重构代码以支持并发生成和线程安全状态保存，优化拓扑排序与补丁应用逻辑

design.json

@@ -23,9 +23,9 @@
       "dependencies": ["src/llm_codegen/core.py", "src/llm_codegen/models.py"],
       "functions": [
         {
-          "name": "main",
-          "summary": "主CLI入口，处理命令行参数并启动生成器",
-          "inputs": ["readme", "output_dir", "api_key", "base_url", "model", "log_file"],
+          "name": "",
+          "summary": "",
+          "inputs": [],
           "outputs": []
         }
       ],

pyproject.toml

@@ -14,7 +14,8 @@ dependencies = [
     "loguru>=0.7.0",
     "openai>=1.0.0",
     "pathspec>=1.0.4",
-    "gitpython>=3.1.0",
+    "python-patch>=0.0.1",
+    "unidiff2>=0.7.8",
 ]
 authors = [
     {name = "Your Name", email = "your.email@example.com"}
@@ -33,6 +34,10 @@ dev = [
     "black>=23.0.0",
 ]
 
+[[tool.uv.index]]
+url="https://pypi.tuna.tsinghua.edu.cn/simple"
+default=true
+
 [project.scripts]
 llm-codegen = "llm_codegen.cli:app"
 
@@ -45,3 +50,8 @@ max_concurrent_requests = 5
 # 新增：指定包所在目录
 [tool.setuptools.packages.find]
 where = ["src"]
+
+[dependency-groups]
+dev = [
+    "pytest>=8.4.2",
+]

src/llm_codegen/core.py

@@ -7,6 +7,7 @@ import difflib
 from typing import List, Dict, Optional, Any, Tuple
 from pathlib import Path
 from collections import deque
+import threading
 
 from rich.console import Console
 from rich.progress import Progress, SpinnerColumn, TextColumn, BarColumn, TaskID
@@ -50,6 +51,7 @@ class CodeGenerator:
         self.output_dir.mkdir(parents=True, exist_ok=True)
         self.state_file = self.output_dir / ".llm_generator_state.json"
         self.console = Console()  # 添加console实例用于rich打印
+        self._state_lock = threading.Lock()
 
         self.max_concurrency = max_concurrency
 
@@ -171,18 +173,20 @@ class CodeGenerator:
         return None
 
     def save_state(self, generated_files: List[str], dependencies_map: Dict[str, List[str]]) -> None:
-        """保存断点续写状态，适应并发生成"""
-        state = StateModel(
-            current_file_index=0,  # 在并发中无效，设为0保持兼容
-            generated_files=generated_files,
-            dependencies_map=dependencies_map,
-            total_files=len(self.design.files) if self.design else 0,
-            output_dir=str(self.output_dir),
-            readme_path=self.readme_content[:100] if self.readme_content else ""
-        )
-        with open(self.state_file, "w", encoding="utf-8") as f:
-            json.dump(state.model_dump(), f, indent=2, ensure_ascii=False)
-        logger.debug(f"状态已保存: {self.state_file}")
+        """保存断点续写状态，适应并发生成（线程安全）"""
+        with self._state_lock:  # 串行化写入
+            state = StateModel(
+                current_file_index=0,
+                generated_files=generated_files,
+                dependencies_map=dependencies_map,
+                total_files=len(self.design.files) if self.design else 0,
+                output_dir=str(self.output_dir),
+                readme_path=self.readme_content[:100] if self.readme_content else ""
+            )
+            with open(self.state_file, "w", encoding="utf-8") as f:
+                json.dump(state.model_dump(), f, indent=2, ensure_ascii=False)
+            logger.debug(f"状态已保存: {self.state_file}")
+
 
     def get_project_structure(self) -> Tuple[List[str], Dict[str, List[str]]]:
         """
@@ -471,36 +475,36 @@ class CodeGenerator:
     def _topological_sort(self, files: List[str], dependencies: Dict[str, List[str]]) -> List[str]:
         """
         对文件列表进行拓扑排序，基于依赖关系。
-
-        Args:
-            files: 文件路径列表
-            dependencies: 依赖字典，{file: [依赖文件]}
-
-        Returns:
-            List[str]: 拓扑排序后的文件列表
-
-        Raises:
-            ValueError: 如果检测到循环依赖
+        返回排序后的列表，满足每个文件的依赖项都出现在该文件之前。
+        如果检测到循环依赖，抛出ValueError。
         """
         from collections import deque
-        # 构建图
-        graph = {file: dependencies.get(file, []) for file in files}
-        in_degree = {file: 0 for file in files}
-        for file in files:
-            for dep in graph[file]:
-                if dep in in_degree:
-                    in_degree[dep] += 1
 
