Ensure deactivate happens at most once, and yields same errors if called a second time (e.g. from forcefulShutdown)

Author: benjie

src/main.ts

@@ -590,35 +590,42 @@ export function _runTaskList(
 
   const promise = defer();
 
-  async function deactivate() {
-    if (workerPool._active) {
-      workerPool._active = false;
-      const errors: Error[] = [];
-      try {
-        await localQueue?.release();
-      } catch (rawE) {
-        const e = coerceError(rawE);
-        errors.push(e);
-        // Log but continue regardless
-        logger.error(`Releasing local queue failed: ${e}`, { error: rawE });
-      }
-      try {
-        // Note: this runs regardless of success of the above
-        await onDeactivate?.();
-      } catch (rawE) {
-        const e = coerceError(rawE);
-        errors.push(e);
-        // Log but continue regardless
-        logger.error(`onDeactivate raised an error: ${e}`, { error: rawE });
-      }
+  let deactivatePromise: Promise<void> | null = null;
 
-      if (errors.length > 0) {
-        throw new AggregateError(
-          errors,
-          "Errors occurred whilst deactivating queue",
-        );
-      }
+  function deactivate() {
+    if (!deactivatePromise) {
+      deactivatePromise = (async () => {
+        if (workerPool._active) {
+          workerPool._active = false;
+          const errors: Error[] = [];
+          try {
+            await localQueue?.release();
+          } catch (rawE) {
+            const e = coerceError(rawE);
+            errors.push(e);
+            // Log but continue regardless
+            logger.error(`Releasing local queue failed: ${e}`, { error: rawE });
+          }
+          try {
+            // Note: this runs regardless of success of the above
+            await onDeactivate?.();
+          } catch (rawE) {
+            const e = coerceError(rawE);
+            errors.push(e);
+            // Log but continue regardless
+            logger.error(`onDeactivate raised an error: ${e}`, { error: rawE });
+          }
+
+          if (errors.length > 0) {
+            throw new AggregateError(
+              errors,
+              "Errors occurred whilst deactivating queue",
+            );
+          }
+        }
+      })();
     }
+    return deactivatePromise;
   }
 
   let terminated = false;