v2.4.0 - support local execution with act + allow tags (#40 )

* Avoid code repetition with exec() and output listeners * Improve behavior for new branches and when it's running in ACT * Detect parent commit only if needed * Fix parent commit detection for initial commit * Improve logging * Improve current ref detection * Fix issue when base is a already fetched tag * Fix issue when base is a already fetched tag * Update README * Document usage with act * Use `git log` to get changes in latest commit * Disable other output for `git log` * get short name from base ref + improve loggig * update CHANGELOG
Small improvement to project description
2025-12-23 23:48:20 +00:00 · 2020-09-30 00:32:49 +02:00 · 2020-09-14 18:49:18 +02:00 · 2020-09-14 18:09:37 +02:00 · 2020-09-14 17:26:56 +02:00 · 2020-09-14 17:22:51 +02:00
23 changed files with 1865 additions and 423 deletions
--- a/.editorconfig
+++ b/.editorconfig
@@ -0,0 +1,9 @@
+root = true
+
+[*]
+charset = utf-8
+end_of_line = lf
+insert_final_newline = true
+trim_trailing_whitespace = true
+indent_style = space
+indent_size = 2
--- a/.eslintrc.json
+++ b/.eslintrc.json
@@ -25,7 +25,7 @@
      "@typescript-eslint/generic-type-naming": ["error", "^[A-Z][A-Za-z]*$"],
      "@typescript-eslint/no-array-constructor": "error",
      "@typescript-eslint/no-empty-interface": "error",
-      "@typescript-eslint/no-explicit-any": "error",
+      "@typescript-eslint/no-explicit-any": "off",
      "@typescript-eslint/no-extraneous-class": "error",
      "@typescript-eslint/no-for-in-array": "error",
      "@typescript-eslint/no-inferrable-types": "error",
@@ -42,7 +42,7 @@
      "@typescript-eslint/prefer-includes": "error",
      "@typescript-eslint/prefer-interface": "error",
      "@typescript-eslint/prefer-string-starts-ends-with": "error",
-      "@typescript-eslint/promise-function-async": "error",
+      "@typescript-eslint/promise-function-async": ["error", { "allowAny": true }],
      "@typescript-eslint/require-array-sort-compare": "error",
      "@typescript-eslint/restrict-plus-operands": "error",
      "semi": "off",
--- a/.gitattributes
+++ b/.gitattributes
@@ -0,0 +1 @@
+* text=auto eol=lf
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -12,3 +12,15 @@ jobs:
    - run: |
        npm install
        npm run all
+
+  self-test:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - uses: ./
+      id: filter
+      with:
+        filters: '.github/filters.yml'
+    - name: filter-test
+      if: steps.filter.outputs.any != 'true' || steps.filter.outputs.error == 'true'
+      run: exit 1
--- a/.github/workflows/pull-request-verification.yml
+++ b/.github/workflows/pull-request-verification.yml
@@ -1,11 +1,9 @@
 name: "Pull Request Verification"
 on:
  pull_request:
-    types:
-      - opened
-      - synchronize
    branches:
      - master
+      - develop

 jobs:
  build:
@@ -56,3 +54,63 @@ jobs:
    - name: filter-test
      if: steps.filter.outputs.any != 'true' || steps.filter.outputs.error == 'true'
      run: exit 1
+
+  test-wd-without-token:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+      with:
+        path: somewhere
+    - uses: ./somewhere
+      id: filter
+      with:
+        token: ''
+        working-directory: somewhere
+        filters: '.github/filters.yml'
+    - name: filter-test
+      if: steps.filter.outputs.any != 'true' || steps.filter.outputs.error == 'true'
+      run: exit 1
+
+  test-change-type:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: configure GIT user
+      run: git config user.email "john@nowhere.local" && git config user.name "John Doe"
+    - name: modify working tree
+      run: touch add.txt && rm README.md && echo "TEST" > LICENSE
+    - name: commit changes
+      run: git add -A && git commit -a -m 'testing this action'
+    - uses: ./
+      id: filter
+      with:
+        token: ''
+        list-files: shell
+        filters: |
+          added:
+            - added: "add.txt"
+          deleted:
+            - deleted: "README.md"
+          modified:
+            - modified: "LICENSE"
+          any:
+            - added|deleted|modified: "*"
+    - name: Print 'added_files'
+      run: echo ${{steps.filter.outputs.added_files}}
+    - name: Print 'modified_files'
+      run: echo ${{steps.filter.outputs.modified_files}}
+    - name: Print 'deleted_files'
+      run: echo ${{steps.filter.outputs.deleted_files}}
+    - name: filter-test
+      # only single quotes are supported in GH action literal
+      # single quote needs to be escaped with single quote
+      # '''add.txt''' resolves to string 'add.txt'
+      if: |
+        steps.filter.outputs.added != 'true'
+        || steps.filter.outputs.deleted != 'true'
+        || steps.filter.outputs.modified != 'true'
+        || steps.filter.outputs.any != 'true'
+        || steps.filter.outputs.added_files != '''add.txt'''
+        || steps.filter.outputs.modified_files != '''LICENSE'''
+        || steps.filter.outputs.deleted_files != '''README.md'''
+      run: exit 1
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -0,0 +1,39 @@
+# Changelog
+
+## v2.4.0
+- [Support pushes of tags or when tag is used as base](https://github.com/dorny/paths-filter/pull/40)
+- [Use git log to detect changes from PRs merge commit if token is not available](https://github.com/dorny/paths-filter/pull/40)
+- [Support local execution with act](https://github.com/dorny/paths-filter/pull/40)
+- [Improved processing of repository initial push](https://github.com/dorny/paths-filter/pull/40)
+- [Improved processing of first push of new branch](https://github.com/dorny/paths-filter/pull/40)
+
+
+## v2.3.0
+- [Improved documentation](https://github.com/dorny/paths-filter/pull/37)
+- [Change detection using git "three dot" diff](https://github.com/dorny/paths-filter/pull/35)
+- [Export files matching filter](https://github.com/dorny/paths-filter/pull/32)
+- [Extend filter syntax with optional specification of file status: add, modified, deleted](https://github.com/dorny/paths-filter/pull/22)
+- [Add working-directory input](https://github.com/dorny/paths-filter/pull/21)
+
+## v2.2.1
+- [Add support for pull_request_target](https://github.com/dorny/paths-filter/pull/29)
+
+## v2.2.0
+- [Improve change detection for feature branches](https://github.com/dorny/paths-filter/pull/16)
+
+## v2.1.0
+- [Support reusable paths blocks with yaml anchors](https://github.com/dorny/paths-filter/pull/13)
+
+## v2.0.0
+- [Added support for workflows triggered by push events](https://github.com/dorny/paths-filter/pull/10)
+- Action and repository renamed to paths-filter - original name doesn't make sense anymore
+
+## v1.1.0
+- [Allows filters to be specified in own .yml file](https://github.com/dorny/paths-filter/pull/8)
+- [Adds alternative change detection using git fetch and git diff-index](https://github.com/dorny/paths-filter/pull/9)
+
+## v1.0.1
+Updated dependencies - fixes github security alert
+
+## v1.0.0
+First official release uploaded to marketplace.
--- a/2
+++ b/2
@@ -1,7 +1,7 @@

 The MIT License (MIT)

-Copyright (c) 2018 GitHub, Inc. and contributors
+Copyright (c) 2020 Michal Dorner and contributors

 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
--- a/README.md
+++ b/README.md
@@ -1,72 +1,155 @@
-<p align="center">
-  <a href="https://github.com/dorny/pr-changed-files-filter/actions"><img alt="typescript-action status" src="https://github.com/dorny/pr-changed-files-filter/workflows/Build/badge.svg"></a>
-</p>

-**CAUTION**: This action can be only used in a workflow triggered by `pull_request` event.
+# paths-filter

-# Pull request changed files filter
+This [Github Action](https://github.com/features/actions) enables conditional execution of workflow steps and jobs,
+based on the files modified by pull request, feature branch or in pushed commits.

-This [Github Action](https://github.com/features/actions) enables conditional execution of workflow job steps considering which files are modified by a pull request.
-
-It saves time and resources especially in monorepo setups, where you can run slow tasks (e.g. integration tests) only for changed components.
-Github workflows built-in
-[path filters](https://help.github.com/en/actions/referenceworkflow-syntax-for-github-actions#onpushpull_requestpaths)
+It saves time and resources especially in monorepo setups, where you can run slow tasks (e.g. integration tests or deployments) only for changed components.
+Github workflows built-in [path filters](https://docs.github.com/en/actions/reference/workflow-syntax-for-github-actions#onpushpull_requestpaths)
 doesn't allow this because they doesn't work on a level of individual jobs or steps.

-## Usage

-The action accepts filter rules in the YAML format.
-Each filter rule is a list of [glob expressions](https://github.com/isaacs/minimatch).
-Corresponding output variable will be created to indicate if there's a changed file matching any of the rule glob expressions.
-Output variables can be later used in the `if` clause to conditionally run specific steps.
-
-### Inputs
- **`token`**: GitHub Access Token - defaults to `${{ github.token }}`
- **`filters`**: Path to the configuration file or directly embedded string in YAML format. Filter configuration is a dictionary, where keys specifies rule names and values are lists of file path patterns.
-
-### Outputs
- For each rule it sets output variable named by the rule to text:
-   - `'true'` - if **any** of changed files matches any of rule patterns
-   - `'false'` - if **none** of changed files matches any of rule patterns
+## Supported workflows:
+- Pull requests:
+  - Action triggered by **[pull_request](https://docs.github.com/en/actions/reference/events-that-trigger-workflows#pull_request)**
+    or **[pull_request_target](https://docs.github.com/en/actions/reference/events-that-trigger-workflows#pull_request_target)** event
+  - Changes are detected against the pull request base branch
+  - Uses Github REST API to fetch list of modified files
+- Feature branches:
+  - Action triggered by **[push](https://docs.github.com/en/actions/reference/events-that-trigger-workflows#push)** event
+  - Changes are detected against the merge-base with configured base branch
+  - Uses git commands to detect changes - repository must be already [checked out](https://github.com/actions/checkout)
+- Master, Release or other long-lived branches:
+  - Action triggered by **[push](https://docs.github.com/en/actions/reference/events-that-trigger-workflows#push)** event
+  - Changes are detected against the most recent commit on the same branch before the push
+  - Uses git commands to detect changes - repository must be already [checked out](https://github.com/actions/checkout)


-### Notes
- minimatch [dot](https://www.npmjs.com/package/minimatch#dot) option is set to true - therefore
-  globbing will match also paths where file or folder name starts with a dot.
+## Important notes:
+- Paths expressions are evaluated using [minimatch](https://github.com/isaacs/minimatch) library.
+  Documentation for path expression format can be found on project github page.
+- Minimatch [dot](https://www.npmjs.com/package/minimatch#dot) option is set to true.
+  Globbing will match also paths where file or folder name starts with a dot.
+- It's recommended to quote your path expressions with `'` or `"`. Otherwise you will get an error if it starts with `*`.
+- Local execution with [act](https://github.com/nektos/act) works only with alternative runner image. Default runner doesn't have `git` binary.
+  - Use: `act -P ubuntu-latest=nektos/act-environments-ubuntu:18.04`
+
+
+# What's New
+- Support for tag pushes and tags as a base reference
+- Fixes for various edge cases when event payload is incomplete
+  - Supports local execution with [act](https://github.com/nektos/act)
+- Fixed behavior of feature branch workflow:
+  - Detects only changes introduced by feature branch. Later modifications on base branch are ignored.
+- Filter by type of file change:
+  - Optionally consider if file was added, modified or deleted
+- Custom processing of changed files:
+  - Optionally export paths of all files matching the filter
+  - Output can be space-delimited or in JSON format
+- Improved documentation and logging
+
+For more information see [CHANGELOG](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
+
+# Usage