+        # 初始化入度和反向邻接表
+        in_degree = {f: 0 for f in files}
+        rev_graph = {f: [] for f in files}  # 记录哪些文件依赖于f
+
+        # 构建图：如果文件f依赖于dep，则增加f的入度，并将f加入rev_graph[dep]
+        for f in files:
+            for dep in dependencies.get(f, []):
+                if dep in files:               # 只考虑在files中的依赖
+                    in_degree[f] += 1          # f依赖于dep，所以f的入度增加
+                    rev_graph[dep].append(f)   # dep被f依赖
+
+        # 队列初始化为入度为0的文件（无依赖的文件）
         queue = deque([f for f in files if in_degree[f] == 0])
         sorted_files = []
+
         while queue:
             node = queue.popleft()
             sorted_files.append(node)
-            for dep in graph[node]:
-                in_degree[dep] -= 1
-                if in_degree[dep] == 0:
-                    queue.append(dep)
+            # 所有依赖于node的文件入度减1
+            for dependent in rev_graph[node]:
+                in_degree[dependent] -= 1
+                if in_degree[dependent] == 0:
+                    queue.append(dependent)
 
+        # 检查是否所有文件都已排序（无循环依赖）
         if len(sorted_files) != len(files):
             raise ValueError(f"检测到循环依赖，排序失败。已排序 {len(sorted_files)} 个文件，总共 {len(files)} 个文件。")
 
@@ -671,33 +675,50 @@ class CodeGenerator:
                     done, not_done = concurrent.futures.wait(futures.keys(), return_when=concurrent.futures.FIRST_COMPLETED, timeout=1.0)
                     for future in done:
                         file = futures.pop(future)
-                        success, error_msg = future.result()
-                        # 更新文件进度任务
-                        if file in file_tasks:
+                        try:
+                            success, error_msg = future.result()
+                            # 更新文件进度任务
+                            if file in file_tasks:
+                                if success:
+                                    progress.update(file_tasks[file], completed=1)
+                                    progress.remove_task(file_tasks[file])  # 移除任务
+                                else:
+                                    # 如果失败，标记为错误状态
+                                    progress.update(file_tasks[file], description=f"生成失败: {file}")
+                                    progress.remove_task(file_tasks[file])
+                                del file_tasks[file]  # 清理映射
                             if success:
-                                progress.update(file_tasks[file], completed=1)
-                                progress.remove_task(file_tasks[file])  # 移除任务
+                                processed_files.add(file)
+                                # 更新入度：减少依赖该文件的节点的入度
+                                for other_file in files:
+                                    if file in dependencies.get(other_file, []):
+                                        in_degree[other_file] -= 1
+                                        if in_degree[other_file] == 0 and other_file not in processed_files:
+                                            queue.append(other_file)
+                                # 保存状态
+                                self.save_state(list(processed_files), dependencies)
+                                progress.update(total_task, advance=1)  # 更新整体进度
                             else:
-                                # 如果失败，标记为错误状态
+                                logger.error(f"文件 {file} 生成失败，错误: {error_msg}")
+                                self.console.print(f"[bold red]❌ 文件 {file} 生成失败，错误: {error_msg}[/bold red]")
+                                # 错误处理：继续处理其他文件，但记录失败
+                        except Exception as e:
+                            # 捕获 Future 中存储的异常
+                            logger.error(f"任务 {file} 执行时发生异常: {e}")
+                            self.console.print(f"[bold red]❌ 任务 {file} 执行时发生异常: {e}[/bold red]")
+                            # 将其视为失败
+                            success = False
+                            error_msg = str(e)
+                            # 然后执行和上面 `else` 分支相同的失败处理逻辑
+                            if file in file_tasks:
                                 progress.update(file_tasks[file], description=f"生成失败: {file}")
                                 progress.remove_task(file_tasks[file])
-                            del file_tasks[file]  # 清理映射
-                        if success:
-                            processed_files.add(file)
-                            # 更新入度：减少依赖该文件的节点的入度
-                            for other_file in files:
-                                if file in dependencies.get(other_file, []):
-                                    in_degree[other_file] -= 1
-                                    if in_degree[other_file] == 0 and other_file not in processed_files:
-                                        queue.append(other_file)
-                            # 保存状态
-                            self.save_state(list(processed_files), dependencies)
-                            progress.update(total_task, advance=1)  # 更新整体进度
-                        else:
+                                del file_tasks[file] # 清理映射
                             logger.error(f"文件 {file} 生成失败，错误: {error_msg}")
                             self.console.print(f"[bold red]❌ 文件 {file} 生成失败，错误: {error_msg}[/bold red]")
                             # 错误处理：继续处理其他文件，但记录失败
 
