anchor.rs

  1use crate::MultiBufferPoint;
  2
  3use super::{ExcerptId, MultiBufferSnapshot, ToOffset, ToPoint};
  4use language::{OffsetUtf16, Point, TextDimension};
  5use std::{
  6    cmp::Ordering,
  7    ops::{Range, Sub},
  8};
  9use sum_tree::Bias;
 10use text::BufferId;
 11
 12#[derive(Clone, Copy, Eq, PartialEq, Debug, Hash)]
 13pub struct Anchor {
 14    pub buffer_id: Option<BufferId>,
 15    pub excerpt_id: ExcerptId,
 16    pub text_anchor: text::Anchor,
 17    /// Some if this anchor points to within a deleted diff hunk.
 18    pub diff_base_anchor: Option<text::Anchor>,
 19}
 20
 21impl Anchor {
 22    pub fn with_diff_base_anchor(self, diff_base_anchor: text::Anchor) -> Self {
 23        Self {
 24            diff_base_anchor: Some(diff_base_anchor),
 25            ..self
 26        }
 27    }
 28
 29    pub fn in_buffer(
 30        excerpt_id: ExcerptId,
 31        buffer_id: BufferId,
 32        text_anchor: text::Anchor,
 33    ) -> Self {
 34        Self {
 35            buffer_id: Some(buffer_id),
 36            excerpt_id,
 37            text_anchor,
 38            diff_base_anchor: None,
 39        }
 40    }
 41
 42    pub fn range_in_buffer(
 43        excerpt_id: ExcerptId,
 44        buffer_id: BufferId,
 45        range: Range<text::Anchor>,
 46    ) -> Range<Self> {
 47        Self::in_buffer(excerpt_id, buffer_id, range.start)
 48            ..Self::in_buffer(excerpt_id, buffer_id, range.end)
 49    }
 50
 51    pub fn min() -> Self {
 52        Self {
 53            buffer_id: None,
 54            excerpt_id: ExcerptId::min(),
 55            text_anchor: text::Anchor::MIN,
 56            diff_base_anchor: None,
 57        }
 58    }
 59
 60    pub fn max() -> Self {
 61        Self {
 62            buffer_id: None,
 63            excerpt_id: ExcerptId::max(),
 64            text_anchor: text::Anchor::MAX,
 65            diff_base_anchor: None,
 66        }
 67    }
 68
 69    pub fn cmp(&self, other: &Anchor, snapshot: &MultiBufferSnapshot) -> Ordering {
 70        if self == other {
 71            return Ordering::Equal;
 72        }
 73
 74        let self_excerpt_id = snapshot.latest_excerpt_id(self.excerpt_id);
 75        let other_excerpt_id = snapshot.latest_excerpt_id(other.excerpt_id);
 76
 77        let excerpt_id_cmp = self_excerpt_id.cmp(&other_excerpt_id, snapshot);
 78        if excerpt_id_cmp.is_ne() {
 79            return excerpt_id_cmp;
 80        }
 81        if self_excerpt_id == ExcerptId::min() || self_excerpt_id == ExcerptId::max() {
 82            return Ordering::Equal;
 83        }
 84        if let Some(excerpt) = snapshot.excerpt(self_excerpt_id) {
 85            let text_cmp = self.text_anchor.cmp(&other.text_anchor, &excerpt.buffer);
 86            if text_cmp.is_ne() {
 87                return text_cmp;
 88            }
 89            if (self.diff_base_anchor.is_some() || other.diff_base_anchor.is_some())
 90                && let Some(base_text) = snapshot
 91                    .diffs
 92                    .get(&excerpt.buffer_id)
 93                    .map(|diff| diff.base_text())
 94            {
 95                let self_anchor = self.diff_base_anchor.filter(|a| base_text.can_resolve(a));
 96                let other_anchor = other.diff_base_anchor.filter(|a| base_text.can_resolve(a));
 97                return match (self_anchor, other_anchor) {
 98                    (Some(a), Some(b)) => a.cmp(&b, base_text),
 99                    (Some(_), None) => match other.text_anchor.bias {
100                        Bias::Left => Ordering::Greater,
101                        Bias::Right => Ordering::Less,
102                    },
103                    (None, Some(_)) => match self.text_anchor.bias {
104                        Bias::Left => Ordering::Less,
105                        Bias::Right => Ordering::Greater,
106                    },
107                    (None, None) => Ordering::Equal,
108                };
109            }
110        }
111        Ordering::Equal
112    }
113
114    pub fn bias(&self) -> Bias {
115        self.text_anchor.bias
116    }
117
118    pub fn bias_left(&self, snapshot: &MultiBufferSnapshot) -> Anchor {
119        if self.text_anchor.bias != Bias::Left
120            && let Some(excerpt) = snapshot.excerpt(self.excerpt_id)
121        {
122            return Self {
123                buffer_id: self.buffer_id,
