datawhalechina/hello-agents · warning · PatchApplyError

Patch too large: {total_changed} changed lines > {self.max_t

Error message

Patch too large: {total_changed} changed lines > {self.max_total_changed_lines}

What it means

PatchApplyError raised when the estimated total changed lines across all operations exceeds max_total_changed_lines. Like the file-count limit, it is a pre-execution size guardrail: nothing is written, so the working tree stays untouched.

Source

Thrown at Co-creation-projects/YYHDBL-HelloCodeAgentCli/code_agent/executors/apply_patch_executor.py:121

            
        返回:
            ApplyResult: 包含被修改文件和备份文件信息的结果对象
            
        异常:
            PatchApplyError: 当补丁不符合格式、超出限制或应用失败时抛出
        """
        # 解析补丁文本，提取操作列表
        ops = self._parse_patch(patch_text)
        
        # 统计受影响的文件数量，检查是否超过限制
        touched_files = [op[1] for op in ops if op[0] in {"add", "update", "delete"}]
        if len(set(touched_files)) > self.max_files:
            raise PatchApplyError(f"Too many files in patch: {len(set(touched_files))} > {self.max_files}")

        # 估算补丁修改的总行数，检查是否超过限制
        total_changed = self._estimate_changed_lines(ops)
        if total_changed > self.max_total_changed_lines:
            raise PatchApplyError(f"Patch too large: {total_changed} changed lines > {self.max_total_changed_lines}")

        # 创建本次补丁应用的专属备份目录（时间戳命名）
        backup_run_dir = self.backups_dir / datetime.now().strftime("%Y%m%d_%H%M%S")
        backup_run_dir.mkdir(parents=True, exist_ok=True)

        # 初始化结果收集变量
        files_changed: List[str] = []  # 记录被修改的文件路径
        backups: List[str] = []  # 记录创建的备份文件路径

        # 遍历所有解析出的操作，逐个执行
        for kind, rel_path, payload in ops:
            # 安全检查：确保路径在仓库内，防止路径遍历攻击
            target = self._safe_path(rel_path)
            
            # 安全检查：确保文件后缀在允许的列表中
            self._enforce_suffix(target)

            if kind == "add":

View on GitHub (pinned to 606a07d341)

Solutions

Break the change into sequential patches below the line budget (apply incrementally).
Reduce patch noise: drop unrelated formatting/hunk churn from the payload.
If legitimate, raise max_total_changed_lines in the executor configuration.
The message reports the estimated count so you can size the chunks.

Example fix

# before
executor.apply(huge_patch)  # 5000 changed lines > 3000 cap

# after
for part in split_patch_by_lines(huge_patch, max_lines=executor.max_total_changed_lines):
    executor.apply(part)

Defensive patterns

Strategy: validation

Validate before calling

estimated = estimate_changed_lines(parse_patch(patch_text))
assert estimated <= executor.max_total_changed_lines, \
    f"patch too large ({estimated} lines); split it"

Try / catch

try:
    executor.apply(patch_text)
except PatchApplyError as e:
    if str(e).startswith("Patch too large"):
        for part in split_patch_by_lines(patch_text, executor.max_total_changed_lines):
            executor.apply(part)
    else:
        raise

Prevention

Budget patch size client-side using the same line-estimate rule as the executor.
Split big file additions into staged patches applied sequentially.
Keep unrelated formatting churn out of patches to stay under the cap.

When it happens

Trigger: A patch whose estimated changed-line total (per _estimate_changed_lines over add/update/delete payloads) exceeds the configured cap — e.g. a single Add File with a very long payload.

Common situations: Agent generating a whole new large file in one patch; squashing many edits into one update; threshold tuned down after workflows depended on bigger patches.

Related errors

AI-assisted analysis of datawhalechina/hello-agents@606a07d341 (2026-08-14). Data as JSON: /api/errors/6ece51d1a3bd38c6. Report an issue: GitHub.