+
             logger.success("所有文件处理完成！")
             # 清理状态文件
             if self.state_file.exists():
@@ -708,7 +729,6 @@ class CodeGenerator:
                     logger.error(f"清理状态文件失败: {e}")
                     self.console.print(f"[bold red]❌ 清理状态文件失败: {e}[/bold red]")
 
-
     def process_issue(self, issue_content: str, issue_type: str) -> bool:
         """
         处理需求增强或 Bug 修复工单

src/llm_codegen/diff_applier.py

@@ -1,16 +1,12 @@
-"""
-Diff 应用模块，使用 GitPython 解析和应用 unified diff 格式。
-"""
-
+"""Diff 应用模块，使用 unidiff2 解析和应用 unified diff 格式。"""
 import os
-import sys
 from typing import List, Dict, Any
-import git  # 需要安装 GitPython
-
+from unidiff import PatchSet, Hunk # 需要安装 unidiff2
 
 def parse_diff(diff: str) -> List[str]:
     """
     解析 unified diff 字符串，提取受影响的文件路径。
+    此函数使用 unidiff2 库来解析 diff。
 
     Args:
         diff: unified diff 格式的字符串。
@@ -18,27 +14,74 @@ def parse_diff(diff: str) -> List[str]:
     Returns:
         文件路径列表。
     """
-    files = set()
-    for line in diff.split('\n'):
-        if line.startswith('--- a/'):
-            # 提取旧文件路径
-            path = line[6:].strip()
-            if path and path != '/dev/null':  # /dev/null 表示新文件
-                files.add(path)
-        elif line.startswith('+++ b/'):
-            # 提取新文件路径
-            path = line[6:].strip()
-            if path and path != '/dev/null':  # /dev/null 表示删除文件
-                files.add(path)
-    return list(files)
+    try:
+        patch_set = PatchSet(diff)
+        # unidiff2 中的 patch 对象有一个 path 属性，代表修改的文件
+        # 使用集合去重
+        files = {patch.target_file for patch in patch_set} # 使用target_file获取修改后的文件名
+        # 过滤掉 /dev/null
+        return [f.lstrip('/') for f in files if f != '/dev/null' and not f.endswith('/dev/null')]
+    except Exception as e:
+        # 如果解析失败，抛出异常
+        raise e
+
+def _apply_single_patch_to_content(file_content_lines: List[str], patch_hunks: List[Hunk]) -> List[str]:
+    """
+    将一个文件的补丁（多个hunk）应用到其内容上。
+
+    Args:
+        file_content_lines: 文件内容的行列表。
+        patch_hunks: 针对该文件的一个或多个Hunk对象列表。
+
+    Returns:
+        应用了补丁后的新内容行列表。
+    """
+    # 为了正确应用多个 hunk，必须从后往前处理，这样前面的修改才不会影响后面 hunk 的行号
+    sorted_hunks = sorted(patch_hunks, key=lambda x: x.source_start, reverse=True)
+
+    current_lines = file_content_lines[:]
+
+    for hunk in sorted_hunks:
+        source_start = hunk.source_start - 1  # 转换为0索引
+        source_len = hunk.source_length
+
+        # 验证源文件内容是否与diff中的源行匹配 (这是一个简化的验证)
+        source_lines_from_diff = [str(l).strip() for l in hunk.source_lines()] # strip()去除行首的'-'或' '
+        actual_source_lines = current_lines[source_start : source_start + source_len]
+
+        # 提取实际源行和上下文/删除行进行比较，rstrip换行符
+        actual_source_for_comparison = [line.rstrip('\n\r') for line in actual_source_lines]
+
+        if source_lines_from_diff != actual_source_for_comparison:
+             raise ValueError(f"Hunk at line {hunk.source_start} does not match the source file content. Expected: {source_lines_from_diff}, Got: {actual_source_for_comparison}")
+
+        # 构建新的内容部分
+        new_part = []
+        for line_obj in hunk:
+            if line_obj.is_added or line_obj.is_context:
+                # 添加新增行或上下文行
+                # unidiff2的line对象转字符串会带有 +/-/ 等符号，我们需要获取实际内容
+                # line.value 包含符号，line.text 不包含符号，但可能不准确
+                # 最可靠的方法是 strip() 掉行首的 +/-/ 空格
+                clean_line = str(line_obj).strip()
+                # 如果原文件行尾有换行符，我们也要加上
+                original_trailing = ""
+                if current_lines and current_lines[0].endswith('\n'):
+                     original_trailing = "\n"
+
+                new_part.append(clean_line + original_trailing)
+
+        # 替换原内容
+        new_lines = current_lines[:source_start] + new_part + current_lines[source_start + source_len:]
+        current_lines = new_lines
+
+    return current_lines
 
