ci: fix benchmarks status reporting (#512)

.github/workflows/cicd.yml

@@ -98,9 +98,14 @@ jobs:
           invoke release --dry-run
       - name: Benchmark
         if: github.event_name == 'pull_request'
+        env:
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          # Github pull request event has the merge commit as the HEAD on checkout
+          # https://github.com/actions/checkout/issues/261
+          COMMIT_SHA: ${{ github.event.after }}
         run: |
           . $VENV/bin/activate
-          invoke benchmark
+          invoke benchmark --report
   release:
     name: Release
     runs-on: ubuntu-latest
@@ -137,6 +142,7 @@ jobs:
       - name: Benchmark
         env:
           GH_TOKEN: ${{ secrets.TOPHAT_BOT_GH_TOKEN }}
+          COMMIT_SHA: ${{ env.GITHUB_SHA }}
         run: |
           . $VENV/bin/activate
           invoke benchmark --report

benchmarks/__init__.py

@@ -45,7 +45,7 @@ def get_commit(github: "Github") -> "Commit":
     """
     Get current commit the github ci run is for
     """
-    github_sha = get_req_env("GITHUB_SHA")
+    github_sha = get_req_env("COMMIT_SHA")
     return github.get_repo(GH_REPO).get_commit(github_sha)
 
 
@@ -63,7 +63,7 @@ def get_target_url() -> str:
     """
     repo_url = f"https://github.com/{GH_REPO}"
     all_results_url = f"{repo_url}/tree/{GH_BENCH_BRANCH}/{GH_BENCH_FILE_PATH}"
-    commit_sha = get_req_env("GITHUB_SHA")
+    commit_sha = get_req_env("COMMIT_SHA")
     return all_results_url + (f"/{commit_sha}" if commit_sha else "")
 
 
@@ -102,7 +102,7 @@ def measure_perf(
     if not github:
         return
     repo = github.get_repo(GH_REPO)
-    commit_sha = get_req_env("GITHUB_SHA")
+    commit_sha = get_req_env("COMMIT_SHA")
     with open(BENCH_PERF_FILE, "r", encoding="utf-8") as bench_file:
         try:
             repo.create_file(