fix: respect specified paths in git repository

[jhult]

Summary

• Fixed header check/fix commands to respect specified file paths even when in a git repository
• Previously, specifying paths in a git repo would incorrectly check all tracked files instead of just the specified paths
• Now supports individual files, directories, and glob patterns correctly in all contexts

Changes

• Added matchPaths() function in pkg/header/check.go to filter files using glob pattern matching
• Updated listFiles() to respect configured paths when in git repositories
• Updated help text for header check and header fix commands to clarify accepted path types
• Added TestMatchPaths() to verify pattern matching behavior

Testing

• All existing tests pass
• New TestMatchPaths() validates exact file matches, glob patterns, and double-star patterns
• Verified behavior with single files, multiple files, and glob patterns in git repositories

[Copilot]

Pull request overview

This PR fixes an issue where specifying file paths in a git repository would incorrectly check all tracked files instead of just the specified paths. The changes add a matchPaths() function to filter git candidates using glob pattern matching and update command help text to clarify supported path types.

Changes:

• Added matchPaths() function to filter files by glob patterns
• Modified listFiles() to respect configured paths when in git repositories
• Updated help text for header check and header fix commands
• Added test coverage for the new pattern matching logic

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 3 comments.

File	Description
pkg/header/check.go	Added matchPaths() function and integrated it into listFiles() to filter git candidates
pkg/header/check_test.go	Added TestMatchPaths() to validate pattern matching behavior
commands/header_check.go	Updated command help text to document accepted path types
commands/header_fix.go	Updated command help text to document accepted path types

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[Copilot]

This test case expects that a directory pattern "pkg/header/" should NOT match the file "pkg/header/check.go". However, this is inconsistent with the existing tryMatchPatten function in pkg/header/config.go (lines 132-153), which includes logic to match files within a specified directory.

In the non-git code path, when a user specifies "pkg/header/" as a path, doublestar.Glob expands it to the directory, and walkFile recursively finds all files within it. For consistency, the git code path should behave the same way - files within "pkg/header/" should match the pattern "pkg/header/".

This test case should expect true, not false, and the matchPaths function should be updated to include directory prefix matching logic similar to tryMatchPatten.

Suggested change

	expected: false,
	expected: true,

[Copilot]

The matchPaths function doesn't handle directory patterns consistently with the existing tryMatchPatten function in config.go. When a user specifies a directory pattern like "pkg/header/", it should match files within that directory (e.g., "pkg/header/check.go"), but the current implementation using only doublestar.Match will return false.

The tryMatchPatten function (lines 132-153 in pkg/header/config.go) includes additional logic after doublestar.Match to handle directory patterns by checking if the file path has the pattern as a prefix. This same logic should be included in matchPaths to ensure consistent behavior between git and non-git repositories.

Without this, users who specify directory paths (with or without trailing slashes) will get different behavior in git vs non-git repositories.

Suggested change

	}
	}
	// Fallback for directory patterns (e.g., "pkg/header/" or "pkg/header")
	// to behave consistently with tryMatchPatten in config.go.
	if err == nil {
	dirPattern := pattern
	// Ensure the pattern ends with a path separator so it clearly denotes a directory.
	if !strings.HasSuffix(dirPattern, "/") && !strings.HasSuffix(dirPattern, string(os.PathSeparator)) {
	dirPattern = dirPattern + "/"
	}
	// Normalize both paths to use '/' so prefix matching is consistent across platforms.
	normalizedDir := strings.ReplaceAll(dirPattern, "\\", "/")
	normalizedFile := strings.ReplaceAll(file, "\\", "/")
	if strings.HasPrefix(normalizedFile, normalizedDir) {
	return true
	}
	}

[Copilot]

The updated documentation states that the fix command "Accepts files, directories, and glob patterns" when command-line paths are provided. However, the implementation (lines 40-46, not shown in this diff) doesn't actually support directories or glob patterns when args are provided - it only passes the args directly to header.Fix which expects individual file paths.

This documentation is misleading. Either the implementation needs to be updated to support directories and glob patterns (similar to how check command handles args by setting h.Paths = args), or the documentation should clarify that directories and glob patterns are only supported through the config file, not command-line arguments.

[kezhenxu94]

Hi, I think when we pass the paths to the CLI args we intend to check that files regardless of the config file. The args here should be highest priority even if they are not configured in config file