Verify correct generated files in SCM

Author: bindreams

.github/actions/ensure-no-diff/action.yaml

@@ -0,0 +1,38 @@
+name: Ensure no changes to tracked files
+description: Detect any changes to tracked files and fail the forkflow.
+inputs:
+  post-pr-comment:
+    description: Post a comment with changes (only on pull requests)
+    required: false
+    default: true
+  comment-header:
+    description: Header for the PR comment
+    required: false
+    default: "Tracked files have changed while running ${{ github.job.name }}:"
+  comment-footer:
+    description: Footer for the PR comment
+    required: false
+    default: ""
+runs:
+  using: composite
+  steps:
+    - name: git diff
+      id: git-diff
+      uses: mathiasvr/command-output@v2
+      with:
+        shell: bash
+        run: git diff --diff-algorithm=histogram --exit-code
+
+    - name: Post PR comment
+      if: >-
+        failure() &&
+        github.event_name == 'pull_request' &&
+        inputs.post-pr-comment == 'true'
+      uses: thollander/actions-comment-pull-request@v3
+      with:
+        comment-tag: ${{ github.job }}
+        message: |
+          ${{ inputs.comment-header }}
+          ```diff
+          ${{ steps.git-diff.outputs.stdout }}```
+          ${{ inputs.comment-footer }}

.github/workflows/build.yaml

@@ -33,6 +33,9 @@ jobs:
           name: package-sdist
           path: dist/*.tar.gz
 
+      - name: Ensure no changes to tracked files
+        uses: ./.github/actions/ensure-no-diff
+
   wheels:
     name: Binary wheels
     runs-on: ${{ matrix.os }}
@@ -73,3 +76,6 @@ jobs:
         with:
           name: package-wheels-${{matrix.os}}
           path: ./wheelhouse/*.whl
+
+      - name: Ensure no changes to tracked files
+        uses: ./.github/actions/ensure-no-diff