From 894b443d6a9d214dfd70332ad73f3122091266e4 Mon Sep 17 00:00:00 2001
From: waleedcodes <110061477+waleedcodes@users.noreply.github.com>
Date: Fri, 9 Oct 2026 21:24:05 +0500
Subject: [PATCH 1/3] test(diff): scaffold diff parser test suite

---
 tests/diffParser.test.ts | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)
 create mode 100644 tests/diffParser.test.ts

diff --git a/tests/diffParser.test.ts b/tests/diffParser.test.ts
new file mode 100644
index 0000000..5fce140
--- /dev/null
+++ b/tests/diffParser.test.ts
@@ -0,0 +1,19 @@
+import { describe, expect, it } from 'vitest';
+import { DiffParser } from '../src/git/diffParser';
+
+describe('DiffParser', () => {
+  it('should parse an empty diff without error', () => {
+    const result = DiffParser.parse('', '/test/root');
+    expect(result.files).toHaveLength(0);
+    expect(result.totalFilesChanged).toBe(0);
+    expect(result.totalInsertions).toBe(0);
+    expect(result.totalDeletions).toBe(0);
+  });
+
+  it('should parse a standard unified diff with additions and deletions', () => {
+    const sampleDiff = `diff --git a/src/user.ts b/src/user.ts
+index e69de29..49e29a1 100644
+--- a/src/user.ts
++++ b/src/user.ts
+@@ -10,3 +10,5 @@ export function getUser(id: string) {
+-  return db.user.find(id);

From 05cd1881e47cb15347ab65383d1e56a44b23b6f5 Mon Sep 17 00:00:00 2001
From: waleedcodes <110061477+waleedcodes@users.noreply.github.com>
Date: Fri, 9 Oct 2026 21:24:05 +0500
Subject: [PATCH 2/3] test(diff): test single file added and deleted line
 extraction

---
 tests/diffParser.test.ts | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/tests/diffParser.test.ts b/tests/diffParser.test.ts
index 5fce140..d7e071d 100644
--- a/tests/diffParser.test.ts
+++ b/tests/diffParser.test.ts
@@ -17,3 +17,25 @@ index e69de29..49e29a1 100644
 +++ b/src/user.ts
 @@ -10,3 +10,5 @@ export function getUser(id: string) {
 -  return db.user.find(id);
++  const user = await db.user.findUnique({ where: { id } });
++  return user;
+ }
++export function deleteUser() {}
+`;
+
+    const result = DiffParser.parse(sampleDiff, '/workspace');
+    expect(result.files).toHaveLength(1);
+    const file = result.files[0];
+    expect(file.newPath).toBe('src/user.ts');
+    expect(file.addedLines).toEqual([10, 11, 13]);
+    expect(file.deletedLines).toEqual([10]);
+    expect(file.modifiedLineRanges).toEqual([
+      { start: 10, end: 11 },
+      { start: 13, end: 13 }
+    ]);
+  });
+
+  it('should identify new files correctly', () => {
+    const newFileDiff = `diff --git a/src/new-route.ts b/src/new-route.ts
+new file mode 100644
+index 0000000..49e29a1

From ecc325008989485546a2c3f44b97f71f239a98e3 Mon Sep 17 00:00:00 2001
From: waleedcodes <110061477+waleedcodes@users.noreply.github.com>
Date: Fri, 9 Oct 2026 21:24:05 +0500
Subject: [PATCH 3/3] test(diff): test multi-file diff parsing and empty diff
 edge cases

---
 tests/diffParser.test.ts | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/tests/diffParser.test.ts b/tests/diffParser.test.ts
index d7e071d..8a69cda 100644
--- a/tests/diffParser.test.ts
+++ b/tests/diffParser.test.ts
@@ -39,3 +39,17 @@ index e69de29..49e29a1 100644
     const newFileDiff = `diff --git a/src/new-route.ts b/src/new-route.ts
 new file mode 100644
 index 0000000..49e29a1
+--- /dev/null
++++ b/src/new-route.ts
+@@ -0,0 +1,3 @@
++export async function GET() {
++  return Response.json({ status: 'ok' });
++}
+`;
+
+    const result = DiffParser.parse(newFileDiff, '/workspace');
+    expect(result.files).toHaveLength(1);
+    expect(result.files[0].isNew).toBe(true);
+    expect(result.files[0].addedLines).toEqual([1, 2, 3]);
+  });
+});