Fix misreported number of lines being removed by model (#12076)

packages/core/src/tools/edit.test.ts

@@ -1114,4 +1114,89 @@ describe('EditTool', () => {
       expect(params.new_string).toBe(modifiedContent);
     });
   });
+
+  describe('multiple file edits', () => {
+    it('should perform multiple removals and report correct diff stats', async () => {
+      const numFiles = 10;
+      const files: Array<{
+        path: string;
+        initialContent: string;
+        toRemove: string;
+      }> = [];
+      const expectedLinesRemoved: number[] = [];
+      const actualLinesRemoved: number[] = [];
+
+      // 1. Create 10 files with 5-10 lines each
+      for (let i = 0; i < numFiles; i++) {
+        const fileName = `test-file-${i}.txt`;
+        const filePath = path.join(rootDir, fileName);
+        const numLines = Math.floor(Math.random() * 6) + 5; // 5 to 10 lines
+        const lines = Array.from(
+          { length: numLines },
+          (_, j) => `File ${i}, Line ${j + 1}`,
+        );
+        const content = lines.join('\n') + '\n';
+
+        // Determine which lines to remove (2 or 3 lines)
+        const numLinesToRemove = Math.floor(Math.random() * 2) + 2; // 2 or 3
+        expectedLinesRemoved.push(numLinesToRemove);
+        const startLineToRemove = 1; // Start removing from the second line
+        const linesToRemove = lines.slice(
+          startLineToRemove,
+          startLineToRemove + numLinesToRemove,
+        );
+        const toRemove = linesToRemove.join('\n') + '\n';
+
+        fs.writeFileSync(filePath, content, 'utf8');
+        files.push({
+          path: filePath,
+          initialContent: content,
+          toRemove,
+        });
+      }
+
+      // 2. Create and execute 10 tool calls for removal
+      for (const file of files) {
+        const params: EditToolParams = {
+          file_path: file.path,
+          old_string: file.toRemove,
+          new_string: '', // Removing the content
+        };
+        const invocation = tool.build(params);
+        const result = await invocation.execute(new AbortController().signal);
+
+        if (
+          result.returnDisplay &&
+          typeof result.returnDisplay === 'object' &&
+          'diffStat' in result.returnDisplay &&
+          result.returnDisplay.diffStat
+        ) {
+          actualLinesRemoved.push(
+            result.returnDisplay.diffStat?.model_removed_lines,
+          );
+        } else if (result.error) {
+          console.error(`Edit failed for ${file.path}:`, result.error);
+        }
+      }
+
+      // 3. Assert that the content was removed from each file
+      for (const file of files) {
+        const finalContent = fs.readFileSync(file.path, 'utf8');
+        const expectedContent = file.initialContent.replace(file.toRemove, '');
+        expect(finalContent).toBe(expectedContent);
+        expect(finalContent).not.toContain(file.toRemove);
+      }
+
+      // 4. Assert that the total number of removed lines matches the diffStat total
+      const totalExpectedRemoved = expectedLinesRemoved.reduce(
+        (sum, current) => sum + current,
+        0,
+      );
+      const totalActualRemoved = actualLinesRemoved.reduce(
+        (sum, current) => sum + current,
+        0,
+      );
+      expect(totalActualRemoved).toBe(totalExpectedRemoved);
+    });
+  });
 });

packages/core/src/tools/smart-edit.test.ts

@@ -660,4 +660,91 @@ describe('SmartEditTool', () => {
       calculateSpy.mockRestore();
     });
   });
+
+  describe('multiple file edits', () => {
+    it('should perform multiple removals and report correct diff stats', async () => {
+      const numFiles = 10;
+      const files: Array<{
+        path: string;
+        initialContent: string;
+        toRemove: string;
+      }> = [];
+      const expectedLinesRemoved: number[] = [];
+      const actualLinesRemoved: number[] = [];
+
+      // 1. Create 10 files with 5-10 lines each
+      for (let i = 0; i < numFiles; i++) {
+        const fileName = `test-file-${i}.txt`;
+        const filePath = path.join(rootDir, fileName);
+        const numLines = Math.floor(Math.random() * 6) + 5; // 5 to 10 lines
+        const lines = Array.from(
+          { length: numLines },
+          (_, j) => `File ${i}, Line ${j + 1}`,
+        );
+        const content = lines.join('\n') + '\n';
+
+        // Determine which lines to remove (2 or 3 lines)
+        const numLinesToRemove = Math.floor(Math.random() * 2) + 2; // 2 or 3
+        expectedLinesRemoved.push(numLinesToRemove);
+        const startLineToRemove = 1; // Start removing from the second line
+        const linesToRemove = lines.slice(
+          startLineToRemove,
+          startLineToRemove + numLinesToRemove,
+        );
+        const toRemove = linesToRemove.join('\n') + '\n';
+
+        fs.writeFileSync(filePath, content, 'utf8');
+        files.push({
+          path: filePath,
+          initialContent: content,
+          toRemove,
+        });
+      }
+
+      // 2. Create and execute 10 tool calls for removal
+      for (const file of files) {
+        const params: EditToolParams = {
+          file_path: file.path,
+          instruction: `Remove lines from the file`,
+          old_string: file.toRemove,
+          new_string: '', // Removing the content
+          ai_proposed_string: '',
+        };
+        const invocation = tool.build(params);
+        const result = await invocation.execute(new AbortController().signal);
+
+        if (
+          result.returnDisplay &&
+          typeof result.returnDisplay === 'object' &&
+          'diffStat' in result.returnDisplay &&
+          result.returnDisplay.diffStat
+        ) {
+          actualLinesRemoved.push(
+            result.returnDisplay.diffStat?.model_removed_lines,
+          );
+        } else if (result.error) {
+          console.error(`Edit failed for ${file.path}:`, result.error);
+        }
+      }
+
+      // 3. Assert that the content was removed from each file
+      for (const file of files) {
+        const finalContent = fs.readFileSync(file.path, 'utf8');
+        const expectedContent = file.initialContent.replace(file.toRemove, '');
+        expect(finalContent).toBe(expectedContent);
+        expect(finalContent).not.toContain(file.toRemove);
+      }
+
+      // 4. Assert that the total number of removed lines matches the diffStat total
+      const totalExpectedRemoved = expectedLinesRemoved.reduce(
+        (sum, current) => sum + current,
+        0,
+      );
+      const totalActualRemoved = actualLinesRemoved.reduce(
+        (sum, current) => sum + current,
+        0,
+      );
+      expect(totalActualRemoved).toBe(totalExpectedRemoved);
+    });
+  });
 });

packages/core/src/tools/smart-edit.ts

@@ -763,12 +763,11 @@ class EditToolInvocation
           'Proposed',
           DEFAULT_DIFF_OPTIONS,
         );
-        const originallyProposedContent =
-          this.params.ai_proposed_string || this.params.new_string;
+
         const diffStat = getDiffStat(
           fileName,
           editData.currentContent ?? '',
-          originallyProposedContent,
+          editData.newContent,
           this.params.new_string,
         );
         displayResult = {