Daniel Banck created
With https://github.com/zed-industries/zed/pull/6882 basic syntax
highlighting support for Terraform has arrived in Zed. To fully support
all features of the language server (when it lands), it's necessary to
handle `*.tfvars` slightly differently.
TL;DR: [terraform-ls](https://github.com/hashicorp/terraform-ls) expects
`terraform` as language id for `*.tf` files and `terraform-vars` as
language id for `*.tfvars` files because the allowed configuration
inside the files is different. Duplicating the Terraform language
configuration was the only way I could see to achieve this.
---
In the
[LSP](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#textDocumentItem),
text documents have a language identifier to identify a document on the
server side to avoid reinterpreting the file extension.
The Terraform language server currently uses two different language
identifiers:
* `terraform` - for `*.tf` files
* `terraform-vars` - for `*.tfvars` files
Both file types contain HCL and can be highlighted using the same
grammar and tree-sitter configuration files. The difference in the file
content is that `*.tfvars` files only allow top-level attributes and no
blocks. [_So you could argue that `*.tfvars` can use a stripped down
version of the grammar_]. To set the right context (which affects
completion, hover, validation...) for each file, we need to send a
different language id.
The only way I could see to achieve this with the current architecture
was to copy the Terraform language configuration with a different `name`
and different `path_suffixes`. Everything else is the same.
A Terraform LSP adapter implementation would then map the language
configurations to their specific language ids:
```rust
fn language_ids(&self) -> HashMap<String, String> {
HashMap::from_iter([
("Terraform".into(), "terraform".into()),
("Terraform Vars".into(), "terraform-vars".into()),
])
}
```
I think it might be helpful in the future to have another way to map
file extensions to specific language ids without having to create a new
language configuration.
### UX Before
### UX After
Release Notes:
- N/A
---
* Part of https://github.com/zed-industries/zed/issues/5098crates/zed/src/languages.rs | 1
crates/zed/src/languages/terraform-vars/config.toml | 14 +
crates/zed/src/languages/terraform-vars/highlights.scm | 159 ++++++++++++
crates/zed/src/languages/terraform-vars/indents.scm | 14 +
crates/zed/src/languages/terraform-vars/injections.scm | 9
crates/zed/src/languages/terraform/config.toml | 2
6 files changed, 198 insertions(+), 1 deletion(-)
@@ -287,6 +287,7 @@ pub fn init(
language("uiua", vec![Arc::new(uiua::UiuaLanguageServer {})]);
language("proto", vec![]);
language("terraform", vec![]);
+ language("terraform-vars", vec![]);
language("hcl", vec![]);
}
@@ -0,0 +1,14 @@
+name = "Terraform Vars"
+grammar = "hcl"
+path_suffixes = ["tfvars"]
+line_comments = ["# ", "// "]
+block_comment = ["/*", "*/"]
+autoclose_before = ",}])"
+brackets = [
+ { start = "{", end = "}", close = true, newline = true },
+ { start = "[", end = "]", close = true, newline = true },
+ { start = "(", end = ")", close = true, newline = true },
+ { start = "\"", end = "\"", close = true, newline = false, not_in = ["comment", "string"] },
+ { start = "'", end = "'", close = true, newline = false, not_in = ["comment", "string"] },
+ { start = "/*", end = " */", close = true, newline = false, not_in = ["comment", "string"] },
+]
@@ -0,0 +1,159 @@
+; https://github.com/nvim-treesitter/nvim-treesitter/blob/cb79d2446196d25607eb1d982c96939abdf67b8e/queries/hcl/highlights.scm
+; highlights.scm
+[
+ "!"
+ "\*"
+ "/"
+ "%"
+ "\+"
+ "-"
+ ">"
+ ">="
+ "<"
+ "<="
+ "=="
+ "!="
+ "&&"
+ "||"
+] @operator
+
+[
+ "{"
+ "}"
+ "["
+ "]"
+ "("
+ ")"
+] @punctuation.bracket
+
+[
+ "."
+ ".*"
+ ","
+ "[*]"
+] @punctuation.delimiter
+
+[
+ (ellipsis)
+ "\?"
