Add commit hash in the primer comment (#6783)

Co-authored-by: Pierre Sassoulas <pierre.sassoulas@gmail.com>

.github/workflows/primer_comment.yaml

@@ -111,7 +111,10 @@ jobs:
       - name: Compare outputs
         run: |
           . venv/bin/activate
-          python tests/primer/primer_tool.py compare --base-file=output_${{ steps.python.outputs.python-version }}_main.txt --new-file=output_${{ steps.python.outputs.python-version }}_pr.txt
+          python tests/primer/primer_tool.py compare \
+          --commit=${{ github.event.workflow_run.head_sha }} \
+          --base-file=output_${{ steps.python.outputs.python-version }}_main.txt \
+          --new-file=output_${{ steps.python.outputs.python-version }}_pr.txt
       - name: Post comment
         id: post-comment
         uses: actions/github-script@v6

tests/primer/primer_tool.py

@@ -79,6 +79,11 @@ def __init__(self, json_path: Path) -> None:
             required=True,
             help="Location of output file of the new run.",
         )
+        compare_parser.add_argument(
+            "--commit",
+            required=True,
+            help="Commit hash of the PR commit being checked.",
+        )
 
         # Storing arguments
         self.config = self._argument_parser.parse_args()
@@ -256,6 +261,8 @@ def _create_comment(
                 "🤖 **Effect of this PR on checked open source code:** 🤖\n\n" + comment
             )
 
+        comment += f"*This comment was generated for commit {self.config.commit}*"
+
         with open(PRIMER_DIRECTORY / "comment.txt", "w", encoding="utf-8") as f:
             f.write(comment)