-### Sample workflow
 ```yaml
-name: Build verification
+- uses: dorny/paths-filter@v2
+  with:
+    # Defines filters applied to detected changed files.
+    # Each filter has a name and list of rules.
+    # Rule is a glob expression - paths of all changed
+    # files are matched against it.
+    # Rule can optionally specify if the file
+    # should be added, modified or deleted.
+    # For each filter there will be corresponding output variable to
+    # indicate if there's a changed file matching any of the rules.
+    # Optionally there can be a second output variable
+    # set to list of all files matching the filter.
+    # Filters can be provided inline as a string (containing valid YAML document)
+    # or as a relative path to separate file (e.g.: .github/filters.yaml).
+    # Multiline string is evaluated as embedded filter definition,
+    # single line string is evaluated as relative path to separate file.
+    # Filters syntax is documented by example - see examples section.
+    filters: ''

-on:
-  pull_request:
-    types:
-      - opened
-      - synchronize
-    branches:
-      - master
+    # Branch or tag against which the changes will be detected.
+    # If it references same branch it was pushed to,
+    # changes are detected against the most recent commit before the push.
+    # Otherwise it uses git merge-base to find best common ancestor between
+    # current branch (HEAD) and base.
+    # When merge-base is found, it's used for change detection - only changes
+    # introduced by current branch are considered.
+    # All files are considered as added if there is no common ancestor with
+    # base branch or no previous commit.
+    # This option is ignored if action is triggered by pull_request event.
+    # Default: repository default branch (e.g. master)
+    base: ''
+
+    # How many commits are initially fetched from base branch.
+    # If needed, each subsequent fetch doubles the
+    # previously requested number of commits until the merge-base
+    # is found or there are no more commits in the history.
+    # This option takes effect only when changes are detected
+    # using git against base branch (feature branch workflow).
+    # Default: 20
+    initial-fetch-depth: ''
+
+    # Enables listing of files matching the filter:
+    #   'none'  - Disables listing of matching files (default).
+    #   'json'  - Matching files paths are formatted as JSON array.
+    #   'shell' - Matching files paths are escaped and space-delimited.
+    #             Output is usable as command line argument list in linux shell.
+    # Default: none
+    list-files: ''
+
+    # Relative path under $GITHUB_WORKSPACE where the repository was checked out.
+    working-directory: ''
+
+    # Personal access token used to fetch list of changed files
+    # from Github REST API.
+    # It's used only if action is triggered by pull request event.
+    # Github token from workflow context is used as default value.
+    # If empty string is provided, action falls back to detect
+    # changes using git commands.
+    # Default: ${{ github.token }}
+    token: ''
+```
+
+## Outputs
+- For each filter it sets output variable named by the filter to the text:
+   - `'true'` - if **any** of changed files matches any of filter rules
+   - `'false'` - if **none** of changed files matches any of filter rules
+- If enabled, for each filter it sets output variable with name `${FILTER_NAME}_files`. It will contain list of all files matching the filter.
+
+# Examples
+
+## Conditional execution
+
+<details>
+  <summary>Execute <b>step</b> in a workflow job only if some file in a subfolder is changed</summary>
+
+```yaml
 jobs:
  tests:
    runs-on: ubuntu-latest
    steps:
    - uses: actions/checkout@v2
-    - uses: dorny/pr-changed-files-filter@v1
+    - uses: dorny/paths-filter@v2
      id: filter
      with:
-        # inline YAML or path to separate file (e.g.: .github/filters.yaml)
        filters: |
          backend:
-            - 'backend/**/*'
+            - 'backend/**'
          frontend:
-            - 'frontend/**/*'
+            - 'frontend/**'

    # run only if 'backend' files were changed
-    - name: backend unit tests
+    - name: backend tests
      if: steps.filter.outputs.backend == 'true'
      run: ...

    # run only if 'frontend' files were changed
-    - name: frontend unit tests
+    - name: frontend tests
      if: steps.filter.outputs.frontend == 'true'
      run: ...

@@ -75,26 +158,233 @@ jobs:
      if: steps.filter.outputs.backend == 'true' || steps.filter.outputs.frontend == 'true'
      run: ...
 ```
+</details>

-## How it works
+<details>
+  <summary>Execute <b>job</b> in a workflow only if some file in a subfolder is changed</summary>

-1. Required inputs are checked (`filters`)
-2. If token was provided, it's used to fetch list of changed files from Github API.
-3. If token was not provided, base branch is fetched and changed files are detected using `git diff-index` command.
-4. For each filter rule it checks if there is any matching file
-5. Output variables are set
+```yml
+jobs:
+  # JOB to run change detection
+  changes:
+    runs-on: ubuntu-latest
+    # Set job outputs to values from filter step
+    outputs:
+      backend: ${{ steps.filter.outputs.backend }}
+      frontend: ${{ steps.filter.outputs.frontend }}
+    steps:
+    # For pull requests it's not necessary to checkout the code
+    - uses: dorny/paths-filter@v2
+      id: filter
+      with:
+        filters: |
+          backend:
+            - 'backend/**'
+          frontend:
+            - 'frontend/**'

-## Difference from related projects:
+  # JOB to build and test backend code
+  backend:
+    needs: changes
+    if: ${{ needs.changes.outputs.backend == 'true' }}
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - ...

- [Has Changed Path](https://github.com/MarceloPrado/has-changed-path)
-  - detects changes from previous commit
-  - you have to configure `checkout` action to fetch some number of previous commits
-  - `git diff` is used for change detection
-  - outputs only single `true` / `false` value if any of provided paths contains changes
- [Changed Files Exporter](https://github.com/futuratrepadeira/changed-files)
-  - outputs lists with paths of created, updated and deleted files
-  - output is not directly usable in the `if` clause
- [Changed File Filter](https://github.com/tony84727/changed-file-filter)
-  - allows change detection between any refs or commits
-  - fetches whole history of your git repository
-  - might have negative performance impact on big repositories (github by default fetches only single commit)
+  # JOB to build and test frontend code
+  frontend:
+    needs: changes
+    if: ${{ needs.changes.outputs.frontend == 'true' }}
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - ...
+```
+</details>
+
+## Change detection workflows
+
+<details>
+  <summary><b>Pull requests:</b> Detect changes against PR base branch</summary>
+
+```yaml
+on:
+  pull_request:
+    branches: # PRs to following branches will trigger the workflow
+      - master
+      - develop
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - uses: dorny/paths-filter@v2
+      id: filter
+      with:
+        filters: ... # Configure your filters
+```
+</details>
+
+<details>
+  <summary><b>Feature branch:</b> Detect changes against configured base branch</summary>
+
+```yaml
+on:
+  push:
+    branches: # Push to following branches will trigger the workflow
+      - feature/**
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+      with:
+        # This may save additional git fetch roundtrip if
+        # merge-base is found within latest 20 commits
+        fetch-depth: 20
+    - uses: dorny/paths-filter@v2
+      id: filter
+      with:
+        base: develop # Change detection against merge-base with this branch
+        filters: ... # Configure your filters
+```
+</details>
+
+<details>
+  <summary><b>Long lived branches:</b> Detect changes against the most recent commit on the same branch before the push</summary>
+
+```yaml
+on:
+  push:
+    branches: # Push to following branches will trigger the workflow
+      - master
+      - develop
+      - release/**
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - uses: dorny/paths-filter@v2
+      id: filter
+      with:
+        # Use context to get branch where commits were pushed.
+        # If there is only one long lived branch (e.g. master),
+        # you can specify it directly.
+        # If it's not configured, the repository default branch is used.
+        base: ${{ github.ref }}
+        filters: ... # Configure your filters
+```
+</details>
+
+## Advanced options
+
+<details>
+  <summary>Define filter rules in own file</summary>
+
+```yaml
+- uses: dorny/paths-filter@v2
+      id: filter
+      with:
+        # Path to file where filters are defined
+        filters: .github/filters.yaml
+```
+</details>
+
+<details>
+  <summary>Use YAML anchors to reuse path expression(s) inside another rule</summary>
+
+```yaml
+- uses: dorny/paths-filter@v2
+      id: filter
+      with:
+        # &shared is YAML anchor,
+        # *shared references previously defined anchor
+        # src filter will match any path under common, config and src folders
+        filters: |
+          shared: &shared
+            - common/**
+            - config/**
+          src:
+            - *shared
+            - src/**
+```
+</details>
+
+<details>
+  <summary>Consider if file was added, modified or deleted</summary>
+
+```yaml
+- uses: dorny/paths-filter@v2
+      id: filter
+      with:
+        # Changed file can be 'added', 'modified', or 'deleted'.
+        # By default the type of change is not considered.
+        # Optionally it's possible to specify it using nested
+        # dictionary, where type(s) of change composes the key.
+        # Multiple change types can be specified using `|` as delimiter.
+        filters: |
+          addedOrModified:
+            - added|modified: '**'
+          allChanges:
+            - added|deleted|modified: '**'
+```
+</details>
+
+
+## Custom processing of changed files
+
+<details>
+  <summary>Passing list of modified files as command line args in Linux shell</summary>
+
+```yaml
+- uses: dorny/paths-filter@v2
+  id: filter
+  with:
+    # Enable listing of files matching each filter.
+    # Paths to files will be available in `${FILTER_NAME}_files` output variable.
+    # Paths will be escaped and space-delimited.
+    # Output is usable as command line argument list in linux shell
+    list-files: shell
+
+    # In this example changed files will be checked by linter.
+    # It doesn't make sense to lint deleted files.
+    # Therefore we specify we are only interested in added or modified files.
+    filters: |
+      markdown:
+        - added|modified: '*.md'
+- name: Lint Markdown
+  if: ${{ steps.filter.outputs.markdown == 'true' }}
+  run: npx textlint ${{ steps.filter.outputs.markdown_files }}
+```
+</details>
+
+<details>
+  <summary>Passing list of modified files as JSON array to another action</summary>
+
+```yaml
+- uses: dorny/paths-filter@v2
+  id: filter
+  with:
+    # Enable listing of files matching each filter.
+    # Paths to files will be available in `${FILTER_NAME}_files` output variable.
+    # Paths will be formatted as JSON array
+    list-files: json
+
+    # In this example all changed files are passed to following action to do
+    # some custom processing.
+    filters: |
+      changed:
+        - '**'
+- name: Lint Markdown
+  uses: johndoe/some-action@v1
+  with:
+    files: ${{ steps.filter.changed_files }}
+```
+</details>
+
+
+# License
+
+The scripts and documentation in this project are released under the [MIT License](https://github.com/dorny/paths-filter/blob/master/LICENSE)
--- a/tests/filter.test.ts
+++ b/tests/filter.test.ts
@@ -0,0 +1,155 @@
+import {Filter} from '../src/filter'
+import {File, ChangeStatus} from '../src/file'
+
+describe('yaml filter parsing tests', () => {
+  test('throws if yaml is not a dictionary', () => {
+    const yaml = 'not a dictionary'
+    const t = () => new Filter(yaml)
+    expect(t).toThrow(/^Invalid filter.*/)
+  })
+  test('throws if pattern is not a string', () => {
+    const yaml = `
+    src:
+      - src/**/*.js
+      - dict:
+          some: value
+    `
+    const t = () => new Filter(yaml)
+    expect(t).toThrow(/^Invalid filter.*/)
+  })
+})
+
+describe('matching tests', () => {
+  test('matches single inline rule', () => {
+    const yaml = `
+    src: "src/**/*.js"
+    `
+    let filter = new Filter(yaml)
+    const files = modified(['src/app/module/file.js'])
+    const match = filter.match(files)
+    expect(match.src).toEqual(files)
+  })
+  test('matches single rule in single group', () => {
+    const yaml = `
+    src:
+      - src/**/*.js
+    `
+    const filter = new Filter(yaml)
+    const files = modified(['src/app/module/file.js'])
+    const match = filter.match(files)
+    expect(match.src).toEqual(files)
+  })
+
+  test('no match when file is in different folder', () => {
+    const yaml = `
+    src:
+      - src/**/*.js
+    `
+    const filter = new Filter(yaml)
+    const match = filter.match(modified(['not_src/other_file.js']))
+    expect(match.src).toEqual([])
+  })
+
+  test('match only within second groups ', () => {
+    const yaml = `
+    src:
+      - src/**/*.js
+    test:
+      - test/**/*.js
+    `
+    const filter = new Filter(yaml)
+    const files = modified(['test/test.js'])
+    const match = filter.match(files)
+    expect(match.src).toEqual([])
+    expect(match.test).toEqual(files)
+  })
+
+  test('match only withing second rule of single group', () => {
+    const yaml = `
+    src:
+      - src/**/*.js
+      - test/**/*.js
+    `
+    const filter = new Filter(yaml)
+    const files = modified(['test/test.js'])
+    const match = filter.match(files)
+    expect(match.src).toEqual(files)
+  })
+
+  test('matches anything', () => {
+    const yaml = `
+    any:
+      - "**"
+    `
+    const filter = new Filter(yaml)
+    const files = modified(['test/test.js'])
+    const match = filter.match(files)
+    expect(match.any).toEqual(files)
+  })
+
+  test('globbing matches path where file or folder name starts with dot', () => {
+    const yaml = `
+    dot:
+      - "**/*.js"
+    `
+    const filter = new Filter(yaml)
+    const files = modified(['.test/.test.js'])
+    const match = filter.match(files)
+    expect(match.dot).toEqual(files)
+  })
+
+  test('matches path based on rules included using YAML anchor', () => {
+    const yaml = `
+    shared: &shared
+      - common/**/*
+      - config/**/*
+    src:
+      - *shared
+      - src/**/*
+    `
+    const filter = new Filter(yaml)
+    const files = modified(['config/settings.yml'])
+    const match = filter.match(files)
+    expect(match.src).toEqual(files)
+  })
+})
+
+describe('matching specific change status', () => {
+  test('does not match modified file as added', () => {
+    const yaml = `
+    add:
+      - added: "**/*"
+    `
+    let filter = new Filter(yaml)
+    const match = filter.match(modified(['file.js']))
+    expect(match.add).toEqual([])
+  })
+
+  test('match added file as added', () => {
+    const yaml = `
+    add:
+      - added: "**/*"
+    `
+    let filter = new Filter(yaml)
+    const files = [{status: ChangeStatus.Added, filename: 'file.js'}]
+    const match = filter.match(files)
+    expect(match.add).toEqual(files)
+  })
+
+  test('matches when multiple statuses are configured', () => {
+    const yaml = `
+    addOrModify:
+      - added|modified: "**/*"
+    `
+    let filter = new Filter(yaml)
+    const files = [{status: ChangeStatus.Modified, filename: 'file.js'}]
+    const match = filter.match(files)
+    expect(match.addOrModify).toEqual(files)
+  })
+})
+
+function modified(paths: string[]): File[] {
+  return paths.map(filename => {
+    return {filename, status: ChangeStatus.Modified}
+  })
+}
--- a/tests/git.test.ts
+++ b/tests/git.test.ts
@@ -0,0 +1,29 @@
+import * as git from '../src/git'
+import {ChangeStatus} from '../src/file'
+
+describe('parsing output of the git diff command', () => {
+  test('parseGitDiffOutput returns files with correct change status', async () => {
+    const files = git.parseGitDiffOutput(
+      'A\u0000LICENSE\u0000' + 'M\u0000src/index.ts\u0000' + 'D\u0000src/main.ts\u0000'
+    )
+    expect(files.length).toBe(3)
+    expect(files[0].filename).toBe('LICENSE')
+    expect(files[0].status).toBe(ChangeStatus.Added)
+    expect(files[1].filename).toBe('src/index.ts')
+    expect(files[1].status).toBe(ChangeStatus.Modified)
+    expect(files[2].filename).toBe('src/main.ts')
+    expect(files[2].status).toBe(ChangeStatus.Deleted)
+  })
+})
+
+describe('git utility function tests (those not invoking git)', () => {
+  test('Trims "refs/" and "heads/" from ref', () => {
+    expect(git.getShortName('refs/heads/master')).toBe('master')
+    expect(git.getShortName('heads/master')).toBe('heads/master')
+    expect(git.getShortName('master')).toBe('master')
+
+    expect(git.getShortName('refs/tags/v1')).toBe('v1')
+    expect(git.getShortName('tags/v1')).toBe('tags/v1')
+    expect(git.getShortName('v1')).toBe('v1')
+  })
+})
--- a/tests/main.test.ts
+++ b/tests/main.test.ts
@@ -1,93 +0,0 @@
-import Filter from '../src/filter'
-
-describe('yaml filter parsing tests', () => {
-  test('throws if yaml is not a dictionary', () => {
-    const yaml = 'not a dictionary'
-    const t = () => new Filter(yaml)
-    expect(t).toThrow(/^Invalid filter.*/)
-  })
-  test('throws on invalid yaml', () => {
-    const yaml = `
-    src:
-      src/**/*.js
-    `
-    const t = () => new Filter(yaml)
-    expect(t).toThrow(/^Invalid filter.*/)
-  })
-  test('throws if pattern is not a string', () => {
-    const yaml = `
-    src:
-      - src/**/*.js
-      - dict:
-          some: value
-    `
-    const t = () => new Filter(yaml)
-    expect(t).toThrow(/^Invalid filter.*/)
-  })
-})
-
-describe('matching tests', () => {
-  test('matches single rule in single group', () => {
-    const yaml = `
-    src:
-      - src/**/*.js
-    `
-    const filter = new Filter(yaml)
-    const match = filter.match(['src/app/module/file.js'])
-    expect(match.src).toBeTruthy()
-  })
-
-  test('no match when file is in different folder', () => {
-    const yaml = `
-    src:
-      - src/**/*.js
-    `
-    const filter = new Filter(yaml)
-    const match = filter.match(['not_src/other_file.js'])
-    expect(match.src).toBeFalsy()
-  })
-
-  test('match only within second groups ', () => {
-    const yaml = `
-    src:
-      - src/**/*.js
-    test:
-      - test/**/*.js
-    `
-    const filter = new Filter(yaml)
-    const match = filter.match(['test/test.js'])
-    expect(match.src).toBeFalsy()
-    expect(match.test).toBeTruthy()
-  })
-
-  test('match only withing second rule of single group', () => {
-    const yaml = `
-    src:
-      - src/**/*.js
-      - test/**/*.js
-    `
-    const filter = new Filter(yaml)
-    const match = filter.match(['test/test.js'])
-    expect(match.src).toBeTruthy()
-  })
-
-  test('matches anything', () => {
-    const yaml = `
-    any:
-      - "**/*"
-    `
-    const filter = new Filter(yaml)
-    const match = filter.match(['test/test.js'])
-    expect(match.any).toBeTruthy()
-  })
-
-  test('globbing matches path where file or folder name starts with dot', () => {
-    const yaml = `
-    dot:
-      - "**/*.js"
-    `
-    const filter = new Filter(yaml)
-    const match = filter.match(['.test/.test.js'])
-    expect(match.dot).toBeTruthy()
-  })
-})
--- a/tests/shell-escape.test.ts
+++ b/tests/shell-escape.test.ts
@@ -0,0 +1,16 @@
+import shellEscape from '../src/shell-escape'
+
+test('simple path escaped', () => {
+  expect(shellEscape('file')).toBe("'file'")
+})
+
+test('path with space is wrapped with single quotes', () => {
+  expect(shellEscape('file with space')).toBe("'file with space'")
+})
+
+test('path with quote is divided into quoted segments and escaped quote', () => {
+  expect(shellEscape("file'with quote")).toBe("'file'\\''with quote'")
+})
+test('path with leading quote does not have double quotes at beginning', () => {
+  expect(shellEscape("'file-leading-quote")).toBe("\\''file-leading-quote'")
+})
--- a/action.yml
+++ b/action.yml
@@ -1,17 +1,42 @@
-name: 'Pull request changed files filter'
-description: 'Enables conditional execution of workflow job steps considering which files are modified by a pull request.'
+name: 'Paths filter'
+description: 'Execute your workflow steps only if relevant files are modified.'
 author: 'Michal Dorner <dorner.michal@gmail.com>'
 inputs:
  token:
    description: 'GitHub Access Token'
    required: false
    default: ${{ github.token }}
+  working-directory:
+    description: 'Relative path under $GITHUB_WORKSPACE where the repository was checked out.'
+    required: false
+  base:
+    description: |
+      Git reference (e.g. branch name) against which the changes will be detected. Defaults to repository default branch (e.g. master).
+      If it references same branch it was pushed to, changes are detected against the most recent commit before the push.
+      This option is ignored if action is triggered by pull_request event.
+    required: false
  filters:
    description: 'Path to the configuration file or YAML string with filters definition'
    required: true
+  list-files:
+    description: |
+      Enables listing of files matching the filter:
+        'none'  - Disables listing of matching files (default).
+        'json'  - Matching files paths are serialized as JSON array.
+        'shell' - Matching files paths are escaped and space-delimited. Output is usable as command line argument list in linux shell.
+    required: true
+    default: none
+  initial-fetch-depth:
+    description: |
+      How many commits are initially fetched from base branch.
+      If needed, each subsequent fetch doubles the previously requested number of commits
+      until the merge-base is found or there are no more commits in the history.
+      This option takes effect only when changes are detected using git against different base branch.
+    required: false
+    default: '10'
 runs:
  using: 'node12'
  main: 'dist/index.js'
 branding:
  color: blue
-  icon: filter
+  icon: filter
--- a/dist/index.js
+++ b/dist/index.js
@@ -3788,45 +3788,206 @@ module.exports = require("child_process");