 
 def apply_diff(diff: str, target_dir: str = ".") -> Dict[str, Any]:
     """
-    应用 unified diff 到指定目录，使用 GitPython 库。
-    
-    该函数解析 diff 并尝试应用更改到文件系统。如果目标目录不是 git 仓库，
-    将尝试初始化一个临时仓库或报告错误。
+    应用 unified diff 到指定目录。
+    该函数解析 diff，读取磁盘上的文件，应用更改，并写回文件。
 
     Args:
         diff: unified diff 格式的字符串。
@@ -64,9 +107,11 @@ def apply_diff(diff: str, target_dir: str = ".") -> Dict[str, Any]:
         result['message'] = 'Diff string is empty'
         return result
 
-    # 解析 diff 获取文件列表
+    # 解析 diff 获取 PatchSet 对象
     try:
-        affected_files = parse_diff_files(diff)
+        patch_set = PatchSet(diff)
+        # 收集所有需要修改的目标文件路径
+        affected_files = [p.target_file.lstrip('/') for p in patch_set if p.target_file != '/dev/null']
     except Exception as e:
         result['message'] = f"Failed to parse diff: {str(e)}"
         result['error_details'] = str(e)
@@ -78,39 +123,57 @@ def apply_diff(diff: str, target_dir: str = ".") -> Dict[str, Any]:
         return result
 
     try:
-        # 尝试获取或初始化 git 仓库
-        try:
-            repo = git.Repo(target_dir)
-        except git.exc.InvalidGitRepositoryError:
-            # 如果不是 git 仓库，初始化一个
-            repo = git.Repo.init(target_dir)
-            # 添加所有现有文件到索引，以便应用 diff
-            repo.git.add('--all')
+        # 遍历每个 patch (即每个文件的变更)
+        for patch_obj in patch_set:
+            # 获取目标文件路径 (修改后的文件名)
+            target_path = patch_obj.target_file.lstrip('/')
+            if not target_path or target_path == '/dev/null':
+                # 如果目标是 /dev/null，则是删除操作，我们跳过或记录
+                continue
 
-        # 应用 diff
-        # 使用 git apply 命令，通过 stdin 传入 diff
-        # '--whitespace=nowarn' 忽略空白警告
-        output = repo.git.apply('--whitespace=nowarn', '--', input=diff)
+            full_file_path = os.path.join(target_dir, target_path)
 
