codeguard-perl

Perl Codeguard Gate

Goal: turn "looks fine" into repeatable tool evidence, and honestly distinguish pass, fail, unable to verify, and planned.

30-second start

1. At the repository root, confirm that 无专用标记文件 or the target file exists.
2. Probe tools:perlcritic --version。
3. First do a read-only check:perlcritic .。
4. Classify results as: code violations, missing configuration, missing tools, tool internal errors.
5. Only perform safely fixable items:perltidy -b '{file}'。
6. Re-run lint, and run the project's existing test/build gates.

You can directly ask:

• "Check this Perl project, don't modify anything first, and give me a classification of lint failures."
• "Only fix Perl formatting issues; list semantic issues first."
• "Verify Perl lint, test, and build evidence before committing."

Capability boundaries

✅ Good at handling

1. Based on .pl, .pm, .t and project markers to identify the Perl workspace.
2. Run perlcritic '{file}' and preserve exit codes, scope, and tool versions.
3. Distinguish formatting, static rules, configuration, dependency, and environment failures.
4. Use perltidy -b '{file}' to handle reversible issues and rescan.
5. Report local results in layers with CI/build/test evidence.

⚠️ Requires conditions

1. The target tool must be installed and its version compatible with project constraints.
2. It must be executed from the correct repository or module root.
3. If the project has custom configuration, the committed configuration prevails.
4. Whether generated code, vendor, and cache directories are scanned must follow repository rules.

❌ Not applicable

1. Do not treat formatter passing as compilation, test, or security audit passing.
2. Do not silently install tools, upgrade dependencies, or modify team rules.
3. Do not use suppress/ignore/raising thresholds to mask real problems.
4. Do not claim "check passed" when tools or configuration are missing.

When to use

• The user requests checking or fixing Perl code standards.
• AI modified .pl, .pm, .t, requiring pre-commit verification.
• CI shows failures related to perlcritic '{file}' .
• Need to determine whether a problem can be fixed automatically or must be handled manually.

When not to use

• The main task is learning language syntax, framework design, or business modeling, so the corresponding language professional skill should be used instead.
• The main task is dependency vulnerabilities, security audits, or license governance, so specialized security skills should be used.
• When the user only asks to explain one error and there is no project context, first give a local explanation and do not claim the repository is all green.

Data and security

This skill does not collect, upload, send, or store user code and credentials. By default it only reads local repository configuration and runs local tools; it does not install dependencies over the network, and does not record tokens, passwords, or private source code. Before any automatic fix, check the diff first; destructive or large-scale changes must be explicitly confirmed by the user.

Execution Contract

Project	Current Facts
Status	stable(since Codeguard V0.5)
File Extensions	.pl, .pm, .t
Project Marker	No dedicated marker file
Integration Configuration	Based on the repository's existing configuration
Tool Preparation	cpanm Perl::Critic Perl::Tidy
Probe Command	使用命令查找与项目配置检查
lint	perlcritic '{file}'
format/fix	perltidy -b '{file}'
Project-level gate	perlcritic .

Standard Workflow

Step 1: Determine the Real Scope

Confirm the repository root, module roots, generated directories, vendor directories, and user-specified files. For multi-module projects, first list the modules to be scanned; do not guess based on the current directory.

Step 2: Read the Project Contract

Read the actual commands in the repository's existing configuration and CI. The repository configuration takes precedence over this skill's examples; if the two conflict, report the difference first.

Step 3: Probe Tools and Versions

Run 对应工具 --version. Missing tools, incompatible versions, or configurations that fail to load are all recorded as "unable to verify," not as a pass.

Step 4: Run Read-Only Checks

Run perlcritic ., recording the command, working directory, exit code, tool version, and the first actionable error.

Step 5: Failure Classification

Type	Typical Signal	Handling
Formatting	Indentation, whitespace, import order	Formatter allowed, then check the diff
Static Rules	unused, complexity, naming, dangerous APIs	Minimal semantic fixes; no bulk guessing
Configuration	parser/config/schema not found	Fix the integration or report prerequisites
Environment	command not found, version conflicts	Report installation/version requirements; do not install silently
Tool Internal Errors	crash, timeout, parser exceptions	Preserve the raw evidence and narrow the reproduction scope

Step 6: Controlled Fixes

Prefer running perltidy -b '{file}'. Only handle issues that are certain and reversible; dependency upgrades, rule exemptions, generated files, and business semantic changes must be explained separately.

Step 7: Verification Loop

Re-run the same lint command, then run the project's existing tests and build. Only write "pass" when the command, scope, and exit code are all clear; otherwise write "not run" or "unable to verify."

Rules

1. Re-verify with the Same Command: After fixing, you must re-run the original command that triggered the failure.
2. Layered Evidence: Report lint, format, compile, test, and security separately.
3. Minimal Changes: Do not refactor along the way, and do not expand a style fix into a business rewrite.
4. Configuration Takes Precedence: Do not override the project's existing ignore, dialect, target, or version constraints.
5. No Fabrication: Tools not run, configurations not seen, and platforms not verified must be clearly marked.

Output Template

Perl Codeguard 结果
- 范围：<仓库/模块/文件>
- 工具：<名称与版本>
- 命令：<实际命令>
- 状态：PASS / FAIL / UNVERIFIED / PLANNED
- 发现：<按格式/规则/配置/环境分类>
- 修改：<文件与原因；无修改写 none>
- 复验：<命令、退出码>
- 未验证：<测试/构建/平台差异>

Gotchas

1. Missing tools are not a pass — must output UNVERIFIED and a clear preparation method.
2. formatter is not linter — All-green formatting cannot override static rules or compilation errors.
3. Root directory determines the result — Running in the wrong module may miss issues or load the wrong configuration.
4. Placeholders are not literal arguments — {file} must be replaced with real, authorized paths.
5. Automatic fixes may expand the diff — After fixing, review the diff first, then run the regression gate.
6. Generated and vendor directories require an explicit policy — Do not scan or modify third-party content across the whole repository at will.

Domain pitfalls and fixes

1. Domain pitfalls — The Perl::Critic profile determines severity levels; you must read the project .perlcriticrc。

When information is insufficient

Do not just say "please provide more information." First give a safe read-only inspection plan, and list the specific items that still need confirmation:

1. Repository/module root directory;
2. Target tool and version;
3. Project configuration files;
4. The authoritative command in CI;
5. Whether automatic fixes are allowed.

FAQ

Q1: If the tool is not installed, can we conclude the code is fine? No. The status must be UNVERIFIED。

Q2: Can ignore or suppression be added automatically? No. Exemptions may only be granted when the user explicitly accepts them and the reason is documented.

Q3: Why does it still fail after formatting? The formatter only covers formatting; static rules, configuration, compilation, and tests still need to be handled separately.

Q4: Should generated code be scanned? By default, follow the repository configuration; if there are no rules, first exclude generated/vendor content, then explain to the user.

Q5: How can I avoid changing too much at once? First fix in batches by failure category and file, and for each batch rerun the original command and review the diff.

Q6: If it passes locally, can I say CI will pass? No. You also need to align CI's versions, environment variables, operating system, and command scope.

Load resources on demand

• When encountering exit codes, failure classification, or exemption decisions, read references/rules/gate-rules.md。
• When you need to verify this language's registry, toolchain, and project configuration, read references/tooling/toolchain.md。
• When you need copyable task examples, read by scenario examples/, there is no need to load all of them at once.