 "use strict";

-var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, generator) {
-    function adopt(value) { return value instanceof P ? value : new P(function (resolve) { resolve(value); }); }
-    return new (P || (P = Promise))(function (resolve, reject) {
-        function fulfilled(value) { try { step(generator.next(value)); } catch (e) { reject(e); } }
-        function rejected(value) { try { step(generator["throw"](value)); } catch (e) { reject(e); } }
-        function step(result) { result.done ? resolve(result.value) : adopt(result.value).then(fulfilled, rejected); }
-        step((generator = generator.apply(thisArg, _arguments || [])).next());
-    });
+var __createBinding = (this && this.__createBinding) || (Object.create ? (function(o, m, k, k2) {
+    if (k2 === undefined) k2 = k;
+    Object.defineProperty(o, k2, { enumerable: true, get: function() { return m[k]; } });
+}) : (function(o, m, k, k2) {
+    if (k2 === undefined) k2 = k;
+    o[k2] = m[k];
+}));
+var __setModuleDefault = (this && this.__setModuleDefault) || (Object.create ? (function(o, v) {
+    Object.defineProperty(o, "default", { enumerable: true, value: v });
+}) : function(o, v) {
+    o["default"] = v;
+});
+var __importStar = (this && this.__importStar) || function (mod) {
+    if (mod && mod.__esModule) return mod;
+    var result = {};
+    if (mod != null) for (var k in mod) if (Object.hasOwnProperty.call(mod, k)) __createBinding(result, mod, k);
+    __setModuleDefault(result, mod);
+    return result;
+};
+var __importDefault = (this && this.__importDefault) || function (mod) {
+    return (mod && mod.__esModule) ? mod : { "default": mod };
 };
 Object.defineProperty(exports, "__esModule", { value: true });
-exports.getChangedFiles = exports.fetchBranch = void 0;
-const exec_1 = __webpack_require__(986);
-function fetchBranch(base) {
-    return __awaiter(this, void 0, void 0, function* () {
-        const exitCode = yield exec_1.exec('git', ['fetch', '--depth=1', 'origin', base]);
-        if (exitCode !== 0) {
-            throw new Error(`Fetching branch ${base} failed, exiting`);
-        }
-    });
+exports.getShortName = exports.getCurrentRef = exports.listAllFilesAsAdded = exports.parseGitDiffOutput = exports.getChangesSinceMergeBase = exports.getChanges = exports.getChangesInLastCommit = exports.NULL_SHA = void 0;
+const exec_1 = __importDefault(__webpack_require__(807));
+const core = __importStar(__webpack_require__(470));
+const file_1 = __webpack_require__(258);
+exports.NULL_SHA = '0000000000000000000000000000000000000000';
+async function getChangesInLastCommit() {
+    core.startGroup(`Change detection in last commit`);
+    let output = '';
+    try {
+        output = (await exec_1.default('git', ['log', '--format=', '--no-renames', '--name-status', '-z', '-n', '1'])).stdout;
+    }
+    finally {
+        fixStdOutNullTermination();
+        core.endGroup();
+    }
+    return parseGitDiffOutput(output);
 }
-exports.fetchBranch = fetchBranch;
-function getChangedFiles(base) {
-    return __awaiter(this, void 0, void 0, function* () {
-        let output = '';
-        const exitCode = yield exec_1.exec('git', ['diff-index', '--name-only', base], {
-            listeners: {
-                stdout: (data) => (output += data.toString())
+exports.getChangesInLastCommit = getChangesInLastCommit;
+async function getChanges(ref) {
+    if (!(await hasCommit(ref))) {
+        // Fetch single commit
+        core.startGroup(`Fetching ${ref} from origin`);
+        await exec_1.default('git', ['fetch', '--depth=1', '--no-tags', '--no-auto-gc', 'origin', ref]);
+        core.endGroup();
+    }
+    // Get differences between ref and HEAD
+    core.startGroup(`Change detection ${ref}..HEAD`);
+    let output = '';
+    try {
+        // Two dots '..' change detection - directly compares two versions
+        output = (await exec_1.default('git', ['diff', '--no-renames', '--name-status', '-z', `${ref}..HEAD`])).stdout;
+    }
+    finally {
+        fixStdOutNullTermination();
+        core.endGroup();
+    }
+    return parseGitDiffOutput(output);
+}
+exports.getChanges = getChanges;
+async function getChangesSinceMergeBase(ref, initialFetchDepth) {
+    if (!(await hasCommit(ref))) {
+        // Fetch and add base branch
+        core.startGroup(`Fetching ${ref}`);
+        try {
+            await exec_1.default('git', ['fetch', `--depth=${initialFetchDepth}`, '--no-tags', 'origin', `${ref}:${ref}`]);
+        }
+        finally {
+            core.endGroup();
+        }
+    }
+    async function hasMergeBase() {
+        return (await exec_1.default('git', ['merge-base', ref, 'HEAD'], { ignoreReturnCode: true })).code === 0;
+    }
+    async function countCommits() {
+        return (await getNumberOfCommits('HEAD')) + (await getNumberOfCommits(ref));
+    }
+    core.startGroup(`Searching for merge-base with ${ref}`);
+    // Fetch more commits until merge-base is found
+    if (!(await hasMergeBase())) {
+        let deepen = initialFetchDepth;
+        let lastCommitsCount = await countCommits();
+        do {
+            await exec_1.default('git', ['fetch', `--deepen=${deepen}`, '--no-tags', '--no-auto-gc']);
+            const count = await countCommits();
+            if (count <= lastCommitsCount) {
+                core.info('No merge base found - all files will be listed as added');
+                core.endGroup();
+                return await listAllFilesAsAdded();
            }
-        });
-        if (exitCode !== 0) {
-            throw new Error(`Couldn't determine changed files, exiting`);
-        }
-        return output
-            .split('\n')
-            .map(s => s.trim())
-            .filter(s => s.length > 0);
-    });
+            lastCommitsCount = count;
+            deepen = Math.min(deepen * 2, Number.MAX_SAFE_INTEGER);
+        } while (!(await hasMergeBase()));
+    }
+    core.endGroup();
+    // Get changes introduced on HEAD compared to ref
+    core.startGroup(`Change detection ${ref}...HEAD`);
+    let output = '';
+    try {
+        // Three dots '...' change detection - finds merge-base and compares against it
+        output = (await exec_1.default('git', ['diff', '--no-renames', '--name-status', '-z', `${ref}...HEAD`])).stdout;
+    }
+    finally {
+        fixStdOutNullTermination();
+        core.endGroup();
+    }
+    return parseGitDiffOutput(output);
 }
-exports.getChangedFiles = getChangedFiles;
+exports.getChangesSinceMergeBase = getChangesSinceMergeBase;
+function parseGitDiffOutput(output) {
+    const tokens = output.split('\u0000').filter(s => s.length > 0);
+    const files = [];
+    for (let i = 0; i + 1 < tokens.length; i += 2) {
+        files.push({
+            status: statusMap[tokens[i]],
+            filename: tokens[i + 1]
+        });
+    }
+    return files;
+}
+exports.parseGitDiffOutput = parseGitDiffOutput;
+async function listAllFilesAsAdded() {
+    core.startGroup('Listing all files tracked by git');
+    let output = '';
+    try {
+        output = (await exec_1.default('git', ['ls-files', '-z'])).stdout;
+    }
+    finally {
+        fixStdOutNullTermination();
+        core.endGroup();
+    }
+    return output
+        .split('\u0000')
+        .filter(s => s.length > 0)
+        .map(path => ({
+        status: file_1.ChangeStatus.Added,
+        filename: path
+    }));
+}
+exports.listAllFilesAsAdded = listAllFilesAsAdded;
+async function getCurrentRef() {
+    core.startGroup(`Determining current ref`);
+    try {
+        const branch = (await exec_1.default('git', ['branch', '--show-current'])).stdout.trim();
+        if (branch) {
+            return branch;
+        }
+        const describe = await exec_1.default('git', ['describe', '--tags', '--exact-match'], { ignoreReturnCode: true });
+        if (describe.code === 0) {
+            return describe.stdout.trim();
+        }
+        return (await exec_1.default('git', ['rev-parse', 'HEAD'])).stdout.trim();
+    }
+    finally {
+        core.endGroup();
+    }
+}
+exports.getCurrentRef = getCurrentRef;
+function getShortName(ref) {
+    if (!ref)
+        return '';
+    const heads = 'refs/heads/';
+    const tags = 'refs/tags/';
+    if (ref.startsWith(heads))
+        return ref.slice(heads.length);
+    if (ref.startsWith(tags))
+        return ref.slice(tags.length);
+    return ref;
+}
+exports.getShortName = getShortName;
+async function hasCommit(ref) {
+    core.startGroup(`Checking if commit for ${ref} is locally available`);
+    try {
+        return (await exec_1.default('git', ['cat-file', '-e', `${ref}^{commit}`], { ignoreReturnCode: true })).code === 0;
+    }
+    finally {
+        core.endGroup();
+    }
+}
+async function getNumberOfCommits(ref) {
+    const output = (await exec_1.default('git', ['rev-list', `--count`, ref])).stdout;
+    const count = parseInt(output);
+    return isNaN(count) ? 0 : count;
+}
+function fixStdOutNullTermination() {
+    // Previous command uses NULL as delimiters and output is printed to stdout.
+    // We have to make sure next thing written to stdout will start on new line.
+    // Otherwise things like ::set-output wouldn't work.
+    core.info('');
+}
+const statusMap = {
+    A: file_1.ChangeStatus.Added,
+    C: file_1.ChangeStatus.Copied,
+    D: file_1.ChangeStatus.Deleted,
+    M: file_1.ChangeStatus.Modified,
+    R: file_1.ChangeStatus.Renamed,
+    U: file_1.ChangeStatus.Unmerged
+};


