feat(app): better diff/code comments (#14621)

Co-authored-by: adamelmore <[email protected]>
Co-authored-by: David Hill <[email protected]>

6 files changed, 147 insertions, 3 deletions

diff --git a/packages/app/src/context/comments.test.ts b/packages/app/src/context/comments.test.ts
index bee5c7871..82fa170f2 100644
--- a/packages/app/src/context/comments.test.ts
+++ b/packages/app/src/context/comments.test.ts
@@ -150,4 +150,37 @@ describe("comments session indexing", () => {
       dispose()
     })
   })
+
+  test("update changes only the targeted comment body", () => {
+    createRoot((dispose) => {
+      const comments = createCommentSessionForTest({
+        "a.ts": [line("a.ts", "a1", 10), line("a.ts", "a2", 20)],
+      })
+
+      comments.update("a.ts", "a2", "edited")
+
+      expect(comments.list("a.ts").map((item) => item.comment)).toEqual(["a1", "edited"])
+
+      dispose()
+    })
+  })
+
+  test("replace swaps comment state and clears focus state", () => {
+    createRoot((dispose) => {
+      const comments = createCommentSessionForTest({
+        "a.ts": [line("a.ts", "a1", 10)],
+      })
+
+      comments.setFocus({ file: "a.ts", id: "a1" })
+      comments.setActive({ file: "a.ts", id: "a1" })
+      comments.replace([line("b.ts", "b1", 30)])
+
+      expect(comments.list("a.ts")).toEqual([])
+      expect(comments.list("b.ts").map((item) => item.id)).toEqual(["b1"])
+      expect(comments.focus()).toBeNull()
+      expect(comments.active()).toBeNull()
+
+      dispose()
+    })
+  })
 })
diff --git a/packages/app/src/context/comments.tsx b/packages/app/src/context/comments.tsx
index ecf63e45b..a97010c0a 100644
--- a/packages/app/src/context/comments.tsx
+++ b/packages/app/src/context/comments.tsx
@@ -44,6 +44,37 @@ function aggregate(comments: Record<string, LineComment[]>) {
     .sort((a, b) => a.time - b.time)
 }
 
+function cloneSelection(selection: SelectedLineRange): SelectedLineRange {
+  const next: SelectedLineRange = {
+    start: selection.start,
+    end: selection.end,
+  }
+
+  if (selection.side) next.side = selection.side
+  if (selection.endSide) next.endSide = selection.endSide
+  return next
+}
+
+function cloneComment(comment: LineComment): LineComment {
+  return {
+    ...comment,
+    selection: cloneSelection(comment.selection),
+  }
+}
+
+function group(comments: LineComment[]) {
+  return comments.reduce<Record<string, LineComment[]>>((acc, comment) => {
+    const list = acc[comment.file]
+    const next = cloneComment(comment)
+    if (list) {
+      list.push(next)
+      return acc
+    }
+    acc[comment.file] = [next]
+    return acc
+  }, {})
+}
+
 function createCommentSessionState(store: Store<CommentStore>, setStore: SetStoreFunction<CommentStore>) {
   const [state, setState] = createStore({
     focus: null as CommentFocus | null,
@@ -70,6 +101,7 @@ function createCommentSessionState(store: Store<CommentStore>, setStore: SetStor
       id: uuid(),
       time: Date.now(),
       ...input,
+      selection: cloneSelection(input.selection),
     }
 
     batch(() => {
@@ -87,6 +119,23 @@ function createCommentSessionState(store: Store<CommentStore>, setStore: SetStor
     })
   }
 
+  const update = (file: string, id: string, comment: string) => {
+    setStore("comments", file, (items) =>
+      (items ?? []).map((item) => {
+        if (item.id !== id) return item
+        return { ...item, comment }
+      }),
+    )
+  }
+
+  const replace = (comments: LineComment[]) => {
+    batch(() => {
+      setStore("comments", reconcile(group(comments)))
+      setFocus(null)
+      setActive(null)
+    })
+  }
+
   const clear = () => {
     batch(() => {
       setStore("comments", reconcile({}))
@@ -100,6 +149,8 @@ function createCommentSessionState(store: Store<CommentStore>, setStore: SetStor
     all,
     add,
     remove,
+    update,
+    replace,
     clear,
     focus: () => state.focus,
     setFocus,
@@ -132,6 +183,8 @@ function createCommentSession(dir: string, id: string | undefined) {
     all: session.all,
     add: session.add,
     remove: session.remove,
+    update: session.update,
+    replace: session.replace,
     clear: session.clear,
     focus: session.focus,
     setFocus: session.setFocus,
@@ -176,6 +229,8 @@ export const { use: useComments, provider: CommentsProvider } = createSimpleCont
       all: () => session().all(),
       add: (input: Omit<LineComment, "id" | "time">) => session().add(input),
       remove: (file: string, id: string) => session().remove(file, id),
+      update: (file: string, id: string, comment: string) => session().update(file, id, comment),
+      replace: (comments: LineComment[]) => session().replace(comments),
       clear: () => session().clear(),
       focus: () => session().focus(),
       setFocus: (focus: CommentFocus | null) => session().setFocus(focus),
diff --git a/packages/app/src/context/file/view-cache.ts b/packages/app/src/context/file/view-cache.ts
index 6e8ddf62d..4c060174a 100644
--- a/packages/app/src/context/file/view-cache.ts
+++ b/packages/app/src/context/file/view-cache.ts
@@ -9,7 +9,7 @@ const MAX_FILE_VIEW_SESSIONS = 20
 const MAX_VIEW_FILES = 500
 
