test_runner: added tests for test shorthands

Added test to check that the return type of the `todo`, `only` and `skip` shorthands
are consistent with the return type of `test`.

test/parallel/test-runner-typechecking.js

@@ -0,0 +1,34 @@
+'use strict';
+const common = require('../common');
+
+// Return type of shorthands should be consistent
+// with the return type of test
+
+const assert = require('assert');
+const test = require('node:test');
+const { isPromise } = require('util/types');
+
+const testOnly = test({ only: true });
+const testTodo = test({ todo: true });
+const testSkip = test({ skip: true });
+const testOnlyShorthand = test.only();
+const testTodoShorthand = test.todo();
+const testSkipShorthand = test.skip();
+
+// return Promise
+assert(isPromise(testOnly));
+assert(isPromise(testTodo));
+assert(isPromise(testSkip));
+assert(isPromise(testOnlyShorthand));
+assert(isPromise(testTodoShorthand));
+assert(isPromise(testSkipShorthand));
+
+// resolve to undefined
+(async () => {
+  assert.strictEqual(await testOnly, undefined);
+  assert.strictEqual(await testTodo, undefined);
+  assert.strictEqual(await testSkip, undefined);
+  assert.strictEqual(await testOnlyShorthand, undefined);
+  assert.strictEqual(await testTodoShorthand, undefined);
+  assert.strictEqual(await testSkipShorthand, undefined);
+})().then(common.mustCall());