 /***/ }),
@@ -4461,15 +4622,6 @@ var __importStar = (this && this.__importStar) || function (mod) {
    __setModuleDefault(result, mod);
    return result;
 };
-var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, generator) {
-    function adopt(value) { return value instanceof P ? value : new P(function (resolve) { resolve(value); }); }
-    return new (P || (P = Promise))(function (resolve, reject) {
-        function fulfilled(value) { try { step(generator.next(value)); } catch (e) { reject(e); } }
-        function rejected(value) { try { step(generator["throw"](value)); } catch (e) { reject(e); } }
-        function step(result) { result.done ? resolve(result.value) : adopt(result.value).then(fulfilled, rejected); }
-        step((generator = generator.apply(thisArg, _arguments || [])).next());
-    });
-};
 var __importDefault = (this && this.__importDefault) || function (mod) {
    return (mod && mod.__esModule) ? mod : { "default": mod };
 };
@@ -4477,30 +4629,34 @@ Object.defineProperty(exports, "__esModule", { value: true });
 const fs = __importStar(__webpack_require__(747));
 const core = __importStar(__webpack_require__(470));
 const github = __importStar(__webpack_require__(469));
-const filter_1 = __importDefault(__webpack_require__(235));
+const filter_1 = __webpack_require__(235);
+const file_1 = __webpack_require__(258);
 const git = __importStar(__webpack_require__(136));
-function run() {
-    return __awaiter(this, void 0, void 0, function* () {
-        try {
-            const token = core.getInput('token', { required: false });
-            const filtersInput = core.getInput('filters', { required: true });
-            const filtersYaml = isPathInput(filtersInput) ? getConfigFileContent(filtersInput) : filtersInput;
-            if (github.context.eventName !== 'pull_request') {
-                core.setFailed('This action can be triggered only by pull_request event');
-                return;
-            }
-            const pr = github.context.payload.pull_request;
-            const filter = new filter_1.default(filtersYaml);
-            const files = token ? yield getChangedFilesFromApi(token, pr) : yield getChangedFilesFromGit(pr);
-            const result = filter.match(files);
-            for (const key in result) {
-                core.setOutput(key, String(result[key]));
-            }
+const shell_escape_1 = __importDefault(__webpack_require__(751));
+async function run() {
+    try {
+        const workingDirectory = core.getInput('working-directory', { required: false });
+        if (workingDirectory) {
+            process.chdir(workingDirectory);
        }
-        catch (error) {
-            core.setFailed(error.message);
+        const token = core.getInput('token', { required: false });
+        const base = core.getInput('base', { required: false });
+        const filtersInput = core.getInput('filters', { required: true });
+        const filtersYaml = isPathInput(filtersInput) ? getConfigFileContent(filtersInput) : filtersInput;
+        const listFiles = core.getInput('list-files', { required: false }).toLowerCase() || 'none';
+        const initialFetchDepth = parseInt(core.getInput('initial-fetch-depth', { required: false })) || 10;
+        if (!isExportFormat(listFiles)) {
+            core.setFailed(`Input parameter 'list-files' is set to invalid value '${listFiles}'`);
+            return;
        }
-    });
+        const filter = new filter_1.Filter(filtersYaml);
+        const files = await getChangedFiles(token, base, initialFetchDepth);
+        const results = filter.match(files);
+        exportResults(results, listFiles);
+    }
+    catch (error) {
+        core.setFailed(error.message);
+    }
 }
 function isPathInput(text) {
    return !text.includes('\n');
@@ -4514,36 +4670,133 @@ function getConfigFileContent(configPath) {
    }
    return fs.readFileSync(configPath, { encoding: 'utf8' });
 }
-// Fetch base branch and use `git diff` to determine changed files
-function getChangedFilesFromGit(pullRequest) {
-    return __awaiter(this, void 0, void 0, function* () {
-        core.debug('Fetching base branch and using `git diff-index` to determine changed files');
-        const baseRef = pullRequest.base.ref;
-        yield git.fetchBranch(baseRef);
-        return yield git.getChangedFiles(pullRequest.base.sha);
-    });
+async function getChangedFiles(token, base, initialFetchDepth) {
+    if (github.context.eventName === 'pull_request' || github.context.eventName === 'pull_request_target') {
+        const pr = github.context.payload.pull_request;
+        if (token) {
+            return await getChangedFilesFromApi(token, pr);
+        }
+        core.info('Github token is not available - changes will be detected from PRs merge commit');
+        return await git.getChangesInLastCommit();
+    }
+    else if (github.context.eventName === 'push') {
+        return getChangedFilesFromPush(base, initialFetchDepth);
+    }
+    else {
+        throw new Error('This action can be triggered only by pull_request, pull_request_target or push event');
+    }
 }
-// Uses github REST api to get list of files changed in PR
-function getChangedFilesFromApi(token, pullRequest) {
-    return __awaiter(this, void 0, void 0, function* () {
-        core.debug('Fetching list of modified files from Github API');
-        const client = new github.GitHub(token);
-        const pageSize = 100;
-        const files = [];
-        for (let page = 0; page * pageSize < pullRequest.changed_files; page++) {
-            const response = yield client.pulls.listFiles({
-                owner: github.context.repo.owner,
-                repo: github.context.repo.repo,
-                pull_number: pullRequest.number,
-                page,
-                per_page: pageSize
-            });
-            for (const row of response.data) {
-                files.push(row.filename);
+async function getChangedFilesFromPush(base, initialFetchDepth) {
+    var _a;
+    const push = github.context.payload;
+    const defaultRef = (_a = push.repository) === null || _a === void 0 ? void 0 : _a.default_branch;
+    const pushRef = git.getShortName(push.ref) ||
+        (core.warning(`'ref' field is missing in PUSH event payload - using current branch, tag or commit SHA`),
+            await git.getCurrentRef());
+    const baseRef = git.getShortName(base) || defaultRef;
+    if (!baseRef) {
+        throw new Error("This action requires 'base' input to be configured or 'repository.default_branch' to be set in the event payload");
+    }
+    // If base references same branch it was pushed to,
+    // we will do comparison against the previously pushed commit
+    if (baseRef === pushRef) {
+        if (!push.before) {
+            core.warning(`'before' field is missing in PUSH event payload - changes will be detected from last commit`);
+            return await git.getChangesInLastCommit();
+        }
+        // If there is no previously pushed commit,
+        // we will do comparison against the default branch or return all as added
+        if (push.before === git.NULL_SHA) {
+            if (defaultRef && baseRef !== defaultRef) {
+                core.info(`First push of a branch detected - changes will be detected against the default branch ${defaultRef}`);
+                return await git.getChangesSinceMergeBase(defaultRef, initialFetchDepth);
+            }
+            else {
+                core.info('Initial push detected - all files will be listed as added');
+                return await git.listAllFilesAsAdded();
            }
        }
-        return files;
-    });
+        core.info(`Changes will be detected against the last previously pushed commit on same branch (${pushRef})`);
+        return await git.getChanges(push.before);
+    }
+    // Changes introduced by current branch against the base branch
+    core.info(`Changes will be detected against the branch ${baseRef}`);
+    return await git.getChangesSinceMergeBase(baseRef, initialFetchDepth);
+}
+// Uses github REST api to get list of files changed in PR
+async function getChangedFilesFromApi(token, pullRequest) {
+    core.info(`Fetching list of changed files for PR#${pullRequest.number} from Github API`);
+    const client = new github.GitHub(token);
+    const pageSize = 100;
+    const files = [];
+    for (let page = 0; page * pageSize < pullRequest.changed_files; page++) {
+        const response = await client.pulls.listFiles({
+            owner: github.context.repo.owner,
+            repo: github.context.repo.repo,
+            pull_number: pullRequest.number,
+            page,
+            per_page: pageSize
+        });
+        for (const row of response.data) {
+            // There's no obvious use-case for detection of renames
+            // Therefore we treat it as if rename detection in git diff was turned off.
+            // Rename is replaced by delete of original filename and add of new filename
+            if (row.status === file_1.ChangeStatus.Renamed) {
+                files.push({
+                    filename: row.filename,
+                    status: file_1.ChangeStatus.Added
+                });
+                files.push({
+                    // 'previous_filename' for some unknown reason isn't in the type definition or documentation
+                    filename: row.previous_filename,
+                    status: file_1.ChangeStatus.Deleted
+                });
+            }
+            else {
+                files.push({
+                    filename: row.filename,
+                    status: row.status
+                });
+            }
+        }
+    }
+    return files;
+}
+function exportResults(results, format) {
+    core.info('Results:');
+    for (const [key, files] of Object.entries(results)) {
+        const value = files.length > 0;
+        core.startGroup(`Filter ${key} = ${value}`);
+        if (files.length > 0) {
+            core.info('Matching files:');
+            for (const file of files) {
+                core.info(`${file.filename} [${file.status}]`);
+            }
+        }
+        else {
+            core.info('Matching files: none');
+        }
+        core.setOutput(key, value);
+        if (format !== 'none') {
+            const filesValue = serializeExport(files, format);
+            core.setOutput(`${key}_files`, filesValue);
+        }
+    }
+    core.endGroup();
+}
+function serializeExport(files, format) {
+    const fileNames = files.map(file => file.filename);
+    switch (format) {
+        case 'json':
+            return JSON.stringify(fileNames);
+        case 'shell':
+            return fileNames.map(shell_escape_1.default).join(' ');
+        default:
+            return '';
+    }
+}
+function isExportFormat(value) {
+    return value === 'none' || value === 'shell' || value === 'json';
 }
 run();

@@ -4632,43 +4885,98 @@ var __importStar = (this && this.__importStar) || function (mod) {
    return result;
 };
 Object.defineProperty(exports, "__esModule", { value: true });
+exports.Filter = void 0;
 const jsyaml = __importStar(__webpack_require__(414));
 const minimatch = __importStar(__webpack_require__(595));
+// Minimatch options used in all matchers
+const MinimatchOptions = {
+    dot: true
+};
 class Filter {
+    // Creates instance of Filter and load rules from YAML if it's provided
    constructor(yaml) {
        this.rules = {};
-        const doc = jsyaml.safeLoad(yaml);
-        if (typeof doc !== 'object') {
-            this.throwInvalidFormatError();
-        }
-        const opts = {
-            dot: true
-        };
-        for (const name of Object.keys(doc)) {
-            const patterns = doc[name];
-            if (!Array.isArray(patterns)) {
-                this.throwInvalidFormatError();
-            }
-            if (!patterns.every(x => typeof x === 'string')) {
-                this.throwInvalidFormatError();
-            }
-            this.rules[name] = patterns.map(x => new minimatch.Minimatch(x, opts));
+        if (yaml) {
+            this.load(yaml);
        }
    }
-    // Returns dictionary with match result per rules group
-    match(paths) {
+    // Load rules from YAML string
+    load(yaml) {
+        if (!yaml) {
+            return;
+        }
+        const doc = jsyaml.safeLoad(yaml);
+        if (typeof doc !== 'object') {
+            this.throwInvalidFormatError('Root element is not an object');
+        }
+        for (const [key, item] of Object.entries(doc)) {
+            this.rules[key] = this.parseFilterItemYaml(item);
+        }
+    }
+    match(files) {
        const result = {};
        for (const [key, patterns] of Object.entries(this.rules)) {
-            const match = paths.some(fileName => patterns.some(rule => rule.match(fileName)));
-            result[key] = match;
+            result[key] = files.filter(file => this.isMatch(file, patterns));
        }
        return result;
    }
-    throwInvalidFormatError() {
-        throw new Error('Invalid filter YAML format: Expected dictionary of string arrays');
+    isMatch(file, patterns) {
+        return patterns.some(rule => (rule.status === undefined || rule.status.includes(file.status)) && rule.matcher.match(file.filename));
+    }
+    parseFilterItemYaml(item) {
+        if (Array.isArray(item)) {
+            return flat(item.map(i => this.parseFilterItemYaml(i)));
+        }
+        if (typeof item === 'string') {
+            return [{ status: undefined, matcher: new minimatch.Minimatch(item, MinimatchOptions) }];
+        }
+        if (typeof item === 'object') {
+            return Object.entries(item).map(([key, pattern]) => {
+                if (typeof key !== 'string' || typeof pattern !== 'string') {
+                    this.throwInvalidFormatError(`Expected [key:string]= pattern:string, but [${key}:${typeof key}]= ${pattern}:${typeof pattern} found`);
+                }
+                return {
+                    status: key
+                        .split('|')
+                        .map(x => x.trim())
+                        .filter(x => x.length > 0)
+                        .map(x => x.toLowerCase()),
+                    matcher: new minimatch.Minimatch(pattern, MinimatchOptions)
+                };
+            });
+        }
+        this.throwInvalidFormatError(`Unexpected element type '${typeof item}'`);
+    }
+    throwInvalidFormatError(message) {
+        throw new Error(`Invalid filter YAML format: ${message}.`);
    }
 }
-exports.default = Filter;
+exports.Filter = Filter;
+// Creates a new array with all sub-array elements concatenated
+// In future could be replaced by Array.prototype.flat (supported on Node.js 11+)
+function flat(arr) {
+    return arr.reduce((acc, val) => acc.concat(val), []);
+}
+
+
+/***/ }),
+
+/***/ 258:
+/***/ (function(__unusedmodule, exports) {
+
+"use strict";
+
+Object.defineProperty(exports, "__esModule", { value: true });
+exports.ChangeStatus = void 0;
+var ChangeStatus;
+(function (ChangeStatus) {
+    ChangeStatus["Added"] = "added";
+    ChangeStatus["Copied"] = "copied";
+    ChangeStatus["Deleted"] = "deleted";
+    ChangeStatus["Modified"] = "modified";
+    ChangeStatus["Renamed"] = "renamed";
+    ChangeStatus["Unmerged"] = "unmerged";
+})(ChangeStatus = exports.ChangeStatus || (exports.ChangeStatus = {}));