 function normalizeSelectedLines(range: SelectedLineRange): SelectedLineRange {
-  if (range.start <= range.end) return range
+  if (range.start <= range.end) return { ...range }
 
   const startSide = range.side
   const endSide = range.endSide ?? startSide
diff --git a/packages/app/src/context/layout-scroll.test.ts b/packages/app/src/context/layout-scroll.test.ts
index 2a13e4020..483be150f 100644
--- a/packages/app/src/context/layout-scroll.test.ts
+++ b/packages/app/src/context/layout-scroll.test.ts
@@ -41,4 +41,24 @@ describe("createScrollPersistence", () => {
       vi.useRealTimers()
     }
   })
+
+  test("reseeds empty cache after persisted snapshot loads", () => {
+    const snapshot = {
+      session: {},
+    } as Record<string, Record<string, { x: number; y: number }>>
+
+    const scroll = createScrollPersistence({
+      getSnapshot: (sessionKey) => snapshot[sessionKey],
+      onFlush: () => {},
+    })
+
+    expect(scroll.scroll("session", "review")).toBeUndefined()
+
+    snapshot.session = {
+      review: { x: 12, y: 34 },
+    }
+
+    expect(scroll.scroll("session", "review")).toEqual({ x: 12, y: 34 })
+    scroll.dispose()
+  })
 })
diff --git a/packages/app/src/context/layout-scroll.ts b/packages/app/src/context/layout-scroll.ts
index 30b0f6904..ef66eccd9 100644
--- a/packages/app/src/context/layout-scroll.ts
+++ b/packages/app/src/context/layout-scroll.ts
@@ -33,8 +33,16 @@ export function createScrollPersistence(opts: Options) {
   }
 
   function seed(sessionKey: string) {
-    if (cache[sessionKey]) return
-    setCache(sessionKey, clone(opts.getSnapshot(sessionKey)))
+    const next = clone(opts.getSnapshot(sessionKey))
+    const current = cache[sessionKey]
+    if (!current) {
+      setCache(sessionKey, next)
+      return
+    }
+
+    if (Object.keys(current).length > 0) return
+    if (Object.keys(next).length === 0) return
+    setCache(sessionKey, next)
   }
 
   function scroll(sessionKey: string, tab: string) {
diff --git a/packages/app/src/context/prompt.tsx b/packages/app/src/context/prompt.tsx
index 064892105..fb8226559 100644
--- a/packages/app/src/context/prompt.tsx
+++ b/packages/app/src/context/prompt.tsx
@@ -116,6 +116,10 @@ function contextItemKey(item: ContextItem) {
   return `${key}:c=${digest.slice(0, 8)}`
 }
 
+function isCommentItem(item: ContextItem | (ContextItem & { key: string })) {
+  return item.type === "file" && !!item.comment?.trim()
+}
+
 function createPromptActions(
   setStore: SetStoreFunction<{
     prompt: Prompt
@@ -189,6 +193,26 @@ function createPromptSession(dir: string, id: string | undefined) {
       remove(key: string) {
         setStore("context", "items", (items) => items.filter((x) => x.key !== key))
       },
+      removeComment(path: string, commentID: string) {
+        setStore("context", "items", (items) =>
+          items.filter((item) => !(item.type === "file" && item.path === path && item.commentID === commentID)),
+        )
+      },
+      updateComment(path: string, commentID: string, next: Partial<FileContextItem> & { comment?: string }) {
+        setStore("context", "items", (items) =>
+          items.map((item) => {
+            if (item.type !== "file" || item.path !== path || item.commentID !== commentID) return item
+            const value = { ...item, ...next }
+            return { ...value, key: contextItemKey(value) }
+          }),
+        )
+      },
+      replaceComments(items: FileContextItem[]) {
+        setStore("context", "items", (current) => [
+          ...current.filter((item) => !isCommentItem(item)),
+          ...items.map((item) => ({ ...item, key: contextItemKey(item) })),
+        ])
+      },
     },
     set: actions.set,
     reset: actions.reset,
@@ -251,6 +275,10 @@ export const { use: usePrompt, provider: PromptProvider } = createSimpleContext(
         items: () => session().context.items(),
         add: (item: ContextItem) => session().context.add(item),
         remove: (key: string) => session().context.remove(key),
+        removeComment: (path: string, commentID: string) => session().context.removeComment(path, commentID),
+        updateComment: (path: string, commentID: string, next: Partial<FileContextItem> & { comment?: string }) =>
+          session().context.updateComment(path, commentID, next),
+        replaceComments: (items: FileContextItem[]) => session().context.replaceComments(items),
       },
       set: (prompt: Prompt, cursorPosition?: number) => session().set(prompt, cursorPosition),
       reset: () => session().reset(),