clean: remove recovery from unified diff in add/delete file changes

incorrect assumption that add/diff changes may have unified diff

Author: AlexandrSuhinin

src/CodexToolCallMapper.ts

@@ -274,17 +274,10 @@ async function createPatchContent(change: FileUpdateChange): Promise<ToolCallCon
 }
 
 async function createAddFileContent(change: FileUpdateChange): Promise<ToolCallContent | null> {
-    let newText;
-    if (isUnifiedDiff(change.diff)) {
-        newText = applyPatch("", change.diff)
-        if (!newText) return null;
-    } else {
-        newText = change.diff;
-    }
     return {
         type: "diff",
         oldText: null,
-        newText: newText,
+        newText: change.diff, // app-server always returns file content instead of diff
         path: change.path,
         _meta: {
             kind: "add",
@@ -338,13 +331,9 @@ function createUpdateDiffContent(path: string, oldText: string, newText: string)
 }
 
 async function createDeleteFileContent(change: FileUpdateChange): Promise<ToolCallContent> {
-    // If the patch deletes a file, the old content may be only available from the diff.
-    const fileContent = await readFileContent(change.path);
-    const oldContent = fileContent ?? (isUnifiedDiff(change.diff) ? patchToDeletedContent(change.diff) : change.diff);
-
     return {
         type: "diff",
-        oldText: oldContent,
+        oldText: change.diff, // app-server always returns file content instead of diff
         newText: "",
         path: change.path,
         _meta: {
@@ -364,44 +353,3 @@ async function readFileContent(filePath: string): Promise<string | null> {
 function recoverCorruptedDiff(diff: string): string {
     return diff.replace(/\nMoved to: .*$/, "");
 }
-
-function isUnifiedDiff(content: string): boolean {
-    return content.startsWith("--- ") || content.includes("\n--- ");
-}
-
-/**
- * Recreates the content of a deleted file from the unified diff.
- * @param unifiedDiff The unified diff of the file deletion patch
- */
-function patchToDeletedContent(unifiedDiff: string): string | null {
-    try {
-        const [patch] = parsePatch(unifiedDiff);
-        if (!patch || patch.hunks.length === 0) {
-            return null;
-        }
-
-        const oldLines: string[] = [];
-        let hasNoTrailingNewlineMarker = false;
-
-        for (const hunk of patch.hunks) {
-            for (const line of hunk.lines) {
-                if (line === "\\ No newline at end of file") {
-                    hasNoTrailingNewlineMarker = true;
-                    continue;
-                }
-                if (line.startsWith("-") || line.startsWith(" ")) {
-                    oldLines.push(line.slice(1));
-                }
-            }
-        }
-
-        if (oldLines.length === 0) {
-            return "";
-        }
-
-        const oldText = oldLines.join("\n");
-        return hasNoTrailingNewlineMarker || !unifiedDiff.endsWith("\n") ? oldText : `${oldText}\n`;
-    } catch {
-        return null;
-    }
-}

src/__tests__/CodexACPAgent/file-change-events.test.ts

@@ -55,14 +55,7 @@ describe('CodexEventHandler - file change events', () => {
                         {
                             path: '/test/project/NewFile.kt',
                             kind: { type: 'add' },
-                            diff: `--- /dev/null
-+++ /test/project/NewFile.kt
-@@ -0,0 +1,5 @@
-+package test.project
-+
-+class NewFile {
-+    fun hello() = "Hello"
-+}`,
+                            diff: 'package test.project\n\nclass NewFile {\n    fun hello() = "Hello"\n}\n',
                         },
                     ],
                     status: 'completed',
@@ -90,18 +83,12 @@ describe('CodexEventHandler - file change events', () => {
                         {
                             path: '/test/project/FileA.kt',
                             kind: { type: 'add' },
-                            diff: `--- /dev/null
-+++ /test/project/FileA.kt
-@@ -0,0 +1 @@
-+class FileA`,
+                            diff: 'class FileA\n',
                         },
                         {
                             path: '/test/project/FileB.kt',
                             kind: { type: 'add' },
-                            diff: `--- /dev/null
-+++ /test/project/FileB.kt
-@@ -0,0 +1 @@
-+class FileB`,
+                            diff: 'class FileB\n',
                         },
                     ],
                     status: 'completed',
@@ -158,12 +145,7 @@ describe('CodexEventHandler - file change events', () => {
                         {
                             path: '/test/project/OldFile.kt',
                             kind: { type: 'delete' },
-                            diff: `--- /test/project/OldFile.kt
-+++ /dev/null
-@@ -1,3 +0,0 @@
--package test.project
--
--class OldFile {}`,
+                            diff: 'package test.project\n\nclass OldFile {}',
                         },
                     ],
                     status: 'completed',
@@ -224,12 +206,7 @@ describe('CodexEventHandler - file change events', () => {
                         {
                             path: '/test/project/OldFile.kt',
                             kind: { type: 'delete' },
-                            diff: `--- /test/project/OldFile.kt
-+++ /dev/null
-@@ -1,3 +0,0 @@
--package test.project
--
--class OldFile {}`,
+                            diff: 'package test.project\n\nclass OldFile {}',
                         },
                     ],
                     status: 'completed',
@@ -274,19 +251,19 @@ describe('CodexEventHandler - file change events', () => {
         );
     });
 
-    it('should ignore broken unified diffs in file changes', async () => {
-        const fileChange: ThreadItem = {
+    it('should ignore broken unified diffs in update file changes', async () => {
+        const fileChange: ThreadItem & { type: 'fileChange' } = {
             type: 'fileChange',
             id: 'file-change-broken-diff',
             changes: [
                 {
-                    path: '/test/project/BrokenFile.kt',
-                    kind: { type: 'add' },
+                    path: '/test/project/OldFile.kt',
+                    kind: { type: 'update', move_path: null },
                     diff:
-`--- /dev/null
-+++ /test/project/BrokenFile.kt
+`--- /test/project/OldFile.kt
++++ /test/project/OldFile.kt
 @@ broken @@
-+class BrokenFile
++class UpdatedFile
 `,
                 },
             ],

src/__tests__/CodexACPAgent/load-session.test.ts

@@ -108,13 +108,8 @@ describe("CodexACPAgent - loadSession", () => {
                                 {
                                     path: "/test/project/Added.txt",
                                     kind: { type: "add" },
-                                    diff: `--- /dev/null
-+++ /test/project/Added.txt
-@@ -0,0 +1,2 @@
-+Hello
-+World
-`,
-                                },
+                                    diff: "Hello\nWorld\n",
+                                }
                             ],
                             status: "completed",
                         },