 /***/ }),
@@ -15082,6 +15390,23 @@ function sync (path, options) {

 module.exports = require("fs");

+/***/ }),
+
+/***/ 751:
+/***/ (function(__unusedmodule, exports) {
+
+"use strict";
+
+// Credits to https://github.com/xxorax/node-shell-escape
+Object.defineProperty(exports, "__esModule", { value: true });
+function shellEscape(value) {
+    return `'${value.replace(/'/g, "'\\''")}'`
+        .replace(/^(?:'')+/g, '') // unduplicate single-quote at the beginning
+        .replace(/\\'''/g, "\\'"); // remove non-escaped single-quote if there are enclosed between 2 escaped
+}
+exports.default = shellEscape;
+
+
 /***/ }),

 /***/ 753:
@@ -15336,6 +15661,31 @@ exports.getUserAgent = getUserAgent;
 //# sourceMappingURL=index.js.map


+/***/ }),
+
+/***/ 807:
+/***/ (function(__unusedmodule, exports, __webpack_require__) {
+
+"use strict";
+
+Object.defineProperty(exports, "__esModule", { value: true });
+const exec_1 = __webpack_require__(986);
+// Wraps original exec() function
+// Returns exit code and whole stdout/stderr
+async function exec(commandLine, args, options) {
+    options = options || {};
+    let stdout = '';
+    let stderr = '';
+    options.listeners = {
+        stdout: (data) => (stdout += data.toString()),
+        stderr: (data) => (stderr += data.toString())
+    };
+    const code = await exec_1.exec(commandLine, args, options);
+    return { code, stdout, stderr };
+}
+exports.default = exec;
+
+
 /***/ }),

