Add e2e test

Author: mbg

.github/workflows/__diagnostics-without-db.yml

@@ -0,0 +1,27 @@
+name: "Diagnostic export without database"
+description: "Tests that temporary diagnostics are correctly included in the failed SARIF."
+versions:
+  # Overriden by the FF below.
+  - linked
+installNode: true
+steps:
+  # We deliberately need to make this step fail before the database is initialised, but after
+  # some diagnostic has been produced. The simplest way to do that right now is to force the
+  # use of a nightly release and then fail because we are attempting to analyse Swift on
+  # a non-macOS runner.
+  - name: Initialise failing analysis
+    id: init
+    uses: ./../action/init
+    continue-on-error: true
+    env:
+      CODEQL_ACTION_FORCE_NIGHTLY: true
+    with:
+      languages: swift
+      tools: ${{ steps.prepare-test.outputs.tools-url }}
+
+  - name: Check diagnostics appear on disk
+    env:
+      SARIF_PATH: "${{ runner.temp }}/codeql-action-temp-diagnostics/"
+    run: |
+      cd ../action
+      npx tsx ./pr-checks/diagnostics-without-db.ts

pr-checks/checks/diagnostics-without-db.yml

@@ -0,0 +1,48 @@
+import * as fs from "fs";
+import * as path from "path";
+
+import * as core from "@actions/core";
+
+import type * as diagnostics from "../src/diagnostics";
+
+const DIAGNOSTIC_ID = "codeql-action/forced-nightly-cli";
+const sarifDirectory = process.env["SARIF_PATH"];
+
+if (sarifDirectory === undefined) {
+  throw new Error("SARIF_PATH is undefined.");
+}
+
+const paths = fs
+  .readdirSync(sarifDirectory, {
+    recursive: true,
+    encoding: "utf-8",
+  })
+  .filter((p) => p.endsWith(".json"));
+
+core.info(`Found ${paths.length} paths in '${sarifDirectory}'.`);
+core.info(`Searching for a diagnostic with id '${DIAGNOSTIC_ID}'...`);
+
+let found = false;
+for (const diagnosticPath of paths) {
+  if (path.extname(diagnosticPath) !== ".json") {
+    core.info(`Skipping ${diagnosticPath}.`);
+    continue;
+  }
+  core.info(`Found ${diagnosticPath}.`);
+
+  const contents = JSON.parse(
+    fs.readFileSync(path.resolve(sarifDirectory, diagnosticPath), "utf-8"),
+  ) as diagnostics.DiagnosticMessage;
+
+  if (contents.source.id === DIAGNOSTIC_ID) {
+    core.info(
+      `Found '${DIAGNOSTIC_ID}' in '${diagnosticPath}'. Skipping remaining files.`,
+    );
+    found = true;
+    break;
+  }
+}
+
+if (!found) {
+  throw new Error(`Didn't find '${DIAGNOSTIC_ID}' diagnostic.`);
+}