diffler_core/
session.rs

1//! Review session: comments and per-file viewed marks, reconciled against
2//! fresh diff models. Persistence lives in `store`.
3
4use std::collections::BTreeMap;
5use std::time::{SystemTime, UNIX_EPOCH};
6
7use serde::{Deserialize, Serialize};
8
9use crate::model::DiffModel;
10
11#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
12#[serde(rename_all = "snake_case")]
13pub enum CommentStatus {
14    Open,
15    Replied,
16    Resolved,
17}
18
19#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
20pub struct Reply {
21    pub author: String,
22    pub body: String,
23    pub at: u64,
24}
25
26/// Where a comment is anchored. `line` (and `line_end` for visual ranges)
27/// is the new-side line number unless the line is a deletion, then it is
28/// the old-side number with `on_old_side`.
29#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
30pub struct Anchor {
31    pub file: String,
32    #[serde(default)]
33    pub line: Option<u32>,
34    #[serde(default)]
35    pub line_end: Option<u32>,
36    #[serde(default)]
37    pub on_old_side: bool,
38    /// Snapshot of the anchored line's text, so the UI can mark the
39    /// comment outdated when the agent rewrites the line.
40    #[serde(default)]
41    pub line_text: Option<String>,
42}
43
44impl Anchor {
45    /// Whether the anchor no longer matches the model. Range comments
46    /// anchor to their end line: that is the line whose disappearance or
47    /// `line_text` drift marks them outdated. A line-less anchor is
48    /// outdated only once the whole file leaves the diff.
49    pub fn is_outdated(&self, model: &DiffModel) -> bool {
50        match self.line_end.or(self.line) {
51            Some(line) => match model.find_line(&self.file, line, self.on_old_side) {
52                Some(found) => self
53                    .line_text
54                    .as_deref()
55                    .is_some_and(|snap| snap != found.text),
56                None => true,
57            },
58            None => !model.files.iter().any(|f| f.path == self.file),
59        }
60    }
61}
62
63#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
64pub struct Comment {
65    pub id: String,
66    pub author: String,
67    pub anchor: Anchor,
68    pub body: String,
69    pub status: CommentStatus,
70    #[serde(default)]
71    pub replies: Vec<Reply>,
72    pub at: u64,
73}
74
75#[derive(Debug, Clone, Default, PartialEq, Eq, Serialize, Deserialize)]
76pub struct Session {
77    #[serde(default)]
78    pub comments: Vec<Comment>,
79    /// Per-file viewed marks: path -> content hash of the new side at the
80    /// time of marking. A changed hash means the file needs re-review.
81    #[serde(default)]
82    pub viewed: BTreeMap<String, String>,
83}
84
85pub fn now_unix() -> u64 {
86    SystemTime::now()
87        .duration_since(UNIX_EPOCH)
88        .map_or(0, |d| d.as_secs())
89}
90
91impl Session {
92    pub fn add_comment(&mut self, author: &str, anchor: Anchor, body: &str) -> &Comment {
93        self.comments.push(Comment {
94            id: uuid::Uuid::new_v4().to_string(),
95            author: author.to_owned(),
96            anchor,
97            body: body.to_owned(),
98            status: CommentStatus::Open,
99            replies: Vec::new(),
100            at: now_unix(),
101        });
102        // just pushed, so the vec is non-empty
103        #[allow(clippy::expect_used)]
104        self.comments.last().expect("just pushed")
105    }
106
107    fn comment_mut(&mut self, comment_id: &str) -> Option<&mut Comment> {
108        self.comments.iter_mut().find(|c| c.id == comment_id)
109    }
110
111    pub fn reply(&mut self, comment_id: &str, author: &str, body: &str) -> bool {
112        let Some(comment) = self.comment_mut(comment_id) else {
113            return false;
114        };
115        comment.replies.push(Reply {
116            author: author.to_owned(),
117            body: body.to_owned(),
118            at: now_unix(),
119        });
120        if comment.status == CommentStatus::Open {
121            comment.status = CommentStatus::Replied;
122        }
123        true
124    }
125
126    pub fn resolve(&mut self, comment_id: &str) -> bool {
127        let Some(comment) = self.comment_mut(comment_id) else {
128            return false;
129        };
130        comment.status = CommentStatus::Resolved;
131        true
132    }
133
134    /// Replace a comment's body in place (status, replies, and anchor are kept).
135    pub fn edit_comment(&mut self, comment_id: &str, body: &str) -> bool {
136        let Some(comment) = self.comment_mut(comment_id) else {
137            return false;
138        };
139        body.clone_into(&mut comment.body);
140        true
141    }
142
143    pub fn mark_viewed(&mut self, path: &str, hash: &str) {
144        self.viewed.insert(path.to_owned(), hash.to_owned());
145    }
146
147    pub fn unmark_viewed(&mut self, path: &str) {
148        self.viewed.remove(path);
149    }
150
151    /// A stale hash means the file changed since it was marked: not viewed
152    /// anymore (auto-reset semantics).
