test_runner: reset count on watch mode

Author: MoLow

lib/internal/test_runner/runner.js

@@ -296,7 +296,11 @@ function runTestFile(path, root, inspectPort, filesWatcher) {
       throw err;
     }
   });
-  return subtest.start();
+  const promise = subtest.start();
+  if (filesWatcher) {
+    return PromisePrototypeThen(promise, () => root.removeSubtest(subtest));
+  }
+  return promise;
 }
 
 function watchFiles(testFiles, root, inspectPort) {

lib/internal/test_runner/test.js

@@ -1,11 +1,13 @@
 'use strict';
 const {
+  ArrayPrototypeIndexOf,
   ArrayPrototypeMap,
   ArrayPrototypePush,
   ArrayPrototypeReduce,
   ArrayPrototypeShift,
   ArrayPrototypeSlice,
   ArrayPrototypeSome,
+  ArrayPrototypeSplice,
   ArrayPrototypeUnshift,
   FunctionPrototype,
   MathMax,
@@ -344,6 +346,14 @@ class Test extends AsyncResource {
     }
   }
 
+  removeSubtest(subtest) {
+    const index = ArrayPrototypeIndexOf(this.subtests, subtest);
+    if (index !== -1) {
+      ArrayPrototypeSplice(this.subtests, index, 1);
+      this.waitingOn--;
+    }
+  }
+
   createSubtest(Factory, name, options, fn, overrides) {
     if (typeof name === 'function') {
       fn = name;

test/parallel/test-runner-watch-mode.mjs

@@ -11,10 +11,14 @@ async function testWatch({ files, fileToUpdate }) {
   const ran2 = util.createDeferredPromise();
   const child = spawn(process.execPath, ['--watch', '--test', '--no-warnings', ...files], { encoding: 'utf8' });
   let stdout = '';
+  let count = 0;
   child.stdout.on('data', (data) => {
     stdout += data.toString();
-    if (/ok 2/.test(stdout)) ran1.resolve();
-    if (/ok 3/.test(stdout)) ran2.resolve();
+    if (/ok 1 - /.test(stdout)) {
+      count++;
+    }
+    if (count === 2) ran1.resolve();
+    if (count === 3) ran2.resolve();
   });
 
   await ran1.promise;