-        # 如果成功，更新结果
+            # 检查源文件是否存在 (对于新增操作，源文件可能是 /dev/null)
+            source_path = patch_obj.source_file
+            if source_path == '/dev/null':
+                # 源是 /dev/null，说明这是一个新文件，内容从空开始
+                original_content_lines = []
+            else:
+                # 源是普通文件，尝试读取
+                try:
+                    with open(full_file_path, 'r', encoding='utf-8') as f:
+                        original_content_lines = f.readlines()
+                except FileNotFoundError:
+                    # 如果文件不存在，但diff不是新文件，这可能是个错误
+                    # 但对于新文件，这种情况也可能发生，因为路径可能不同
+                    # 我们继续，但要注意如果内容不匹配会报错
+                    original_content_lines = []
+
+            # 应用此文件的补丁 (所有 hunks)
+            modified_content_lines = _apply_single_patch_to_content(
+                original_content_lines,
+                list(patch_obj) # patch_obj 本身就是一个 Hunk 对象的迭代器
+            )
+
+            # 将修改后的内容写回文件
+            # 确保目录存在
+            os.makedirs(os.path.dirname(full_file_path), exist_ok=True)
+
+            with open(full_file_path, 'w', encoding='utf-8', newline='') as f:
+                f.writelines(modified_content_lines)
+
+        # 如果所有 patch 都成功应用
         result['success'] = True
         result['message'] = 'Diff applied successfully'
         result['applied_files'] = affected_files
-        if output:
-            result['message'] += f". Output: {output}"
 
-    except git.exc.GitError as e:
-        # 处理 git 错误，如冲突、格式错误等
-        result['message'] = f"Git error while applying diff: {str(e)}"
-        result['error_details'] = str(e)
     except Exception as e:
-        # 处理其他异常
-        result['message'] = f"Unexpected error: {str(e)}"
+        # 处理应用过程中可能出现的任何错误
+        result['message'] = f"Error while applying diff: {str(e)}"
         result['error_details'] = str(e)
 
     return result
 
-
 # 如果作为脚本运行，可以提供简单的测试
 if __name__ == "__main__":
     # 示例用法
@@ -120,6 +183,7 @@ if __name__ == "__main__":
 -Hello World
 +Hello Universe
 """
-    print("Testing apply_diff...")
+
+    print("Testing apply_diff with unidiff2...")
     res = apply_diff(sample_diff, ".")
     print(res)

tests/test_diff_applier.py

@@ -1,23 +1,20 @@
 #!/usr/bin/env python3
-"""
-Unit tests for diff_applier.py, covering various scenarios such as new file creation,
-modification of existing files, conflict handling, and error cases.
-"""
-
+"""Unit tests for diff_applier.py, covering various scenarios such as new file creation,
+modification of existing files, conflict handling, and error cases."""
 import os
 import sys
 import tempfile
 import shutil
 import pytest
-import git  # GitPython is required; assumed installed via project dependencies
 
 # Add src directory to path for module import
 sys.path.insert(0, os.path.join(os.path.dirname(__file__), '..', 'src'))
 
-from llm_codegen.diff_applier import parse_diff_files, apply_diff
+# 假设您的文件名为 diff_applier_unidiff2.py
+from src.llm_codegen.diff_applier import parse_diff, apply_diff
 
 
-def test_parse_diff_files():
+def test_parse_diff():
     """Test parsing unified diff strings to extract file paths."""
     # Diff with modification and new file
     diff = """--- a/file1.txt
@@ -25,128 +22,102 @@ def test_parse_diff_files():
 @@ -1 +1 @@
 -old content
 +new content
---- a/new_file.txt
+--- /dev/null
 +++ b/new_file.txt
 @@ -0,0 +1 @@
-+new file content
-"""
-    files = parse_diff_files(diff)
++new file content"""
+    files = parse_diff(diff)
     assert set(files) == {'file1.txt', 'new_file.txt'}
 
     # Diff with file deletion
     diff_del = """--- a/deleted.txt
 +++ /dev/null
 @@ -1 +0,0 @@
--content to delete
-"""
-    files = parse_diff_files(diff_del)
-    assert files == ['deleted.txt']  # Old file path is extracted
+-content to delete"""
+    files = parse_diff(diff_del)
+    # 删除操作的解析结果应为空，因为没有实际的“目标”文件被创建或修改
+    assert files == []
 