153    pub fn is_viewed(&self, path: &str, current_hash: &str) -> bool {
154        self.viewed.get(path).is_some_and(|h| h == current_hash)
155    }
156
157    /// Drop viewed marks for files that left the diff or whose content
158    /// changed since marking. Comments are kept: they stay useful (possibly
159    /// flagged outdated) even when their file moves on.
160    pub fn reconcile(&mut self, model: &DiffModel) {
161        let live: BTreeMap<&str, String> = model
162            .files
163            .iter()
164            .map(|f| (f.path.as_str(), f.content_hash()))
165            .collect();
166        self.viewed
167            .retain(|path, hash| live.get(path.as_str()).is_some_and(|h| h == hash));
168    }
169}
170
171#[cfg(test)]
172mod tests {
173    use crate::model::{DiffLine, FileDiff, FileStatus, Hunk, HunkId, LineKind};
174
175    use super::*;
176
177    fn anchor(file: &str) -> Anchor {
178        Anchor {
179            file: file.to_owned(),
180            line: Some(3),
181            line_end: None,
182            on_old_side: false,
183            line_text: None,
184        }
185    }
186
187    fn file_diff(path: &str, new_text: &str) -> FileDiff {
188        FileDiff {
189            path: path.to_owned(),
190            old_path: None,
191            status: FileStatus::Modified,
192            binary: false,
193            old_text: None,
194            new_text: Some(new_text.to_owned()),
195            hunks: vec![],
196        }
197    }
198
199    fn model(files: Vec<FileDiff>) -> DiffModel {
200        DiffModel { files }
201    }
202
203    #[test]
204    fn comment_lifecycle_open_replied_resolved() {
205        let mut s = Session::default();
206        let id = s.add_comment("mattf", anchor("a.txt"), "why?").id.clone();
207        assert_eq!(s.comments[0].status, CommentStatus::Open);
208        assert!(s.reply(&id, "agent", "because"));
209        assert_eq!(s.comments[0].status, CommentStatus::Replied);
210        assert!(s.resolve(&id));
211        assert_eq!(s.comments[0].status, CommentStatus::Resolved);
212        assert!(
213            s.comments
214                .iter()
215                .all(|c| c.status == CommentStatus::Resolved)
216        );
217    }
218
219    #[test]
220    fn reply_to_missing_comment_returns_false() {
221        let mut s = Session::default();
222        assert!(!s.reply("nope", "agent", "hi"));
223    }
224
225    #[test]
226    fn resolve_missing_comment_returns_false() {
227        let mut s = Session::default();
228        assert!(!s.resolve("nope"));
229    }
230
231    #[test]
232    fn edit_comment_replaces_body_and_keeps_status() {
233        let mut s = Session::default();
234        let id = s
235            .add_comment("mattf", anchor("a.txt"), "old body")
236            .id
237            .clone();
238        assert!(s.reply(&id, "agent", "ack"));
239        assert!(s.edit_comment(&id, "new body"));
240        let c = s.comments.iter().find(|c| c.id == id).expect("comment");
241        assert_eq!(c.body, "new body");
242        assert_eq!(c.status, CommentStatus::Replied, "status is untouched");
243        assert_eq!(c.replies.len(), 1, "replies are untouched");
244        assert!(!s.edit_comment("nope", "x"));
245    }
246
247    #[test]
248    fn unresolved_comments_filters_resolved_only() {
249        let mut s = Session::default();
250        let keep = s.add_comment("mattf", anchor("a.txt"), "open").id.clone();
251        let done = s.add_comment("mattf", anchor("a.txt"), "done").id.clone();
252        assert!(s.resolve(&done));
253        let unresolved: Vec<_> = s
254            .comments
255            .iter()
256            .filter(|c| c.status != CommentStatus::Resolved)
257            .map(|c| c.id.clone())
258            .collect();
259        assert_eq!(unresolved, vec![keep]);
260    }
261
262    #[test]
263    fn session_serializes_round_trip_with_range_anchor() {
264        let mut s = Session::default();
265        let mut range = anchor("a.txt");
266        range.line = Some(3);
267        range.line_end = Some(7);
268        s.add_comment("mattf", range, "this whole block");
269        s.mark_viewed("b.txt", "hash-b");
270        let json = serde_json::to_string(&s).expect("serialize");
271        let back: Session = serde_json::from_str(&json).expect("deserialize");
272        assert_eq!(s, back);
273        assert_eq!(back.comments[0].anchor.line_end, Some(7));
274    }
275
276    #[test]
277    fn is_viewed_true_for_same_hash_false_after_change() {
278        let mut s = Session::default();
279        s.mark_viewed("a.txt", "hash-1");
280        assert!(s.is_viewed("a.txt", "hash-1"));
281        assert!(!s.is_viewed("a.txt", "hash-2"));
282        assert!(!s.is_viewed("other.txt", "hash-1"));
283    }
284
285    #[test]
286    fn unmark_viewed_removes_entry() {
287        let mut s = Session::default();
288        s.mark_viewed("a.txt", "hash-1");
289        s.unmark_viewed("a.txt");
290        assert!(!s.is_viewed("a.txt", "hash-1"));
291    }
292
293    /// One file, one hunk: context(1/1), deleted(2), added(2), context(3/3).