124                excerpt_id: self.excerpt_id,
125                text_anchor: self.text_anchor.bias_left(&excerpt.buffer),
126                diff_base_anchor: self.diff_base_anchor.map(|a| {
127                    if let Some(base_text) = snapshot
128                        .diffs
129                        .get(&excerpt.buffer_id)
130                        .map(|diff| diff.base_text())
131                        && a.buffer_id == Some(base_text.remote_id())
132                    {
133                        return a.bias_left(base_text);
134                    }
135                    a
136                }),
137            };
138        }
139        *self
140    }
141
142    pub fn bias_right(&self, snapshot: &MultiBufferSnapshot) -> Anchor {
143        if self.text_anchor.bias != Bias::Right
144            && let Some(excerpt) = snapshot.excerpt(self.excerpt_id)
145        {
146            return Self {
147                buffer_id: self.buffer_id,
148                excerpt_id: self.excerpt_id,
149                text_anchor: self.text_anchor.bias_right(&excerpt.buffer),
150                diff_base_anchor: self.diff_base_anchor.map(|a| {
151                    if let Some(base_text) = snapshot
152                        .diffs
153                        .get(&excerpt.buffer_id)
154                        .map(|diff| diff.base_text())
155                        && a.buffer_id == Some(base_text.remote_id())
156                    {
157                        return a.bias_right(base_text);
158                    }
159                    a
160                }),
161            };
162        }
163        *self
164    }
165
166    pub fn is_valid(&self, snapshot: &MultiBufferSnapshot) -> bool {
167        if *self == Anchor::min() || *self == Anchor::max() {
168            true
169        } else if let Some(excerpt) = snapshot.excerpt(self.excerpt_id) {
170            (self.text_anchor == excerpt.range.context.start
171                || self.text_anchor == excerpt.range.context.end
172                || self.text_anchor.is_valid(&excerpt.buffer))
173                && excerpt.contains(self)
174        } else {
175            false
176        }
177    }
178}
179
180impl ToOffset for Anchor {
181    fn to_offset(&self, snapshot: &MultiBufferSnapshot) -> usize {
182        snapshot.summary_for_anchor(self)
183    }
184    fn to_offset_utf16(&self, snapshot: &MultiBufferSnapshot) -> OffsetUtf16 {
185        snapshot.summary_for_anchor(self)
186    }
187}
188
189impl ToPoint for Anchor {
190    fn to_point<'a>(&self, snapshot: &MultiBufferSnapshot) -> MultiBufferPoint {
191        snapshot.summary_for_anchor(self)
192    }
193    fn to_point_utf16(&self, snapshot: &MultiBufferSnapshot) -> rope::PointUtf16 {
194        snapshot.summary_for_anchor(self)
195    }
196}
197
198pub trait AnchorRangeExt {
199    fn cmp(&self, other: &Range<Anchor>, buffer: &MultiBufferSnapshot) -> Ordering;
200    fn includes(&self, other: &Range<Anchor>, buffer: &MultiBufferSnapshot) -> bool;
201    fn overlaps(&self, other: &Range<Anchor>, buffer: &MultiBufferSnapshot) -> bool;
202    fn to_offset(&self, content: &MultiBufferSnapshot) -> Range<usize>;
203    fn to_point(&self, content: &MultiBufferSnapshot) -> Range<MultiBufferPoint>;
204}
205
206impl AnchorRangeExt for Range<Anchor> {
207    fn cmp(&self, other: &Range<Anchor>, buffer: &MultiBufferSnapshot) -> Ordering {
208        match self.start.cmp(&other.start, buffer) {
209            Ordering::Equal => other.end.cmp(&self.end, buffer),
210            ord => ord,
211        }
212    }
213
214    fn includes(&self, other: &Range<Anchor>, buffer: &MultiBufferSnapshot) -> bool {
215        self.start.cmp(&other.start, buffer).is_le() && other.end.cmp(&self.end, buffer).is_le()
216    }
217
218    fn overlaps(&self, other: &Range<Anchor>, buffer: &MultiBufferSnapshot) -> bool {
219        self.end.cmp(&other.start, buffer).is_ge() && self.start.cmp(&other.end, buffer).is_le()
220    }
221
222    fn to_offset(&self, content: &MultiBufferSnapshot) -> Range<usize> {
223        self.start.to_offset(content)..self.end.to_offset(content)
224    }
225
226    fn to_point(&self, content: &MultiBufferSnapshot) -> Range<MultiBufferPoint> {
227        self.start.to_point(content)..self.end.to_point(content)
228    }
229}
230
231#[derive(Clone, Copy, Eq, PartialEq, Debug, Hash, Ord, PartialOrd)]
232pub struct Offset(pub usize);