Unconditionally report unwritten diagnostics at the end of the init Action

src/diagnostics.ts

@@ -149,6 +149,21 @@ function writeDiagnostic(
   }
 }
 
+/** Report if there are unwritten diagnostics and write them to the log. */
+export function logUnwrittenDiagnostics() {
+  const logger = getActionsLogger();
+  const num = unwrittenDiagnostics.length;
+  if (num > 0) {
+    logger.warning(
+      `${num} diagnostic(s) could not be written to the database and will not appear on the Tool Status Page.`,
+    );
+
+    for (const unwritten of unwrittenDiagnostics) {
+      logger.debug(JSON.stringify(unwritten.diagnostic));
+    }
+  }
+}
+
 /** Writes all unwritten diagnostics to disk. */
 export function flushDiagnostics(config: Config) {
   const logger = getActionsLogger();

src/init-action.ts

@@ -16,7 +16,12 @@ import {
 import { getGitHubVersion } from "./api-client";
 import { CodeQL } from "./codeql";
 import * as configUtils from "./config-utils";
-import { addDiagnostic, flushDiagnostics, makeDiagnostic } from "./diagnostics";
+import {
+  addDiagnostic,
+  flushDiagnostics,
+  logUnwrittenDiagnostics,
+  makeDiagnostic,
+} from "./diagnostics";
 import { EnvVar } from "./environment";
 import { Feature, Features } from "./feature-flags";
 import { checkInstallPython311, initCodeQL, initConfig, runInit } from "./init";
@@ -541,6 +546,8 @@ async function run() {
       error,
     );
     return;
+  } finally {
+    logUnwrittenDiagnostics();
   }
   await sendCompletedStatusReport(
     startedAt,