 /***/ 809:
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,5 +1,5 @@
 {
-  "name": "pr-changed-files-filter",
+  "name": "paths-filter",
  "version": "1.0.0",
  "lockfileVersion": 1,
  "requires": true,
@@ -3897,33 +3897,33 @@
      }
    },
    "@typescript-eslint/experimental-utils": {
-      "version": "3.0.0",
-      "resolved": "https://registry.npmjs.org/@typescript-eslint/experimental-utils/-/experimental-utils-3.0.0.tgz",
-      "integrity": "sha512-BN0vmr9N79M9s2ctITtChRuP1+Dls0x/wlg0RXW1yQ7WJKPurg6X3Xirv61J2sjPif4F8SLsFMs5Nzte0WYoTQ==",
+      "version": "3.3.0",
+      "resolved": "https://registry.npmjs.org/@typescript-eslint/experimental-utils/-/experimental-utils-3.3.0.tgz",
+      "integrity": "sha512-d4pGIAbu/tYsrPrdHCQ5xfadJGvlkUxbeBB56nO/VGmEDi/sKmfa5fGty5t5veL1OyJBrUmSiRn1R1qfVDydrg==",
      "dev": true,
      "requires": {
        "@types/json-schema": "^7.0.3",
-        "@typescript-eslint/typescript-estree": "3.0.0",
+        "@typescript-eslint/typescript-estree": "3.3.0",
        "eslint-scope": "^5.0.0",
        "eslint-utils": "^2.0.0"
      }
    },
    "@typescript-eslint/parser": {
-      "version": "3.0.0",
-      "resolved": "https://registry.npmjs.org/@typescript-eslint/parser/-/parser-3.0.0.tgz",
-      "integrity": "sha512-8RRCA9KLxoFNO0mQlrLZA0reGPd/MsobxZS/yPFj+0/XgMdS8+mO8mF3BDj2ZYQj03rkayhSJtF1HAohQ3iylw==",
+      "version": "3.3.0",
+      "resolved": "https://registry.npmjs.org/@typescript-eslint/parser/-/parser-3.3.0.tgz",
+      "integrity": "sha512-a7S0Sqn/+RpOOWTcaLw6RD4obsharzxmgMfdK24l364VxuBODXjuJM7ImCkSXEN7oz52aiZbXSbc76+2EsE91w==",
      "dev": true,
      "requires": {
        "@types/eslint-visitor-keys": "^1.0.0",
-        "@typescript-eslint/experimental-utils": "3.0.0",
-        "@typescript-eslint/typescript-estree": "3.0.0",
+        "@typescript-eslint/experimental-utils": "3.3.0",
+        "@typescript-eslint/typescript-estree": "3.3.0",
        "eslint-visitor-keys": "^1.1.0"
      }
    },
    "@typescript-eslint/typescript-estree": {
-      "version": "3.0.0",
-      "resolved": "https://registry.npmjs.org/@typescript-eslint/typescript-estree/-/typescript-estree-3.0.0.tgz",
-      "integrity": "sha512-nevQvHyNghsfLrrByzVIH4ZG3NROgJ8LZlfh3ddwPPH4CH7W4GAiSx5qu+xHuX5pWsq6q/eqMc1io840ZhAnUg==",
+      "version": "3.3.0",
+      "resolved": "https://registry.npmjs.org/@typescript-eslint/typescript-estree/-/typescript-estree-3.3.0.tgz",
+      "integrity": "sha512-3SqxylENltEvJsjjMSDCUx/edZNSC7wAqifUU1Ywp//0OWEZwMZJfecJud9XxJ/40rAKEbJMKBOQzeOjrLJFzQ==",
      "dev": true,
      "requires": {
        "debug": "^4.1.1",
@@ -3956,9 +3956,9 @@
      "dev": true
    },
    "acorn": {
-      "version": "6.4.1",
-      "resolved": "https://registry.npmjs.org/acorn/-/acorn-6.4.1.tgz",
-      "integrity": "sha512-ZVA9k326Nwrj3Cj9jlh3wGFutC2ZornPNARZwsNYqQYgN0EsV2d53w5RN/co65Ohn4sUAUtb1rSUAOD6XN9idA==",
+      "version": "7.3.1",
+      "resolved": "https://registry.npmjs.org/acorn/-/acorn-7.3.1.tgz",
+      "integrity": "sha512-tLc0wSnatxAQHVHUapaHdz72pi9KUyHjq5KyHjGg9Y8Ifdc79pTh2XvI6I1/chZbnM7QtNKzh66ooDogPZSleA==",
      "dev": true
    },
    "acorn-globals": {
@@ -4003,6 +4003,12 @@
        "uri-js": "^4.2.2"
      }
    },
+    "ansi-colors": {
+      "version": "3.2.4",
+      "resolved": "https://registry.npmjs.org/ansi-colors/-/ansi-colors-3.2.4.tgz",
+      "integrity": "sha512-hHUXGagefjN2iRrID63xckIvotOXOojhQKWIPUZ4mNUZ9nLZW+7FMNoE1lOkEhNWYsx/7ysGIuJYCiMAA9FnrA==",
+      "dev": true
+    },
    "ansi-escapes": {
      "version": "3.2.0",
      "resolved": "https://registry.npmjs.org/ansi-escapes/-/ansi-escapes-3.2.0.tgz",
@@ -5419,6 +5425,15 @@
        "once": "^1.4.0"
      }
    },
+    "enquirer": {
+      "version": "2.3.5",
+      "resolved": "https://registry.npmjs.org/enquirer/-/enquirer-2.3.5.tgz",
+      "integrity": "sha512-BNT1C08P9XD0vNg3J475yIUG+mVdp9T6towYFHUv897X0KoHBjB1shyrNmhmtHWKP17iSWgo7Gqh7BBuzLZMSA==",
+      "dev": true,
+      "requires": {
+        "ansi-colors": "^3.2.1"
+      }
+    },
    "error-ex": {
      "version": "1.3.2",
      "resolved": "https://registry.npmjs.org/error-ex/-/error-ex-1.3.2.tgz",
@@ -5487,79 +5502,214 @@
      }
    },
    "eslint": {
-      "version": "5.16.0",
-      "resolved": "https://registry.npmjs.org/eslint/-/eslint-5.16.0.tgz",
-      "integrity": "sha512-S3Rz11i7c8AA5JPv7xAH+dOyq/Cu/VXHiHXBPOU1k/JAM5dXqQPt3qcrhpHSorXmrpu2g0gkIBVXAqCpzfoZIg==",
+      "version": "7.3.0",
+      "resolved": "https://registry.npmjs.org/eslint/-/eslint-7.3.0.tgz",
+      "integrity": "sha512-dJMVXwfU5PT1cj2Nv2VPPrKahKTGdX+5Dh0Q3YuKt+Y2UhdL2YbzsVaBMyG9HC0tBismlv/r1+eZqs6SMIV38Q==",
      "dev": true,
      "requires": {
        "@babel/code-frame": "^7.0.0",
-        "ajv": "^6.9.1",
-        "chalk": "^2.1.0",
-        "cross-spawn": "^6.0.5",
+        "ajv": "^6.10.0",
+        "chalk": "^4.0.0",
+        "cross-spawn": "^7.0.2",
        "debug": "^4.0.1",
        "doctrine": "^3.0.0",
-        "eslint-scope": "^4.0.3",
-        "eslint-utils": "^1.3.1",
-        "eslint-visitor-keys": "^1.0.0",
-        "espree": "^5.0.1",
-        "esquery": "^1.0.1",
+        "enquirer": "^2.3.5",
+        "eslint-scope": "^5.1.0",
+        "eslint-utils": "^2.0.0",
+        "eslint-visitor-keys": "^1.2.0",
+        "espree": "^7.1.0",
+        "esquery": "^1.2.0",
        "esutils": "^2.0.2",
        "file-entry-cache": "^5.0.1",
        "functional-red-black-tree": "^1.0.1",
-        "glob": "^7.1.2",
-        "globals": "^11.7.0",
+        "glob-parent": "^5.0.0",
+        "globals": "^12.1.0",
        "ignore": "^4.0.6",
        "import-fresh": "^3.0.0",
        "imurmurhash": "^0.1.4",
-        "inquirer": "^6.2.2",
-        "js-yaml": "^3.13.0",
+        "is-glob": "^4.0.0",
+        "js-yaml": "^3.13.1",
        "json-stable-stringify-without-jsonify": "^1.0.1",
-        "levn": "^0.3.0",
-        "lodash": "^4.17.11",
+        "levn": "^0.4.1",
+        "lodash": "^4.17.14",
        "minimatch": "^3.0.4",
-        "mkdirp": "^0.5.1",
        "natural-compare": "^1.4.0",
-        "optionator": "^0.8.2",
-        "path-is-inside": "^1.0.2",
+        "optionator": "^0.9.1",
        "progress": "^2.0.0",
-        "regexpp": "^2.0.1",
-        "semver": "^5.5.1",
-        "strip-ansi": "^4.0.0",
-        "strip-json-comments": "^2.0.1",
+        "regexpp": "^3.1.0",
+        "semver": "^7.2.1",
+        "strip-ansi": "^6.0.0",
+        "strip-json-comments": "^3.1.0",
        "table": "^5.2.3",
-        "text-table": "^0.2.0"
+        "text-table": "^0.2.0",
+        "v8-compile-cache": "^2.0.3"
      },
      "dependencies": {
-        "eslint-scope": {
-          "version": "4.0.3",
-          "resolved": "https://registry.npmjs.org/eslint-scope/-/eslint-scope-4.0.3.tgz",
-          "integrity": "sha512-p7VutNr1O/QrxysMo3E45FjYDTeXBy0iTltPFNSqKAIfjDSXC+4dj+qfyuD8bfAXrW/y6lW3O76VaYNPKfpKrg==",
+        "ansi-styles": {
+          "version": "4.2.1",
+          "resolved": "https://registry.npmjs.org/ansi-styles/-/ansi-styles-4.2.1.tgz",
+          "integrity": "sha512-9VGjrMsG1vePxcSweQsN20KY/c4zN0h9fLjqAbwbPfahM3t+NL+M9HC8xeXG2I8pX5NoamTGNuomEUFI7fcUjA==",
          "dev": true,
          "requires": {
-            "esrecurse": "^4.1.0",
-            "estraverse": "^4.1.1"
+            "@types/color-name": "^1.1.1",
+            "color-convert": "^2.0.1"
          }
        },
-        "eslint-utils": {
-          "version": "1.4.3",
-          "resolved": "https://registry.npmjs.org/eslint-utils/-/eslint-utils-1.4.3.tgz",
-          "integrity": "sha512-fbBN5W2xdY45KulGXmLHZ3c3FHfVYmKg0IrAKGOkT/464PQsx2UeIzfz1RmEci+KLm1bBaAzZAh8+/E+XAeZ8Q==",
+        "chalk": {
+          "version": "4.1.0",
+          "resolved": "https://registry.npmjs.org/chalk/-/chalk-4.1.0.tgz",
+          "integrity": "sha512-qwx12AxXe2Q5xQ43Ac//I6v5aXTipYrSESdOgzrN+9XjgEpyjpKuvSGaN4qE93f7TQTlerQQ8S+EQ0EyDoVL1A==",
          "dev": true,
          "requires": {
-            "eslint-visitor-keys": "^1.1.0"
+            "ansi-styles": "^4.1.0",
+            "supports-color": "^7.1.0"
          }
        },
+        "color-convert": {
+          "version": "2.0.1",
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+          "dev": true
+        },
+        "cross-spawn": {
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+          "resolved": "https://registry.npmjs.org/cross-spawn/-/cross-spawn-7.0.3.tgz",
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+          "dev": true,
+          "requires": {
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+            "shebang-command": "^2.0.0",
+            "which": "^2.0.1"
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+          "dev": true,
+          "requires": {
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+          }
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+          "dev": true
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+          "resolved": "https://registry.npmjs.org/levn/-/levn-0.4.1.tgz",
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+          "dev": true,
+          "requires": {
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+            "type-check": "~0.4.0"
+          }
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+          "resolved": "https://registry.npmjs.org/optionator/-/optionator-0.9.1.tgz",
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+          "dev": true,
+          "requires": {
+            "deep-is": "^0.1.3",
+            "fast-levenshtein": "^2.0.6",
+            "levn": "^0.4.1",
+            "prelude-ls": "^1.2.1",
+            "type-check": "^0.4.0",
+            "word-wrap": "^1.2.3"
+          }
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+          "version": "3.1.1",
+          "resolved": "https://registry.npmjs.org/path-key/-/path-key-3.1.1.tgz",
+          "integrity": "sha512-ojmeN0qd+y0jszEtoY48r0Peq5dwMEkIlCOu6Q5f41lfkswXuKtYrhgoTpLnyIcHm24Uhqx+5Tqm2InSwLhE6Q==",
+          "dev": true
+        },
+        "prelude-ls": {
+          "version": "1.2.1",
+          "resolved": "https://registry.npmjs.org/prelude-ls/-/prelude-ls-1.2.1.tgz",
+          "integrity": "sha512-vkcDPrRZo1QZLbn5RLGPpg/WmIQ65qoWWhcGKf/b5eplkkarX0m9z8ppCat4mlOqUsWpyNuYgO3VRyrYHSzX5g==",
+          "dev": true
+        },
        "regexpp": {
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-          "resolved": "https://registry.npmjs.org/regexpp/-/regexpp-2.0.1.tgz",
-          "integrity": "sha512-lv0M6+TkDVniA3aD1Eg0DVpfU/booSu7Eev3TDO/mZKHBfVjgCGTV4t4buppESEYDtkArYFOxTJWv6S5C+iaNw==",
+          "version": "3.1.0",
+          "resolved": "https://registry.npmjs.org/regexpp/-/regexpp-3.1.0.tgz",
+          "integrity": "sha512-ZOIzd8yVsQQA7j8GCSlPGXwg5PfmA1mrq0JP4nGhh54LaKN3xdai/vHUDu74pKwV8OxseMS65u2NImosQcSD0Q==",
          "dev": true
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        "semver": {
-          "version": "5.7.1",
-          "resolved": "https://registry.npmjs.org/semver/-/semver-5.7.1.tgz",
-          "integrity": "sha512-sauaDf/PZdVgrLTNYHRtpXa1iRiKcaebiKQ1BJdpQlWH2lCvexQdX55snPFyK7QzpudqbCI0qXFfOasHdyNDGQ==",
+          "version": "7.3.2",
+          "resolved": "https://registry.npmjs.org/semver/-/semver-7.3.2.tgz",
+          "integrity": "sha512-OrOb32TeeambH6UrhtShmF7CRDqhL6/5XpPNp2DuRH6+9QLw/orhp72j87v8Qa1ScDkvrrBNpZcDejAirJmfXQ==",
          "dev": true
+        },
+        "shebang-command": {
+          "version": "2.0.0",
+          "resolved": "https://registry.npmjs.org/shebang-command/-/shebang-command-2.0.0.tgz",
+          "integrity": "sha512-kHxr2zZpYtdmrN1qDjrrX/Z1rR1kG8Dx+gkpK1G4eXmvXswmcE1hTWBWYUzlraYw1/yZp6YuDY77YtvbN0dmDA==",
+          "dev": true,
+          "requires": {
+            "shebang-regex": "^3.0.0"
+          }
+        },
+        "shebang-regex": {
+          "version": "3.0.0",
+          "resolved": "https://registry.npmjs.org/shebang-regex/-/shebang-regex-3.0.0.tgz",
+          "integrity": "sha512-7++dFhtcx3353uBaq8DDR4NuxBetBzC7ZQOhmTQInHEd6bSrXdiEyzCvG07Z44UYdLShWUyXt5M/yhz8ekcb1A==",
+          "dev": true
+        },
+        "strip-ansi": {
+          "version": "6.0.0",
+          "resolved": "https://registry.npmjs.org/strip-ansi/-/strip-ansi-6.0.0.tgz",
+          "integrity": "sha512-AuvKTrTfQNYNIctbR1K/YGTR1756GycPsg7b9bdV9Duqur4gv6aKqHXah67Z8ImS7WEz5QVcOtlfW2rZEugt6w==",
+          "dev": true,
+          "requires": {
+            "ansi-regex": "^5.0.0"
+          }
+        },
+        "supports-color": {
+          "version": "7.1.0",
+          "resolved": "https://registry.npmjs.org/supports-color/-/supports-color-7.1.0.tgz",
+          "integrity": "sha512-oRSIpR8pxT1Wr2FquTNnGet79b3BWljqOuoW/h4oBhxJ/HUbX5nX6JSruTkvXDCFMwDPvsaTTbvMLKZWSy0R5g==",
+          "dev": true,
+          "requires": {
+            "has-flag": "^4.0.0"
+          }
+        },
+        "type-check": {
+          "version": "0.4.0",
+          "resolved": "https://registry.npmjs.org/type-check/-/type-check-0.4.0.tgz",
+          "integrity": "sha512-XleUoc9uwGXqjWwXaUTZAmzMcFZ5858QA2vvx1Ur5xIcixXIP+8LnFDgRplU30us6teqdlskFfu+ae4K79Ooew==",
+          "dev": true,
+          "requires": {
+            "prelude-ls": "^1.2.1"
+          }
+        },
+        "which": {
+          "version": "2.0.2",
+          "resolved": "https://registry.npmjs.org/which/-/which-2.0.2.tgz",
+          "integrity": "sha512-BLI3Tl1TW3Pvl70l3yq3Y64i+awpwXqsGBYWkkqMtnbXgrMD+yj7rhW0kuEDxzJaYXGjEW5ogapKNMEKNMjibA==",
+          "dev": true,
+          "requires": {
+            "isexe": "^2.0.0"
+          }
        }
      }
    },
@@ -5927,9 +6077,9 @@
      "dev": true
    },
    "eslint-scope": {
-      "version": "5.0.0",
-      "resolved": "https://registry.npmjs.org/eslint-scope/-/eslint-scope-5.0.0.tgz",
-      "integrity": "sha512-oYrhJW7S0bxAFDvWqzvMPRm6pcgcnWc4QnofCAqRTRfQC0JcwenzGglTtsLyIuuWFfkqDG9vz67cnttSd53djw==",
+      "version": "5.1.0",
+      "resolved": "https://registry.npmjs.org/eslint-scope/-/eslint-scope-5.1.0.tgz",
+      "integrity": "sha512-iiGRvtxWqgtx5m8EyQUJihBloE4EnYeGE/bz1wSPwJE6tZuJUtHlhqDM4Xj2ukE8Dyy1+HCZ4hE0fzIVMzb58w==",
      "dev": true,
      "requires": {
        "esrecurse": "^4.1.0",
@@ -5937,9 +6087,9 @@
      }
    },
    "eslint-utils": {
-      "version": "2.0.0",
-      "resolved": "https://registry.npmjs.org/eslint-utils/-/eslint-utils-2.0.0.tgz",
-      "integrity": "sha512-0HCPuJv+7Wv1bACm8y5/ECVfYdfsAm9xmVb7saeFlxjPYALefjhbYoCkBjPdPzGH8wWyTpAez82Fh3VKYEZ8OA==",
+      "version": "2.1.0",
+      "resolved": "https://registry.npmjs.org/eslint-utils/-/eslint-utils-2.1.0.tgz",
+      "integrity": "sha512-w94dQYoauyvlDc43XnGB8lU3Zt713vNChgt4EWwhXAP2XkBvndfxF0AgIqKOOasjPIPzj9JqgwkwbCYD0/V3Zg==",
      "dev": true,
      "requires": {
        "eslint-visitor-keys": "^1.1.0"
@@ -5952,14 +6102,22 @@
      "dev": true
    },
    "espree": {
-      "version": "5.0.1",
-      "resolved": "https://registry.npmjs.org/espree/-/espree-5.0.1.tgz",
-      "integrity": "sha512-qWAZcWh4XE/RwzLJejfcofscgMc9CamR6Tn1+XRXNzrvUSSbiAjGOI/fggztjIi7y9VLPqnICMIPiGyr8JaZ0A==",
+      "version": "7.1.0",
+      "resolved": "https://registry.npmjs.org/espree/-/espree-7.1.0.tgz",
+      "integrity": "sha512-dcorZSyfmm4WTuTnE5Y7MEN1DyoPYy1ZR783QW1FJoenn7RailyWFsq/UL6ZAAA7uXurN9FIpYyUs3OfiIW+Qw==",
      "dev": true,
      "requires": {
-        "acorn": "^6.0.7",
-        "acorn-jsx": "^5.0.0",
-        "eslint-visitor-keys": "^1.0.0"
+        "acorn": "^7.2.0",
+        "acorn-jsx": "^5.2.0",
+        "eslint-visitor-keys": "^1.2.0"
+      },
+      "dependencies": {
+        "eslint-visitor-keys": {
+          "version": "1.3.0",
+          "resolved": "https://registry.npmjs.org/eslint-visitor-keys/-/eslint-visitor-keys-1.3.0.tgz",
+          "integrity": "sha512-6J72N8UNa462wa/KFODt/PJ3IU60SDpC3QXC1Hjc1BXXpfL2C9R5+AU7jhe0F6GREqVMh4Juu+NY7xn+6dipUQ==",
+          "dev": true
+        }
      }
    },
    "esprima": {
@@ -6486,6 +6644,15 @@
        "path-is-absolute": "^1.0.0"
      }
    },
+    "glob-parent": {
+      "version": "5.1.1",
+      "resolved": "https://registry.npmjs.org/glob-parent/-/glob-parent-5.1.1.tgz",
+      "integrity": "sha512-FnI+VGOpnlGHWZxthPGR+QhR78fuiK0sNLkHQv+bL9fQi57lNNdquIbna/WrfROrolq8GK5Ek6BiMwqL/voRYQ==",
+      "dev": true,
+      "requires": {
+        "is-glob": "^4.0.1"
+      }
+    },
    "globals": {
      "version": "11.12.0",
      "resolved": "https://registry.npmjs.org/globals/-/globals-11.12.0.tgz",
@@ -12781,12 +12948,6 @@
      "integrity": "sha1-F0uSaHNVNP+8es5r9TpanhtcX18=",
      "dev": true
    },
-    "path-is-inside": {
-      "version": "1.0.2",
-      "resolved": "https://registry.npmjs.org/path-is-inside/-/path-is-inside-1.0.2.tgz",
-      "integrity": "sha1-NlQX3t5EQw0cEa9hAn+s8HS9/FM=",
-      "dev": true
-    },
    "path-key": {
      "version": "2.0.1",
      "resolved": "https://registry.npmjs.org/path-key/-/path-key-2.0.1.tgz",
@@ -13862,9 +14023,9 @@
      "dev": true
    },
    "strip-json-comments": {
-      "version": "2.0.1",
-      "resolved": "https://registry.npmjs.org/strip-json-comments/-/strip-json-comments-2.0.1.tgz",
-      "integrity": "sha1-PFMZQukIwml8DsNEhYwobHygpgo=",
+      "version": "3.1.0",
+      "resolved": "https://registry.npmjs.org/strip-json-comments/-/strip-json-comments-3.1.0.tgz",
+      "integrity": "sha512-e6/d0eBu7gHtdCqFt0xJr642LdToM5/cN4Qb9DbHjVx1CP5RyeM+zH7pbecEmDv/lBqb0QH+6Uqq75rxFPkM0w==",
      "dev": true
    },
    "supports-color": {
@@ -14317,6 +14478,12 @@
      "dev": true,
      "optional": true
    },
+    "v8-compile-cache": {
+      "version": "2.1.1",
+      "resolved": "https://registry.npmjs.org/v8-compile-cache/-/v8-compile-cache-2.1.1.tgz",
+      "integrity": "sha512-8OQ9CL+VWyt3JStj7HX7/ciTL2V3Rl1Wf5OL+SNTm0yK1KvtReVulksyeRnCANHHuUxHlQig+JJDlUhBt1NQDQ==",
+      "dev": true
+    },
    "v8-to-istanbul": {
      "version": "4.1.4",
      "resolved": "https://registry.npmjs.org/v8-to-istanbul/-/v8-to-istanbul-4.1.4.tgz",
--- a/package.json
+++ b/package.json
@@ -1,8 +1,8 @@
 {
-  "name": "pr-changed-files-filter",
+  "name": "paths-filter",
  "version": "1.0.0",
  "private": true,
-  "description": "Enables conditional execution of workflow job steps considering which files are modified by a pull request.",
+  "description": "Execute your workflow steps only if relevant files are modified.",
  "main": "lib/main.js",
  "scripts": {
    "build": "tsc",
@@ -36,9 +36,9 @@
    "@types/js-yaml": "^3.12.4",
    "@types/minimatch": "^3.0.3",
    "@types/node": "^14.0.5",
-    "@typescript-eslint/parser": "^3.0.0",
+    "@typescript-eslint/parser": "^3.3.0",
    "@zeit/ncc": "^0.22.3",
-    "eslint": "^5.16.0",
+    "eslint": "^7.3.0",
    "eslint-plugin-github": "^2.0.0",
    "eslint-plugin-jest": "^22.21.0",
    "jest": "^26.0.1",
--- a/src/exec.ts
+++ b/src/exec.ts
@@ -0,0 +1,21 @@
+import {exec as execImpl, ExecOptions} from '@actions/exec'
+
+// Wraps original exec() function
+// Returns exit code and whole stdout/stderr
+export default async function exec(commandLine: string, args?: string[], options?: ExecOptions): Promise<ExecResult> {
+  options = options || {}
+  let stdout = ''
+  let stderr = ''
+  options.listeners = {
+    stdout: (data: Buffer) => (stdout += data.toString()),
+    stderr: (data: Buffer) => (stderr += data.toString())
+  }
+  const code = await execImpl(commandLine, args, options)
+  return {code, stdout, stderr}
+}
+
+export interface ExecResult {
+  code: number
+  stdout: string
+  stderr: string
+}
--- a/src/file.ts
+++ b/src/file.ts
@@ -0,0 +1,13 @@
+export interface File {
+  filename: string
+  status: ChangeStatus
+}
+
+export enum ChangeStatus {
+  Added = 'added',
+  Copied = 'copied',
+  Deleted = 'deleted',
+  Modified = 'modified',
+  Renamed = 'renamed',
+  Unmerged = 'unmerged'
+}
--- a/src/filter.ts
+++ b/src/filter.ts
@@ -1,42 +1,109 @@
 import * as jsyaml from 'js-yaml'
 import * as minimatch from 'minimatch'
+import {File, ChangeStatus} from './file'

