The Files Filter allows you to apply rules only when specific files are modified in a pull request. This is useful for creating targeted rules that apply only to certain parts of your codebase.

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Configuration

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type
string
required
Must be set to "files"
​
added
object
Conditions for added files
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added.match
string | string[]
File patterns that should match for added files
​
added.ignore
string | string[]
File patterns that should not match for added files
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modified
object
Conditions for modified files
​
modified.match
string | string[]
File patterns that should match for modified files
​
modified.ignore
string | string[]
File patterns that should not match for modified files

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Basic Usage

if:
  - type: "files"
    modified:
      match: "src/frontend/.*"

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Examples

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Match Specific Files

Apply a rule Apply a rule only when specific files are modified: 
if:
  - type: "files"
    modified:
      match: "package.json"

​
Match File Types

Apply a rule based on file types: 
if:
  - type: "files"
    modified:
      match: ".*\\.(js|ts|tsx)$"

​
Match Files in Directory

Apply a rule only when files in a specific directory are changed: 
if:
  - type: "files"
    modified:
      match: "src/components/.*"

​
Ignore Certain Files

Apply a rule only when meaningful files are changed (ignoring configuration files): 
if:
  - type: "files"
    modified:
      match: "src/.*"
      ignore: [".*\\.config.js", "package-lock.json"]

​
Added Files Only

Apply a rule only when new files are added: 
if:
  - type: "files"
    added:
      match: "src/.*"

​
Pattern Matching

The Files Filter supports several pattern matching methods:
  1. Exact match: "package.json"
  2. Glob patterns: "src/**/*.js"
  3. Regular expressions: "/^src\/.*\.jsx?$/" (enclosed in forward slashes)

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How It Works

1

Get Changed Files

The filter retrieves all files changed in the PR, categorized by change type (added, modified, deleted)
2

Process Added Files

If added conditions are specified, it checks if added files match the required patterns
3

Process Modified Files

If modified conditions are specified, it checks if modified files match the required patterns
4

Determine Match

Returns a match result indicating whether the specified file patterns were found

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Practical Use Cases

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Component-Specific Rules

Apply different rules based on the type of components changed: 
ruleset:
  - name: "Frontend Tests Required"
    when:
      - "pull_request.opened"
      - "pull_request.synchronize"
    if:
      - type: "files"
        modified:
          match: "src/components/.*\\.(js|tsx)$"
    validate:
      - type: "dependent"
        files:
          - when: "src/components/(.+)\\.(js|tsx)$"
            require: "src/components/$1.test.(js|tsx)"
    on_failure:
      - comment:
          body: "Frontend component changes require corresponding test files"

  - name: "API Documentation"
    when:
      - "pull_request.opened"
      - "pull_request.synchronize"
    if:
      - type: "files"
        modified:
          match: "src/api/.*"
    validate:
      - type: "dependent"
        files:
          - when: "src/api/(.+)\\.js$"
            require: "docs/api/$1.md"
    on_failure:
      - comment:
          body: "API changes require updated documentation"

​
Security Review for Sensitive Files

Require special handling for security-sensitive changes: 
ruleset:
  - name: "Security Review"
    when:
      - "pull_request.opened"
      - "pull_request.synchronize"
    if:
      - type: "files"
        modified:
          match: ["src/auth/.*", "src/crypto/.*", "config/security\\..*"]
    on_success:
      - label:
          add: ["security-review-required"]
      - requestReview:
          reviewers: ["security-team-lead"]
      - comment:
          body: |
            This PR modifies security-sensitive files and requires a security review.

            @security-team-lead has been automatically requested as a reviewer.

​
Different Requirements by File Type

Apply different validation rules based on file type: 
ruleset:
  - name: "JavaScript Style"
    when:
      - "pull_request.opened"
      - "pull_request.synchronize"
    if:
      - type: "files"
        modified:
          match: ".*\\.js$"
    validate:
      - type: "dependent"
        files:
          - when: ".*\\.js$"
            require: ".eslintrc.js"

  - name: "CSS Style"
    when:
      - "pull_request.opened"
      - "pull_request.synchronize"
    if:
      - type: "files"
        modified:
          match: ".*\\.css$"
    validate:
      - type: "dependent"
        files:
          - when: ".*\\.css$"
            require: ".stylelintrc"

​
Automatic Labeling

Automatically label PRs based on changed files: 
ruleset:
  - name: "Frontend Label"
    when:
      - "pull_request.opened"
      - "pull_request.synchronize"
    if:
      - type: "files"
        modified:
          match: "src/frontend/.*"
    on_success:
      - label:
          add: ["frontend"]

  - name: "Backend Label"
    when:
      - "pull_request.opened"
      - "pull_request.synchronize"
    if:
      - type: "files"
        modified:
          match: "src/backend/.*"
    on_success:
      - label:
          add: ["backend"]

  - name: "Documentation Label"
    when:
      - "pull_request.opened"
      - "pull_request.synchronize"
    if:
      - type: "files"
        modified:
          match: ["docs/.*", "README\\.md"]
    on_success:
      - label:
          add: ["documentation"]

​
Best Practices

Use specific patterns to target exactly the files you care about
Group related file patterns for clarity
Consider using the ignore patterns to exclude non-substantive changes
Test your patterns to ensure they match as expected
Overly complex patterns can be difficult to maintain; keep them as simple as possible

​
Pattern Examples

Here are some common pattern examples:
PatternMatches
src/.*All files in the src directory and subdirectories
.*\\.js$All JavaScript files
.*\\.(js|ts)$All JavaScript and TypeScript files
src/components/.*All files in src/components and subdirectories
package\\.jsonOnly the root package.json file
/^docs\/api\/.*\.md$/Markdown files in the docs/api directory