ci: Comment with code coverage summary (#41231)

After uploading the code coverage data, the server will reply with a
summary of the code coverage and a recommended state. Post that as a
comment to the PR.

.github/files/coverage-munger/upload-coverage.sh

@@ -3,9 +3,15 @@
 ## Environment used by this script:
 #
 # Required:
+# - API_TOKEN_GITHUB: GitHub API token.
+# - GITHUB_API_URL: GitHub API URL.
+# - GITHUB_TOKEN: GitHub API token.
+# - GITHUB_REPOSITORY: GitHub repo.
 # - GITHUB_SHA: Commit SHA.
+# - PR_HEAD: SHA for the PR head commit (versus GITHUB_SHA which is a merge commit)
 # - PR_ID: PR number or "trunk".
 # - SECRET: Shared secret.
+# - STATUS: Status of the coverage run.
 
 set -eo pipefail
 
@@ -95,3 +101,82 @@ done
 do_req "op=finish&token=$TOKEN"
 TOKEN=
 echo '::endgroup::'
+
+if [[ "$PR_ID" != "trunk" ]]; then
+	echo "::group::Setting GitHub status"
+	if jq -e '.covinfo' <<<"$JSON" &>/dev/null; then
+		JSON=$( jq '.covinfo' <<<"$JSON" )
+		if [[ "$STATUS" != 'success' ]]; then
+			JSON=$( jq '.state |= "pending" | .description |= "Waiting for tests to pass" | .msg |= "Cannot generate coverage summary while tests are failing. :zipper_mouth_face:\n\nPlease fix the tests, or re-run the Code coverage job if it was something being flaky."' <<<"$JSON" )
+		fi
+	else
+		JSON='{"state":"error","description":"No covinfo received from server","msg":"","footer":""}'
+	fi
+	jq . <<<"$JSON"
+	curl -v -L --fail \
+		--url "${GITHUB_API_URL}/repos/${GITHUB_REPOSITORY}/statuses/$( jq --arg V "$PR_HEAD" -nr '$V | @uri' )" \
+		--header "authorization: Bearer $API_TOKEN_GITHUB" \
+		--header 'content-type: application/json' \
+		--data "$( jq -c --arg PR "$PR_ID" '{
+			context: "Code coverage requirement",
+			state: .state,
+			target_url: "https://jetpackcodecoverage.atomicsites.blog/prs/\( $PR | @uri )/",
+			description: .description,
+		}' <<<"$JSON" )"
+	echo "::endgroup::"
+
+	# Find the last comment starting with "### Code Coverage Summary"
+	echo "::group::Looking for existing comment"
+	PAGE=1
+	while true; do
+		J=$( curl -v -L fail \
+			--url "${GITHUB_API_URL}/repos/${GITHUB_REPOSITORY}/issues/${ID}/comments?per_page=100&page=$PAGE" \
+			--header "authorization: Bearer $API_TOKEN_GITHUB"
+		)
+		CID=$( jq -r --arg CID "$CID" '[ { id: $CID }, ( .[] | select( .user.login == "github-actions[bot]" ) | select( .body | test( "^### Code Coverage Summary" ) ) ) ] | last | .id' <<<"$J" )
+		if jq -e 'length < 100' <<<"$J" &>/dev/null; then
+			break
+		fi
+		PAGE=$(( PAGE + 1 ))
+	done
+	echo "::endgroup::"
+	if [[ -n "$CID" ]]; then
+		echo "Existing comment ID=$CID"
+	else
+		echo "No existing comment found"
+	fi
+
+	if jq -e '.msg != ""' <<<"$JSON" &>/dev/null; then
+		if [[ -n "$CID" ]]; then
+			echo "::group::Updating comment"
+			curl -v -L --fail \
+				-X PATCH \
+				--url "${GITHUB_API_URL}/repos/${GITHUB_REPOSITORY}/issues/comments/${CID}" \
+				--header "authorization: Bearer $API_TOKEN_GITHUB" \
+				--header 'content-type: application/json' \
+				--data "$( jq -c '{
+					body: "### Code Coverage Summary\n\n\( .msg )\n\n\( .footer )",
+				}' <<<"$JSON" )"
+			echo "::endgroup::"
+		else
+			echo "::group::Creating comment"
+			curl -v -L --fail \
+				-X POST \
+				--url "${GITHUB_API_URL}/repos/${GITHUB_REPOSITORY}/issues/${ID}/comments" \
+				--header "authorization: Bearer $API_TOKEN_GITHUB" \
+				--header 'content-type: application/json' \
+				--data "$( jq -c '{
+					body: "### Code Coverage Summary\n\n\( .msg )\n\n\( .footer )",
+				}' <<<"$JSON" )"
+			echo "::endgroup::"
+		fi
+	elif [[ -n "$CID" ]]; then
+		# No message, delete existing comment.
+		echo "::group::Deleting comment"
+		curl -v -L --fail \
+			-X DELETE \
+			--url "${GITHUB_API_URL}/repos/${GITHUB_REPOSITORY}/issues/comments/${CID}" \
+			--header "authorization: Bearer $API_TOKEN_GITHUB"
+		echo "::endgroup::"
+	fi
+fi

.github/workflows/tests.yml

@@ -57,6 +57,7 @@ jobs:
     # Note matrix-job outputs are kind of weird. Last-to-run job that sets a non-empty value wins.
     outputs:
       did-coverage: ${{ ( steps.run-tests.conclusion != 'cancelled' && steps.process-coverage.conclusion == 'success' && steps.upload-artifacts.conclusion == 'success' ) && 'true' || '' }}
+      coverage-status: ${{ matrix.script == 'test-coverage' && steps.run-tests.conclusion || '' }}
 
     steps:
       - uses: actions/checkout@v4
@@ -305,6 +306,9 @@ jobs:
         env:
           PR_ID: ${{ github.event_name != 'pull_request' && 'trunk' || github.event.pull_request.number }}
           SECRET: ${{ secrets.CODECOV_SECRET }}
+          STATUS: ${{ needs.run-tests.outputs.coverage-status }}
+          PR_HEAD: ${{ github.event.pull_request.head.sha }}
+          API_TOKEN_GITHUB: ${{ secrets.GITHUB_TOKEN }}
         run: .github/files/coverage-munger/upload-coverage.sh
 
   storybook-test: