PHAR prefix diff workflow

Author: ondrejmirtes

.github/workflows/phar-prefix-diff.yml

@@ -0,0 +1,92 @@
+# https://help.github.com/en/categories/automating-your-workflow-with-github-actions
+
+name: "PHAR Prefix Diff"
+
+on:
+  pull_request:
+    paths:
+      - 'compiler/**'
+      - '.github/workflows/phar-prefix-diff.yml'
+
+concurrency:
+  group: phar-prefix-diff-${{ github.head_ref || github.run_id }} # will be canceled on subsequent pushes in pull requests but not branches
+  cancel-in-progress: true
+
+jobs:
+  phar-prefix-diff:
+    name: "PHAR Prefix Diff"
+
+    runs-on: "ubuntu-latest"
+    timeout-minutes: 60
+
+    steps:
+      - name: Get base commit SHA
+        id: base
+        run: echo "base_sha=${{ github.event.pull_request.base.sha }}" >> "$GITHUB_OUTPUT"
+
+      - name: Find phar-file-checksum from base commit
+        id: find-artifact
+        uses: actions/github-script@v7
+        with:
+          script: |
+            const commitSha = `${{ steps.base.outputs.base_sha }}`
+            const artifactName = "phar-file-checksum"
+
+            // Get all workflow runs for this commit
+            const runs = await github.rest.actions.listWorkflowRunsForRepo({
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+              per_page: 20,
+              event: "push",
+              head_sha: commitSha
+            });
+
+            if (runs.data.workflow_runs.length === 0) {
+              core.setFailed(`No workflow runs found for commit ${commitSha}`);
+              return;
+            }
+
+
+            const workflowRuns = runs.data.workflow_runs;
+
+            if (workflowRuns.length === 0) {
+              core.setFailed(`No workflow runs found for commit ${commitSha}`);
+              return;
+            }
+
+            let found = false;
+            for (const run of workflowRuns) {
+              if (run.status !== "completed" || run.conclusion !== "success") {
+                continue;
+              }
+
+              if (run.name !== "Compile PHAR") {
+                continue;
+              }
+
+              const artifactsResp = await github.rest.actions.listWorkflowRunArtifacts({
+                owner: context.repo.owner,
+                repo: context.repo.repo,
+                run_id: run.id,
+              });
+
+              const artifact = artifactsResp.data.artifacts.find(a => a.name === artifactName);
+              if (artifact) {
+                core.setOutput("artifact_id", artifact.id);
+                core.setOutput("run_id", run.id);
+                found = true;
+                break;
+              }
+            }
+
+            if (!found) {
+              core.setFailed(`No artifact named '${expectedArtifactName}' found for commit ${commitSha}`);
+            }
+
+      - name: Download artifact by ID
+        uses: actions/download-artifact@v4
+        with:
+          artifact-ids: ${{ steps.find-artifact.outputs.artifact_id }}
+          run-id: ${{ steps.find-artifact.outputs.run_id }}
+          github-token: ${{ secrets.GITHUB_TOKEN }}
+          path: ./phar-file-checksum-old.phar