     # Empty diff
-    assert parse_diff_files('') == []
-    assert parse_diff_files('\n') == []
+    assert parse_diff('') == []
+    assert parse_diff('\n') == []
 
     # Diff with only new file (no old file)
     diff_new_only = """--- /dev/null
 +++ b/only_new.txt
 @@ -0,0 +1 @@
-+only new
-"""
-    files = parse_diff_files(diff_new_only)
-    assert files == []  /dev/null is ignored
++only new"""
+    files = parse_diff(diff_new_only)
+    assert files == ['only_new.txt']
 
     # Invalid diff format (should still handle gracefully)
     diff_invalid = "invalid diff string"
-    files = parse_diff_files(diff_invalid)
-    assert files == []  # No valid file paths found
+    files = parse_diff(diff_invalid)
+    assert files == [] # No valid file paths found
 
-
-@pytest.fixture
-def temp_git_repo():
-    """Create a temporary git repository for testing apply_diff."""
-    temp_dir = tempfile.mkdtemp()
-    repo = git.Repo.init(temp_dir)
-    # Make an initial commit to have a clean state
-    init_file = os.path.join(temp_dir, 'README.md')
-    with open(init_file, 'w') as f:
-        f.write('Initial commit content')
-    repo.git.add('README.md')
-    repo.git.commit('-m', 'initial commit')
-    yield temp_dir, repo
-    # Cleanup after test
-    shutil.rmtree(temp_dir, ignore_errors=True)
-
-
-def test_apply_diff_new_file(temp_git_repo):
+def test_apply_diff_new_file():
     """Test applying a diff that creates a new file."""
-    temp_dir, repo = temp_git_repo
-    diff = """--- /dev/null
+    with tempfile.TemporaryDirectory() as temp_dir:
+        diff = """--- /dev/null
 +++ b/test_new.txt
 @@ -0,0 +1 @@
-+This is a newly created file.
-"""
-    result = apply_diff(diff, temp_dir)
-    assert result['success'] == True
-    assert 'test_new.txt' in result['applied_files']
-    new_file_path = os.path.join(temp_dir, 'test_new.txt')
-    assert os.path.exists(new_file_path)
-    with open(new_file_path, 'r') as f:
-        content = f.read()
-    assert content.strip() == 'This is a newly created file.'
++This is a newly created file."""
 
+        result = apply_diff(diff, temp_dir)
+        assert result['success'] == True
+        assert 'test_new.txt' in result['applied_files']
 
-def test_apply_diff_modify_existing_file(temp_git_repo):
+        new_file_path = os.path.join(temp_dir, 'test_new.txt')
+        assert os.path.exists(new_file_path)
+        with open(new_file_path, 'r') as f:
+            content = f.read()
+        # 修复断言，strip()会去掉行末的换行符，使内容匹配
+        assert content.strip() == 'This is a newly created file.'
+
+def test_apply_diff_modify_existing_file():
     """Test applying a diff that modifies an existing file."""
-    temp_dir, repo = temp_git_repo
-    # Create an existing file and commit it
-    existing_file = os.path.join(temp_dir, 'existing.txt')
-    with open(existing_file, 'w') as f:
-        f.write('Original line 1\nOriginal line 2')
-    repo.git.add('existing.txt')
-    repo.git.commit('-m', 'add existing file')
+    with tempfile.TemporaryDirectory() as temp_dir:
+        # Create an existing file
+        existing_file = os.path.join(temp_dir, 'existing.txt')
+        with open(existing_file, 'w') as f:
+            f.write('Original line 1\nOriginal line 2\n')
 
-    diff = """--- a/existing.txt
+        diff = """--- a/existing.txt
 +++ b/existing.txt
 @@ -1,2 +1,2 @@
 -Original line 1
 +Modified line 1
- Original line 2
-"""
-    result = apply_diff(diff, temp_dir)
-    assert result['success'] == True
-    assert 'existing.txt' in result['applied_files']
-    with open(existing_file, 'r') as f:
-        content = f.read()
-    assert content == 'Modified line 1\nOriginal line 2'
+ Original line 2"""
 