-export default class Filter {
-  rules: {[key: string]: minimatch.IMinimatch[]} = {}
+// Type definition of object we expect to load from YAML
+interface FilterYaml {
+  [name: string]: FilterItemYaml
+}
+type FilterItemYaml =
+  | string // Filename pattern, e.g. "path/to/*.js"
+  | {[changeTypes: string]: string} // Change status and filename, e.g. added|modified: "path/to/*.js"
+  | FilterItemYaml[] // Supports referencing another rule via YAML anchor

-  constructor(yaml: string) {
-    const doc = jsyaml.safeLoad(yaml)
-    if (typeof doc !== 'object') {
-      this.throwInvalidFormatError()
-    }
+// Minimatch options used in all matchers
+const MinimatchOptions: minimatch.IOptions = {
+  dot: true
+}

-    const opts: minimatch.IOptions = {
-      dot: true
-    }
+// Internal representation of one item in named filter rule
+// Created as simplified form of data in FilterItemYaml
+interface FilterRuleItem {
+  status?: ChangeStatus[] // Required change status of the matched files
+  matcher: minimatch.IMinimatch // Matches the filename
+}

-    for (const name of Object.keys(doc)) {
-      const patterns = doc[name] as string[]
-      if (!Array.isArray(patterns)) {
-        this.throwInvalidFormatError()
-      }
-      if (!patterns.every(x => typeof x === 'string')) {
-        this.throwInvalidFormatError()
-      }
-      this.rules[name] = patterns.map(x => new minimatch.Minimatch(x, opts))
+export interface FilterResults {
+  [key: string]: File[]
+}
+
+export class Filter {
+  rules: {[key: string]: FilterRuleItem[]} = {}
+
+  // Creates instance of Filter and load rules from YAML if it's provided
+  constructor(yaml?: string) {
+    if (yaml) {
+      this.load(yaml)
    }
  }

-  // Returns dictionary with match result per rules group
-  match(paths: string[]): {[key: string]: boolean} {
-    const result: {[key: string]: boolean} = {}
+  // Load rules from YAML string
+  load(yaml: string): void {
+    if (!yaml) {
+      return
+    }
+
+    const doc = jsyaml.safeLoad(yaml) as FilterYaml
+    if (typeof doc !== 'object') {
+      this.throwInvalidFormatError('Root element is not an object')
+    }
+
+    for (const [key, item] of Object.entries(doc)) {
+      this.rules[key] = this.parseFilterItemYaml(item)
+    }
+  }
+
+  match(files: File[]): FilterResults {
+    const result: FilterResults = {}
    for (const [key, patterns] of Object.entries(this.rules)) {
-      const match = paths.some(fileName => patterns.some(rule => rule.match(fileName)))
-      result[key] = match
+      result[key] = files.filter(file => this.isMatch(file, patterns))
    }
    return result
  }

-  private throwInvalidFormatError(): never {
-    throw new Error('Invalid filter YAML format: Expected dictionary of string arrays')
+  private isMatch(file: File, patterns: FilterRuleItem[]): boolean {
+    return patterns.some(
+      rule => (rule.status === undefined || rule.status.includes(file.status)) && rule.matcher.match(file.filename)
+    )
+  }
+
+  private parseFilterItemYaml(item: FilterItemYaml): FilterRuleItem[] {
+    if (Array.isArray(item)) {
+      return flat(item.map(i => this.parseFilterItemYaml(i)))
+    }
+
+    if (typeof item === 'string') {
+      return [{status: undefined, matcher: new minimatch.Minimatch(item, MinimatchOptions)}]
+    }
+
+    if (typeof item === 'object') {
+      return Object.entries(item).map(([key, pattern]) => {
+        if (typeof key !== 'string' || typeof pattern !== 'string') {
+          this.throwInvalidFormatError(
+            `Expected [key:string]= pattern:string, but [${key}:${typeof key}]= ${pattern}:${typeof pattern} found`
+          )
+        }
+        return {
+          status: key
+            .split('|')
+            .map(x => x.trim())
+            .filter(x => x.length > 0)
+            .map(x => x.toLowerCase()) as ChangeStatus[],
+          matcher: new minimatch.Minimatch(pattern, MinimatchOptions)
+        }
+      })
+    }
+
+    this.throwInvalidFormatError(`Unexpected element type '${typeof item}'`)
+  }
+
+  private throwInvalidFormatError(message: string): never {
+    throw new Error(`Invalid filter YAML format: ${message}.`)
  }
 }
+
+// Creates a new array with all sub-array elements concatenated
+// In future could be replaced by Array.prototype.flat (supported on Node.js 11+)
+function flat<T>(arr: T[][]): T[] {
+  return arr.reduce((acc, val) => acc.concat(val), [])
+}
--- a/src/git.ts
+++ b/src/git.ts
@@ -1,26 +1,185 @@
-import {exec} from '@actions/exec'
+import exec from './exec'
+import * as core from '@actions/core'
+import {File, ChangeStatus} from './file'

-export async function fetchBranch(base: string): Promise<void> {
-  const exitCode = await exec('git', ['fetch', '--depth=1', 'origin', base])
-  if (exitCode !== 0) {
-    throw new Error(`Fetching branch ${base} failed, exiting`)
+export const NULL_SHA = '0000000000000000000000000000000000000000'
+
+export async function getChangesInLastCommit(): Promise<File[]> {
+  core.startGroup(`Change detection in last commit`)
+  let output = ''
+  try {
+    output = (await exec('git', ['log', '--format=', '--no-renames', '--name-status', '-z', '-n', '1'])).stdout
+  } finally {
+    fixStdOutNullTermination()
+    core.endGroup()
  }
+
+  return parseGitDiffOutput(output)
 }

-export async function getChangedFiles(base: string): Promise<string[]> {
-  let output = ''
-  const exitCode = await exec('git', ['diff-index', '--name-only', base], {
-    listeners: {
-      stdout: (data: Buffer) => (output += data.toString())
-    }
-  })
+export async function getChanges(ref: string): Promise<File[]> {
+  if (!(await hasCommit(ref))) {
+    // Fetch single commit
+    core.startGroup(`Fetching ${ref} from origin`)
+    await exec('git', ['fetch', '--depth=1', '--no-tags', '--no-auto-gc', 'origin', ref])
+    core.endGroup()
+  }

-  if (exitCode !== 0) {
-    throw new Error(`Couldn't determine changed files, exiting`)
+  // Get differences between ref and HEAD
+  core.startGroup(`Change detection ${ref}..HEAD`)
+  let output = ''
+  try {
+    // Two dots '..' change detection - directly compares two versions
+    output = (await exec('git', ['diff', '--no-renames', '--name-status', '-z', `${ref}..HEAD`])).stdout
+  } finally {
+    fixStdOutNullTermination()
+    core.endGroup()
+  }
+
+  return parseGitDiffOutput(output)
+}
+
+export async function getChangesSinceMergeBase(ref: string, initialFetchDepth: number): Promise<File[]> {
+  if (!(await hasCommit(ref))) {
+    // Fetch and add base branch
+    core.startGroup(`Fetching ${ref}`)
+    try {
+      await exec('git', ['fetch', `--depth=${initialFetchDepth}`, '--no-tags', 'origin', `${ref}:${ref}`])
+    } finally {
+      core.endGroup()
+    }
+  }
+
+  async function hasMergeBase(): Promise<boolean> {
+    return (await exec('git', ['merge-base', ref, 'HEAD'], {ignoreReturnCode: true})).code === 0
+  }
+
+  async function countCommits(): Promise<number> {
+    return (await getNumberOfCommits('HEAD')) + (await getNumberOfCommits(ref))
+  }
+
+  core.startGroup(`Searching for merge-base with ${ref}`)
+  // Fetch more commits until merge-base is found
+  if (!(await hasMergeBase())) {
+    let deepen = initialFetchDepth
+    let lastCommitsCount = await countCommits()
+    do {
+      await exec('git', ['fetch', `--deepen=${deepen}`, '--no-tags', '--no-auto-gc'])
+      const count = await countCommits()
+      if (count <= lastCommitsCount) {
+        core.info('No merge base found - all files will be listed as added')
+        core.endGroup()
+        return await listAllFilesAsAdded()
+      }
+      lastCommitsCount = count
+      deepen = Math.min(deepen * 2, Number.MAX_SAFE_INTEGER)
+    } while (!(await hasMergeBase()))
+  }
+  core.endGroup()
+
+  // Get changes introduced on HEAD compared to ref
+  core.startGroup(`Change detection ${ref}...HEAD`)
+  let output = ''
+  try {
+    // Three dots '...' change detection - finds merge-base and compares against it
+    output = (await exec('git', ['diff', '--no-renames', '--name-status', '-z', `${ref}...HEAD`])).stdout
+  } finally {
+    fixStdOutNullTermination()
+    core.endGroup()
+  }
+
+  return parseGitDiffOutput(output)
+}
+
+export function parseGitDiffOutput(output: string): File[] {
+  const tokens = output.split('\u0000').filter(s => s.length > 0)
+  const files: File[] = []
+  for (let i = 0; i + 1 < tokens.length; i += 2) {
+    files.push({
+      status: statusMap[tokens[i]],
+      filename: tokens[i + 1]
+    })
+  }
+  return files
+}
+
+export async function listAllFilesAsAdded(): Promise<File[]> {
+  core.startGroup('Listing all files tracked by git')
+  let output = ''
+  try {
+    output = (await exec('git', ['ls-files', '-z'])).stdout
+  } finally {
+    fixStdOutNullTermination()
+    core.endGroup()
  }

  return output
-    .split('\n')
-    .map(s => s.trim())
+    .split('\u0000')
    .filter(s => s.length > 0)
+    .map(path => ({
+      status: ChangeStatus.Added,
+      filename: path
+    }))
+}
+
+export async function getCurrentRef(): Promise<string> {
+  core.startGroup(`Determining current ref`)
+  try {
+    const branch = (await exec('git', ['branch', '--show-current'])).stdout.trim()
+    if (branch) {
+      return branch
+    }
+
+    const describe = await exec('git', ['describe', '--tags', '--exact-match'], {ignoreReturnCode: true})
+    if (describe.code === 0) {
+      return describe.stdout.trim()
+    }
+
+    return (await exec('git', ['rev-parse', 'HEAD'])).stdout.trim()
+  } finally {
+    core.endGroup()
+  }
+}
+
+export function getShortName(ref: string): string {
+  if (!ref) return ''
+
+  const heads = 'refs/heads/'
+  const tags = 'refs/tags/'
+
+  if (ref.startsWith(heads)) return ref.slice(heads.length)
+  if (ref.startsWith(tags)) return ref.slice(tags.length)
+
+  return ref
+}
+
+async function hasCommit(ref: string): Promise<boolean> {
+  core.startGroup(`Checking if commit for ${ref} is locally available`)
+  try {
+    return (await exec('git', ['cat-file', '-e', `${ref}^{commit}`], {ignoreReturnCode: true})).code === 0
+  } finally {
+    core.endGroup()
+  }
+}
+
+async function getNumberOfCommits(ref: string): Promise<number> {
+  const output = (await exec('git', ['rev-list', `--count`, ref])).stdout
+  const count = parseInt(output)
+  return isNaN(count) ? 0 : count
+}
+
+function fixStdOutNullTermination(): void {
+  // Previous command uses NULL as delimiters and output is printed to stdout.
+  // We have to make sure next thing written to stdout will start on new line.
+  // Otherwise things like ::set-output wouldn't work.
+  core.info('')
+}
+
+const statusMap: {[char: string]: ChangeStatus} = {
+  A: ChangeStatus.Added,
+  C: ChangeStatus.Copied,
+  D: ChangeStatus.Deleted,
+  M: ChangeStatus.Modified,
+  R: ChangeStatus.Renamed,
+  U: ChangeStatus.Unmerged
 }
--- a/src/main.ts
+++ b/src/main.ts
@@ -3,28 +3,36 @@ import * as core from '@actions/core'
 import * as github from '@actions/github'
 import {Webhooks} from '@octokit/webhooks'

