test: improve coverage on worker threads

PR-URL: #36910
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>

test/parallel/test-worker-unsupported-things.js

@@ -24,6 +24,14 @@ if (!process.env.HAS_STARTED_WORKER) {
     assert.strictEqual(process.debugPort, before);
   }
 
+  {
+    const mask = 0o600;
+    assert.throws(() => { process.umask(mask); }, {
+      code: 'ERR_WORKER_UNSUPPORTED_OPERATION',
+      message: 'Setting process.umask() is not supported in workers'
+    });
+  }
+
   const stubs = ['abort', 'chdir', 'send', 'disconnect'];
 
   if (!common.isWindows) {
@@ -35,13 +43,19 @@ if (!process.env.HAS_STARTED_WORKER) {
     assert.strictEqual(process[fn].disabled, true);
     assert.throws(() => {
       process[fn]();
-    }, { code: 'ERR_WORKER_UNSUPPORTED_OPERATION' });
+    }, {
+      code: 'ERR_WORKER_UNSUPPORTED_OPERATION',
+      message: `process.${fn}() is not supported in workers`
+    });
   });
 
   ['channel', 'connected'].forEach((fn) => {
     assert.throws(() => {
       process[fn]; // eslint-disable-line no-unused-expressions
-    }, { code: 'ERR_WORKER_UNSUPPORTED_OPERATION' });
+    }, {
+      code: 'ERR_WORKER_UNSUPPORTED_OPERATION',
+      message: `process.${fn} is not supported in workers`
+    });
   });
 
   assert.strictEqual('_startProfilerIdleNotifier' in process, false);