+        result = apply_diff(diff, temp_dir)
+        assert result['success'] == True
+        assert 'existing.txt' in result['applied_files']
 
-def test_apply_diff_conflict_handling(temp_git_repo):
-    """Test applying a diff that causes a conflict with uncommitted changes."""
-    temp_dir, repo = temp_git_repo
-    # Create and commit a file
-    conflict_file = os.path.join(temp_dir, 'conflict.txt')
-    with open(conflict_file, 'w') as f:
-        f.write('Initial line 1\nInitial line 2')
-    repo.git.add('conflict.txt')
-    repo.git.commit('-m', 'add conflict file')
+        with open(existing_file, 'r') as f:
+            content = f.read()
+        assert content == 'Modified line 1\nOriginal line 2\n'
 
-    # Modify the file without committing to create conflict
-    with open(conflict_file, 'w') as f:
-        f.write('Changed line 1\nInitial line 2')  # Change first line
+def test_apply_diff_conflict_handling():
+    """Test applying a diff that causes a conflict because the source doesn't match."""
+    with tempfile.TemporaryDirectory() as temp_dir:
+        # Create a file with specific content
+        conflict_file = os.path.join(temp_dir, 'conflict.txt')
+        with open(conflict_file, 'w') as f:
+            f.write('Different line 1\nOriginal line 2\n') # This is different from what diff expects
 
-    diff = """--- a/conflict.txt
+        # This diff expects 'Initial line 1' but finds 'Different line 1'
+        diff = """--- a/conflict.txt
 +++ b/conflict.txt
 @@ -1,2 +1,2 @@
 -Initial line 1
 +Diff line 1
- Initial line 2
-"""
-    result = apply_diff(diff, temp_dir)
-    assert result['success'] == False
-    # Check for conflict or error in message
-    assert 'conflict' in result['message'].lower() or 'error' in result['message'].lower()
-    assert result['error_details'] != ''
+ Initial line 2"""
 
+        result = apply_diff(diff, temp_dir)
+        assert result['success'] == False # Should fail due to mismatch
+        # Check for conflict or error in message
+        assert 'error' in result['message'].lower() or 'does not match' in result['message'].lower()
+        assert result['error_details'] != ''
 
 def test_apply_diff_empty_diff():
     """Test applying an empty diff string."""
@@ -154,7 +125,6 @@ def test_apply_diff_empty_diff():
     assert result['success'] == False
     assert 'empty' in result['message'].lower()
 
-
 def test_apply_diff_invalid_directory():
     """Test applying a diff to a non-existent directory."""
     non_existent_dir = '/tmp/non_existent_dir_12345'
@@ -162,36 +132,33 @@ def test_apply_diff_invalid_directory():
 +++ b/dummy.txt
 @@ -1 +1 @@
 -old
-+new
-"""
++new"""
+
     result = apply_diff(diff, non_existent_dir)
     assert result['success'] == False
     assert 'does not exist' in result['message'].lower()
 
-
 def test_apply_diff_no_git_repo_initialization():
-    """Test applying a diff to a non-git directory, which should initialize a repo."""
-    temp_dir = tempfile.mkdtemp()
-    try:
+    """Test applying a diff to a non-git directory. This test is now redundant as there's no git dependency."""
+    with tempfile.TemporaryDirectory() as temp_dir:
         # Create a non-git directory with a file
         non_git_file = os.path.join(temp_dir, 'non_git.txt')
         with open(non_git_file, 'w') as f:
-            f.write('Pre-existing content')
+            f.write('Pre-existing content\n')
 
         diff = """--- a/non_git.txt
 +++ b/non_git.txt
 @@ -1 +1 @@
 -Pre-existing content
-+Updated content
-"""
++Updated content"""
+
         result = apply_diff(diff, temp_dir)
         assert result['success'] == True
         assert 'non_git.txt' in result['applied_files']
+
         with open(non_git_file, 'r') as f:
             content = f.read()
-        assert content == 'Updated content'
-    finally:
-        shutil.rmtree(temp_dir, ignore_errors=True)
+        assert content == 'Updated content\n'
 
 
 if __name__ == "__main__":