-import Filter from './filter'
+import {Filter, FilterResults} from './filter'
+import {File, ChangeStatus} from './file'
 import * as git from './git'
+import shellEscape from './shell-escape'
+
+type ExportFormat = 'none' | 'json' | 'shell'

 async function run(): Promise<void> {
  try {
+    const workingDirectory = core.getInput('working-directory', {required: false})
+    if (workingDirectory) {
+      process.chdir(workingDirectory)
+    }
+
    const token = core.getInput('token', {required: false})
+    const base = core.getInput('base', {required: false})
    const filtersInput = core.getInput('filters', {required: true})
    const filtersYaml = isPathInput(filtersInput) ? getConfigFileContent(filtersInput) : filtersInput
+    const listFiles = core.getInput('list-files', {required: false}).toLowerCase() || 'none'
+    const initialFetchDepth = parseInt(core.getInput('initial-fetch-depth', {required: false})) || 10

-    if (github.context.eventName !== 'pull_request') {
-      core.setFailed('This action can be triggered only by pull_request event')
+    if (!isExportFormat(listFiles)) {
+      core.setFailed(`Input parameter 'list-files' is set to invalid value '${listFiles}'`)
      return
    }

-    const pr = github.context.payload.pull_request as Webhooks.WebhookPayloadPullRequestPullRequest
    const filter = new Filter(filtersYaml)
-    const files = token ? await getChangedFilesFromApi(token, pr) : await getChangedFilesFromGit(pr)
-
-    const result = filter.match(files)
-    for (const key in result) {
-      core.setOutput(key, String(result[key]))
-    }
+    const files = await getChangedFiles(token, base, initialFetchDepth)
+    const results = filter.match(files)
+    exportResults(results, listFiles)
  } catch (error) {
    core.setFailed(error.message)
  }
@@ -46,23 +54,75 @@ function getConfigFileContent(configPath: string): string {
  return fs.readFileSync(configPath, {encoding: 'utf8'})
 }

-// Fetch base branch and use `git diff` to determine changed files
-async function getChangedFilesFromGit(pullRequest: Webhooks.WebhookPayloadPullRequestPullRequest): Promise<string[]> {
-  core.debug('Fetching base branch and using `git diff-index` to determine changed files')
-  const baseRef = pullRequest.base.ref
-  await git.fetchBranch(baseRef)
-  return await git.getChangedFiles(pullRequest.base.sha)
+async function getChangedFiles(token: string, base: string, initialFetchDepth: number): Promise<File[]> {
+  if (github.context.eventName === 'pull_request' || github.context.eventName === 'pull_request_target') {
+    const pr = github.context.payload.pull_request as Webhooks.WebhookPayloadPullRequestPullRequest
+    if (token) {
+      return await getChangedFilesFromApi(token, pr)
+    }
+    core.info('Github token is not available - changes will be detected from PRs merge commit')
+    return await git.getChangesInLastCommit()
+  } else if (github.context.eventName === 'push') {
+    return getChangedFilesFromPush(base, initialFetchDepth)
+  } else {
+    throw new Error('This action can be triggered only by pull_request, pull_request_target or push event')
+  }
+}
+
+async function getChangedFilesFromPush(base: string, initialFetchDepth: number): Promise<File[]> {
+  const push = github.context.payload as Webhooks.WebhookPayloadPush
+  const defaultRef = push.repository?.default_branch
+
+  const pushRef =
+    git.getShortName(push.ref) ||
+    (core.warning(`'ref' field is missing in PUSH event payload - using current branch, tag or commit SHA`),
+    await git.getCurrentRef())
+
+  const baseRef = git.getShortName(base) || defaultRef
+  if (!baseRef) {
+    throw new Error(
+      "This action requires 'base' input to be configured or 'repository.default_branch' to be set in the event payload"
+    )
+  }
+
+  // If base references same branch it was pushed to,
+  // we will do comparison against the previously pushed commit
+  if (baseRef === pushRef) {
+    if (!push.before) {
+      core.warning(`'before' field is missing in PUSH event payload - changes will be detected from last commit`)
+      return await git.getChangesInLastCommit()
+    }
+
+    // If there is no previously pushed commit,
+    // we will do comparison against the default branch or return all as added
+    if (push.before === git.NULL_SHA) {
+      if (defaultRef && baseRef !== defaultRef) {
+        core.info(`First push of a branch detected - changes will be detected against the default branch ${defaultRef}`)
+        return await git.getChangesSinceMergeBase(defaultRef, initialFetchDepth)
+      } else {
+        core.info('Initial push detected - all files will be listed as added')
+        return await git.listAllFilesAsAdded()
+      }
+    }
+
+    core.info(`Changes will be detected against the last previously pushed commit on same branch (${pushRef})`)
+    return await git.getChanges(push.before)
+  }
+
+  // Changes introduced by current branch against the base branch
+  core.info(`Changes will be detected against the branch ${baseRef}`)
+  return await git.getChangesSinceMergeBase(baseRef, initialFetchDepth)
 }

 // Uses github REST api to get list of files changed in PR
 async function getChangedFilesFromApi(
  token: string,
  pullRequest: Webhooks.WebhookPayloadPullRequestPullRequest
-): Promise<string[]> {
-  core.debug('Fetching list of modified files from Github API')
+): Promise<File[]> {
+  core.info(`Fetching list of changed files for PR#${pullRequest.number} from Github API`)
  const client = new github.GitHub(token)
  const pageSize = 100
-  const files: string[] = []
+  const files: File[] = []
  for (let page = 0; page * pageSize < pullRequest.changed_files; page++) {
    const response = await client.pulls.listFiles({
      owner: github.context.repo.owner,
@@ -72,11 +132,68 @@ async function getChangedFilesFromApi(
      per_page: pageSize
    })
    for (const row of response.data) {
-      files.push(row.filename)
+      // There's no obvious use-case for detection of renames
+      // Therefore we treat it as if rename detection in git diff was turned off.
+      // Rename is replaced by delete of original filename and add of new filename
+      if (row.status === ChangeStatus.Renamed) {
+        files.push({
+          filename: row.filename,
+          status: ChangeStatus.Added
+        })
+        files.push({
+          // 'previous_filename' for some unknown reason isn't in the type definition or documentation
+          filename: (<any>row).previous_filename as string,
+          status: ChangeStatus.Deleted
+        })
+      } else {
+        files.push({
+          filename: row.filename,
+          status: row.status as ChangeStatus
+        })
+      }
    }
  }

  return files
 }

+function exportResults(results: FilterResults, format: ExportFormat): void {
+  core.info('Results:')
+  for (const [key, files] of Object.entries(results)) {
+    const value = files.length > 0
+    core.startGroup(`Filter ${key} = ${value}`)
+    if (files.length > 0) {
+      core.info('Matching files:')
+      for (const file of files) {
+        core.info(`${file.filename} [${file.status}]`)
+      }
+    } else {
+      core.info('Matching files: none')
+    }
+
+    core.setOutput(key, value)
+    if (format !== 'none') {
+      const filesValue = serializeExport(files, format)
+      core.setOutput(`${key}_files`, filesValue)
+    }
+  }
+  core.endGroup()
+}
+
+function serializeExport(files: File[], format: ExportFormat): string {
+  const fileNames = files.map(file => file.filename)
+  switch (format) {
+    case 'json':
+      return JSON.stringify(fileNames)
+    case 'shell':
+      return fileNames.map(shellEscape).join(' ')
+    default:
+      return ''
+  }
+}
+
+function isExportFormat(value: string): value is ExportFormat {
+  return value === 'none' || value === 'shell' || value === 'json'
+}
+
 run()
--- a/src/shell-escape.ts
+++ b/src/shell-escape.ts
@@ -0,0 +1,7 @@
+// Credits to https://github.com/xxorax/node-shell-escape
+
+export default function shellEscape(value: string): string {
+  return `'${value.replace(/'/g, "'\\''")}'`
+    .replace(/^(?:'')+/g, '') // unduplicate single-quote at the beginning
+    .replace(/\\'''/g, "\\'") // remove non-escaped single-quote if there are enclosed between 2 escaped
+}
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -1,6 +1,6 @@
 {
  "compilerOptions": {
-    "target": "es6",                          /* Specify ECMAScript target version: 'ES3' (default), 'ES5', 'ES2015', 'ES2016', 'ES2017', 'ES2018', 'ES2019' or 'ESNEXT'. */
+    "target": "es2019",                          /* Specify ECMAScript target version: 'ES3' (default), 'ES5', 'ES2015', 'ES2016', 'ES2017', 'ES2018', 'ES2019' or 'ESNEXT'. */
    "module": "commonjs",                     /* Specify module code generation: 'none', 'commonjs', 'amd', 'system', 'umd', 'es2015', or 'ESNext'. */
    "outDir": "./lib",                        /* Redirect output structure to the directory. */
    "rootDir": "./src",                       /* Specify the root directory of input files. Use to control the output directory structure with --outDir. */
Author	SHA1	Message	Date
Michal Dorner	ff5bb057bf	v2.4.0 - support local execution with act + allow tags (#40 ) * Avoid code repetition with exec() and output listeners * Improve behavior for new branches and when it's running in ACT * Detect parent commit only if needed * Fix parent commit detection for initial commit * Improve logging * Improve current ref detection * Fix issue when base is a already fetched tag * Fix issue when base is a already fetched tag * Update README * Document usage with act * Use `git log` to get changes in latest commit * Disable other output for `git log` * get short name from base ref + improve loggig * update CHANGELOG	2020-09-30 00:32:49 +02:00
Michal Dorner	d9e86af7c0	Small improvement to project description	2020-09-14 18:49:18 +02:00
Michal Dorner	adb239d623	Add hint to use fetch-depth for feature branch workdlow	2020-09-14 18:09:37 +02:00
Michal Dorner	1f7b23edeb	Merge pull request #38 from dorny/develop Release v 2.3.0	2020-09-14 17:26:56 +02:00
Michal Dorner	bfc5803f5e	Add working-directory PR to changelog	2020-09-14 17:22:51 +02:00
Michal Dorner	b4f32c4f08	Reworked README for v2.3 release (#37 )	2020-09-14 17:19:32 +02:00
Michal Dorner	81c90ccae8	Change detection using git "three dot" diff (#35 ) * Rework change detection via `git diff` Previous implementation performed simple diff between two versions. New implementation fetches on demand more commits to have the merge base between two branches. Now it will detect only changes introduced by branch that was pushed, instead of mixing with changes introduced meanwhile on the base branch.	2020-09-01 22:47:38 +02:00
Michal Dorner	3f845744aa	Export files matching rules (#32 ) * Export files matching rules * Improve debug output * Fix PR test workflow * Always quote output path + fix PR test * Use proper single quote escaping in workflow file * Improve error handling and docs for list-files input parameter	2020-08-30 21:18:14 +02:00
Michal Dorner	483986d0a7	Merge branch 'master' into develop	2020-08-14 22:03:31 +02:00
Michal Dorner	3b817c9974	Add support for pull_request_target (#30 ) Complements previous commit: - adds modified index.js - bumps version to 2.2.1	2020-08-13 21:55:56 +02:00
Rob Dodson	b365bd8768	Update main.ts (#29 ) Add support for the new `pull_request_target` event. https://docs.github.com/en/actions/reference/events-that-trigger-workflows#pull_request_target	2020-08-13 21:44:57 +02:00
Michal Dorner	f34047f516	Export changed files grouped by change status (#23 )	2020-08-04 20:57:29 +02:00
Michal Dorner	1ff702da35	Extend filter syntax with optional specification of file status: add, modified, deleted (#22 ) * Add support for specification of change type (add,modified,delete) * Use NULL as separator in git-diff command output * Improve PR test workflow * Fix the workflow file	2020-08-04 20:57:29 +02:00
Michal Dorner	caef9bef1f	Add working-directory input (#21 )	2020-08-04 20:57:29 +02:00
Michal Dorner	14dd70c742	Add develop branch to PR verification	2020-08-04 20:57:29 +02:00
Daksh Shah	e1ae9889cb	Fix multiple jobs workflow example (#25 )	2020-07-16 12:33:30 +02:00
Michal Dorner	83deb9f037	Improve change detection for feature branches (#16 ) * Detect changes against configured base branch * Update README and action.yml * Add job.outputs example * Update CHANGELOG	2020-06-24 21:53:31 +02:00
Michal Dorner	7d201829e2	Support reusable paths blocks via yaml anchors (#13 ) * Add support for nested arrays of path expressions * Remove pull_request trigger type options Default value is fine: opened, synchronize, reopened * Add CHANGELOG * Update README	2020-06-19 23:39:06 +02:00
Michal Dorner	4eb15bc267	Update README Add links to pull_request / push events that trigger workflows	2020-06-15 22:15:38 +02:00
Michal Dorner	9ef7936e79	Fix URL in README	2020-06-15 21:57:00 +02:00
Michal Dorner	affb29871a	Support push event (#10 ) * Support triggering from push event * Add self-test to build workflow * Update action metadata	2020-06-15 21:49:10 +02:00
Tonye Jack	910e8b1235	Update README.md (#11 ) * Update README.md * Update version	2020-06-14 23:04:35 +02:00