294    fn hunked_model() -> DiffModel {
295        DiffModel {
296            files: vec![FileDiff {
297                path: "src/auth.py".into(),
298                old_path: None,
299                status: FileStatus::Modified,
300                binary: false,
301                old_text: None,
302                new_text: None,
303                hunks: vec![Hunk {
304                    id: HunkId("h1".into()),
305                    old_start: 1,
306                    old_lines: 3,
307                    new_start: 1,
308                    new_lines: 3,
309                    context: String::new(),
310                    lines: vec![
311                        DiffLine::new(LineKind::Context, Some(1), Some(1), "one".into()),
312                        DiffLine::new(LineKind::Deleted, Some(2), None, "two".into()),
313                        DiffLine::new(LineKind::Added, None, Some(2), "TWO".into()),
314                        DiffLine::new(LineKind::Context, Some(3), Some(3), "three".into()),
315                    ],
316                }],
317            }],
318        }
319    }
320
321    fn line_anchor(file: &str, line: Option<u32>) -> Anchor {
322        Anchor {
323            file: file.to_owned(),
324            line,
325            line_end: None,
326            on_old_side: false,
327            line_text: None,
328        }
329    }
330
331    #[test]
332    fn anchor_with_matching_line_text_is_current() {
333        let mut a = line_anchor("src/auth.py", Some(2));
334        a.line_text = Some("TWO".to_owned());
335        assert!(!a.is_outdated(&hunked_model()));
336        // without a snapshot, a present line counts as current
337        a.line_text = None;
338        assert!(!a.is_outdated(&hunked_model()));
339    }
340
341    #[test]
342    fn anchor_with_drifted_line_text_is_outdated() {
343        let mut a = line_anchor("src/auth.py", Some(2));
344        a.line_text = Some("old text".to_owned());
345        assert!(a.is_outdated(&hunked_model()));
346    }
347
348    #[test]
349    fn anchor_to_a_departed_line_is_outdated() {
350        let a = line_anchor("src/auth.py", Some(99));
351        assert!(a.is_outdated(&hunked_model()));
352    }
353
354    #[test]
355    fn old_side_anchor_checks_the_old_line() {
356        let mut a = line_anchor("src/auth.py", Some(2));
357        a.on_old_side = true;
358        a.line_text = Some("two".to_owned());
359        assert!(!a.is_outdated(&hunked_model()));
360        a.line_text = Some("TWO".to_owned());
361        assert!(a.is_outdated(&hunked_model()), "old side carries 'two'");
362    }
363
364    #[test]
365    fn range_anchor_judges_drift_on_its_end_line() {
366        let mut a = line_anchor("src/auth.py", Some(1));
367        a.line_end = Some(3);
368        a.line_text = Some("three".to_owned());
369        assert!(!a.is_outdated(&hunked_model()), "end line still matches");
370        a.line_text = Some("changed".to_owned());
371        assert!(a.is_outdated(&hunked_model()), "end line drifted");
372    }
373
374    #[test]
375    fn file_level_anchor_is_outdated_only_when_the_file_departs() {
376        assert!(!line_anchor("src/auth.py", None).is_outdated(&hunked_model()));
377        assert!(line_anchor("gone.py", None).is_outdated(&hunked_model()));
378    }
379
380    #[test]
381    fn reconcile_drops_departed_and_changed_keeps_matching() {
382        let kept = file_diff("kept.txt", "stable content\n");
383        let changed = file_diff("changed.txt", "rewritten content\n");
384
385        let mut s = Session::default();
386        s.mark_viewed("kept.txt", &kept.content_hash());
387        s.mark_viewed("changed.txt", "hash-of-old-content");
388        s.mark_viewed("departed.txt", "whatever");
389        s.add_comment("mattf", anchor("departed.txt"), "still relevant");
390
391        s.reconcile(&model(vec![kept, changed]));
392
393        assert!(s.viewed.contains_key("kept.txt"));
394        assert!(!s.viewed.contains_key("changed.txt"));
395        assert!(!s.viewed.contains_key("departed.txt"));
396        // comments survive reconciliation untouched
397        assert_eq!(s.comments.len(), 1);
398    }
399}
diffler_core/session.rs

diffler_core/
session.rs
