec at http://www.unix.org/single_unix_specification/
+ beginning := start + 1 // lines start numbering with one
+ length := stop - start
+ if length == 1 {
+ return fmt.Sprintf("%d", beginning)
+ }
+ if length == 0 {
+ beginning-- // empty ranges begin at line just before the range
+ }
+ return fmt.Sprintf("%d,%d", beginning, length)
+}
+
+func formatLines(writeLine func(string, string), prefix string, lines []string) {
+ for _, line := range lines {
+ writeLine(prefix, line)
+ }
+ // Add a newline if the last line is missing one so that the diff displays
+ // properly.
+ if !strings.HasSuffix(lines[len(lines)-1], "\n") {
+ writeLine("", "\n")
+ }
+}
@@ -0,0 +1,27 @@
+package format // import "gotest.tools/internal/format"
+
+import "fmt"
+
+// Message accepts a msgAndArgs varargs and formats it using fmt.Sprintf
+func Message(msgAndArgs ...interface{}) string {
+ switch len(msgAndArgs) {
+ case 0:
+ return ""
+ case 1:
+ return fmt.Sprintf("%v", msgAndArgs[0])
+ default:
+ return fmt.Sprintf(msgAndArgs[0].(string), msgAndArgs[1:]...)
+ }
+}
+
+// WithCustomMessage accepts one or two messages and formats them appropriately
+func WithCustomMessage(source string, msgAndArgs ...interface{}) string {
+ custom := Message(msgAndArgs...)
+ switch {
+ case custom == "":
+ return source
+ case source == "":
+ return custom
+ }
+ return fmt.Sprintf("%s: %s", source, custom)
+}
@@ -0,0 +1,163 @@
+package source // import "gotest.tools/internal/source"
+
+import (
+ "bytes"
+ "fmt"
+ "go/ast"
+ "go/format"
+ "go/parser"
+ "go/token"
+ "os"
+ "runtime"
+ "strconv"
+ "strings"
+
+ "github.com/pkg/errors"
+)
+
+const baseStackIndex = 1
+
+// FormattedCallExprArg returns the argument from an ast.CallExpr at the
+// index in the call stack. The argument is formatted using FormatNode.
+func FormattedCallExprArg(stackIndex int, argPos int) (string, error) {
+ args, err := CallExprArgs(stackIndex + 1)
+ if err != nil {
+ return "", err
+ }
+ return FormatNode(args[argPos])
+}
+
+func getNodeAtLine(filename string, lineNum int) (ast.Node, error) {
+ fileset := token.NewFileSet()
+ astFile, err := parser.ParseFile(fileset, filename, nil, parser.AllErrors)
+ if err != nil {
+ return nil, errors.Wrapf(err, "failed to parse source file: %s", filename)
+ }
+
+ node := scanToLine(fileset, astFile, lineNum)
+ if node == nil {
+ return nil, errors.Errorf(
+ "failed to find an expression on line %d in %s", lineNum, filename)
+ }
+ return node, nil
+}
+
+func scanToLine(fileset *token.FileSet, node ast.Node, lineNum int) ast.Node {
+ v := &scanToLineVisitor{lineNum: lineNum, fileset: fileset}
+ ast.Walk(v, node)
+ return v.matchedNode
+}
+
+type scanToLineVisitor struct {
+ lineNum int
+ matchedNode ast.Node
+ fileset *token.FileSet
+}
+
+func (v *scanToLineVisitor) Visit(node ast.Node) ast.Visitor {
+ if node == nil || v.matchedNode != nil {
+ return nil
+ }
+ if v.nodePosition(node).Line == v.lineNum {
+ v.matchedNode = node
+ return nil
+ }
+ return v
+}
+
+// In golang 1.9 the line number changed from being the line where the statement
+// ended to the line where the statement began.
+func (v *scanToLineVisitor) nodePosition(node ast.Node) token.Position {
+ if goVersionBefore19 {
+ return v.fileset.Position(node.End())
+ }
+ return v.fileset.Position(node.Pos())
+}
+
+var goVersionBefore19 = isGOVersionBefore19()
+
+func isGOVersionBefore19() bool {
+ version := runtime.Version()
+ // not a release version
+ if !strings.HasPrefix(version, "go") {
+ return false
+ }
+ version = strings.TrimPrefix(version, "go")
+ parts := strings.Split(version, ".")
+ if len(parts) < 2 {
+ return false
+ }
+ minor, err := strconv.ParseInt(parts[1], 10, 32)
+ return err == nil && parts[0] == "1" && minor < 9
+}
+
+func getCallExprArgs(node ast.Node) ([]ast.Expr, error) {
+ visitor := &callExprVisitor{}
+ ast.Walk(visitor, node)
+ if visitor.expr == nil {
+ return nil, errors.New("failed to find call expression")
+ }
+ return visitor.expr.Args, nil
+}
+
+type callExprVisitor struct {
+ expr *ast.CallExpr
+}
+
+func (v *callExprVisitor) Visit(node ast.Node) ast.Visitor {
+ if v.expr != nil || node == nil {
+ return nil
+ }
+ debug("visit (%T): %s", node, debugFormatNode{node})
+
+ if callExpr, ok := node.(*ast.CallExpr); ok {
+ v.expr = callExpr
+ return nil
+ }
+ return v
+}
+
+// FormatNode using go/format.Node and return the result as a string
+func FormatNode(node ast.Node) (string, error) {
+ buf := new(bytes.Buffer)
+ err := format.Node(buf, token.NewFileSet(), node)
+ return buf.String(), err
+}
+
+// CallExprArgs returns the ast.Expr slice for the args of an ast.CallExpr at
+// the index in the call stack.
+func CallExprArgs(stackIndex int) ([]ast.Expr, error) {
+ _, filename, lineNum, ok := runtime.Caller(baseStackIndex + stackIndex)
+ if !ok {
+ return nil, errors.New("failed to get call stack")
+ }
+ debug("call stack position: %s:%d", filename, lineNum)
+
+ node, err := getNodeAtLine(filename, lineNum)
+ if err != nil {
+ return nil, err
+ }
+ debug("found node (%T): %s", node, debugFormatNode{node})
+
+ return getCallExprArgs(node)
+}
+
+var debugEnabled = os.Getenv("GOTESTYOURSELF_DEBUG") != ""
+
+func debug(format string, args ...interface{}) {
+ if debugEnabled {
+ fmt.Fprintf(os.Stderr, "DEBUG: "+format+"\n", args...)
+ }
+}
+
+type debugFormatNode struct {
+ ast.Node
+}
+
+func (n debugFormatNode) String() string {
+ out, err := FormatNode(n.Node)
+ if err != nil {
+ return fmt.Sprintf("failed to format %s: %s", n.Node, err)
+ }
+ return out
+}