feat: add support for excluding symlinks and fix bug with commit not found (#2770)

Author: jackton1

.github/workflows/test.yml

@@ -275,6 +275,113 @@ jobs:
         shell:
           bash
 
+  test-skip-same-base-and-commit-sha:
+    name: Test changed-files skip same base and commit sha
+    runs-on: ubuntu-latest
+    needs: build
+    if: needs.build.outputs.files_changed != 'true'
+    permissions:
+      contents: read
+
+    steps:
+      - name: Checkout branch
+        uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8 # v6.0.1
+        with:
+          repository: ${{ github.event.pull_request.head.repo.full_name }}
+          fetch-depth: 0
+
+      - name: Download build assets
+        uses: actions/download-artifact@37930b1c2abaa49bbe596cd826c3c89aef350131 # v7.0.0
+        with:
+          name: build-assets
+
+      - name: Get head SHA
+        id: head-sha
+        run: |
+          echo "sha=$(git rev-parse HEAD)" >> "$GITHUB_OUTPUT"
+        shell:
+          bash
+
+      - name: Run changed-files with same base and commit sha
+        id: changed-files
+        uses: ./
+        with:
+          base_sha: ${{ steps.head-sha.outputs.sha }}
+          sha: ${{ steps.head-sha.outputs.sha }}
+          skip_same_sha: true
+
+      - name: Verify empty outputs
+        if: steps.changed-files.outputs.all_changed_files_count != '0' || steps.changed-files.outputs.any_changed != 'false'
+        run: |
+          echo "Expected empty outputs; got count=${{ steps.changed-files.outputs.all_changed_files_count }} any_changed=${{ steps.changed-files.outputs.any_changed }}"
+          exit 1
+        shell:
+          bash
+
+      - name: Show output
+        run: |
+          echo '${{ toJSON(steps.changed-files.outputs) }}'
+        shell:
+          bash
+
+  test-exclude-symlinks:
+    name: Test changed-files exclude symlinks
+    runs-on: ubuntu-latest
+    needs: build
+    if: needs.build.outputs.files_changed != 'true'
+    permissions:
+      contents: read
+
+    steps:
+      - name: Checkout branch
+        uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8 # v6.0.1
+        with:
+          repository: ${{ github.event.pull_request.head.repo.full_name }}
+          fetch-depth: 0
+
+      - name: Download build assets
+        uses: actions/download-artifact@37930b1c2abaa49bbe596cd826c3c89aef350131 # v7.0.0
+        with:
+          name: build-assets
+
+      - name: Run changed-files without symlink exclusion
+        id: changed-files-symlink-included
+        uses: ./
+        with:
+          base_sha: 955f38aa4f30f1ec92d08049b26e6d736ffea013
+          sha: ddde96a55848a649c09322c7094b22ef4b4abe23
+
+      - name: Verify symlink is present
+        if: "!contains(steps.changed-files-symlink-included.outputs.added_files, 'test/symlink-to-target')"
+        run: |
+          echo "Expected symlink to be present in added_files; got ${{ steps.changed-files-symlink-included.outputs.added_files }}"
+          exit 1
+        shell:
+          bash
+
+      - name: Run changed-files excluding symlinks
+        id: changed-files-symlink-excluded
+        uses: ./
+        with:
+          base_sha: 955f38aa4f30f1ec92d08049b26e6d736ffea013
+          sha: ddde96a55848a649c09322c7094b22ef4b4abe23
+          exclude_symlinks: true
+
+      - name: Verify symlink is excluded
+        if: "contains(steps.changed-files-symlink-excluded.outputs.added_files, 'test/symlink-to-target') || contains(steps.changed-files-symlink-excluded.outputs.all_changed_files, 'test/symlink-to-target')"
+        run: |
+          echo "Expected symlink to be excluded; got added=${{ steps.changed-files-symlink-excluded.outputs.added_files }} all=${{ steps.changed-files-symlink-excluded.outputs.all_changed_files }}"
+          exit 1
+        shell:
+          bash
+
+      - name: Show output
+        run: |
+          echo '${{ toJSON(steps.changed-files-symlink-included.outputs) }}'
+          echo '${{ toJSON(steps.changed-files-symlink-excluded.outputs) }}'
+        shell:
+          bash
+
   test-using-branch-names-for-base-sha-and-sha-inputs:
     name: Test using branch names for base_sha and sha inputs
     runs-on: ubuntu-latest

README.md

@@ -412,6 +412,16 @@ Support this project with a :star:
     # Default: "false"
     exclude_submodules: ''
 
+    # Exclude symlinks from changed files.
+    # Type: boolean
+    # Default: "false"
+    exclude_symlinks: ''
+
+    # Do not fail when base and head SHAs are identical.
+    # Type: boolean
+    # Default: "false"
+    skip_same_sha: ''
+
     # Fail when the initial diff 
     # fails. 
     # Type: boolean

action.yml

@@ -227,6 +227,14 @@ inputs:
     description: "Exclude changes to submodules."
     required: false
     default: "false"
+  exclude_symlinks:
+    description: "Exclude symlinks from changed files."
+    required: false
+    default: "false"
+  skip_same_sha:
+    description: "Do not fail when base and head SHAs are identical."
+    required: false
+    default: "false"
   fetch_missing_history_max_retries:
     description: "Maximum number of retries to fetch missing history."
     required: false