+ "=>"
+] @punctuation.special
+
+[
+ ":"
+ "="
+] @punctuation
+
+[
+ "for"
+ "endfor"
+ "in"
+ "if"
+ "else"
+ "endif"
+] @keyword
+
+[
+ (quoted_template_start) ; "
+ (quoted_template_end) ; "
+ (template_literal) ; non-interpolation/directive content
+] @string
+
+[
+ (heredoc_identifier) ; END
+ (heredoc_start) ; << or <<-
+] @punctuation.delimiter
+
+[
+ (template_interpolation_start) ; ${
+ (template_interpolation_end) ; }
+ (template_directive_start) ; %{
+ (template_directive_end) ; }
+ (strip_marker) ; ~
+] @punctuation.special
+
+(numeric_lit) @number
+
+(bool_lit) @boolean
+
+(null_lit) @constant
+
+(comment) @comment
+
+(identifier) @variable
+
+(body
+ (block
+ (identifier) @keyword))
+
+(body
+ (block
+ (body
+ (block
+ (identifier) @type))))
+
+(function_call
+ (identifier) @function)
+
+(attribute
+ (identifier) @variable)
+
+; { key: val }
+;
+; highlight identifier keys as though they were block attributes
+(object_elem
+ key:
+ (expression
+ (variable_expr
+ (identifier) @variable)))
+
+; var.foo, data.bar
+;
+; first element in get_attr is a variable.builtin or a reference to a variable.builtin
+(expression
+ (variable_expr
+ (identifier) @variable)
+ (get_attr
+ (identifier) @variable))
+
+; https://github.com/nvim-treesitter/nvim-treesitter/blob/cb79d2446196d25607eb1d982c96939abdf67b8e/queries/terraform/highlights.scm
+; Terraform specific references
+;
+;
+; local/module/data/var/output
+(expression
+ (variable_expr
+ (identifier) @variable
+ (#any-of? @variable "data" "var" "local" "module" "output"))
+ (get_attr
+ (identifier) @variable))
+
+; path.root/cwd/module
+(expression
+ (variable_expr
+ (identifier) @type
+ (#eq? @type "path"))
+ (get_attr
+ (identifier) @variable
+ (#any-of? @variable "root" "cwd" "module")))
+
+; terraform.workspace
+(expression
+ (variable_expr
+ (identifier) @type
+ (#eq? @type "terraform"))
+ (get_attr
+ (identifier) @variable
+ (#any-of? @variable "workspace")))
+
+; Terraform specific keywords
+; FIXME: ideally only for identifiers under a `variable` block to minimize false positives
+((identifier) @type
+ (#any-of? @type "bool" "string" "number" "object" "tuple" "list" "map" "set" "any"))
+
+(object_elem
+ val:
+ (expression
+ (variable_expr
+ (identifier) @type
+ (#any-of? @type "bool" "string" "number" "object" "tuple" "list" "map" "set" "any"))))
@@ -0,0 +1,14 @@
+; https://github.com/nvim-treesitter/nvim-treesitter/blob/ce4adf11cfe36fc5b0e5bcdce0c7c6e8fbc9798a/queries/hcl/indents.scm
+[
+ (block)
+ (object)
+ (tuple)
+ (function_call)
+] @indent
+
+(_ "[" "]" @end) @indent
+(_ "(" ")" @end) @indent
+(_ "{" "}" @end) @indent
+
+; https://github.com/nvim-treesitter/nvim-treesitter/blob/ce4adf11cfe36fc5b0e5bcdce0c7c6e8fbc9798a/queries/terraform/indents.scm
+; inherits: hcl
@@ -0,0 +1,9 @@
+; https://github.com/nvim-treesitter/nvim-treesitter/blob/ce4adf11cfe36fc5b0e5bcdce0c7c6e8fbc9798a/queries/hcl/injections.scm
+
+(heredoc_template
+ (template_literal) @content
+ (heredoc_identifier) @language
+ (#downcase! @language))
+
+; https://github.com/nvim-treesitter/nvim-treesitter/blob/ce4adf11cfe36fc5b0e5bcdce0c7c6e8fbc9798a/queries/terraform/injections.scm
+; inherits: hcl
@@ -1,6 +1,6 @@
name = "Terraform"
grammar = "hcl"
-path_suffixes = ["tf", "tfvars"]
+path_suffixes = ["tf"]
line_comments = ["# ", "// "]
block_comment = ["/*", "*/"]
autoclose_before = ",}])"