test_runner: run top level tests in a microtask

This commit updates the test harness to prevent top level
tests from executing immediately. This allows certain config
data, such as filtering options, to be discovered before running
the tests.
PR-URL: #52092
Reviewed-By: Moshe Atlow <moshe@atlow.co.il>
Reviewed-By: Chemi Atlow <chemi@atlow.co.il>

Author: cjihrig

lib/internal/test_runner/harness.js

@@ -26,6 +26,7 @@ const {
  setupTestReporters,
  shouldColorizeTestFiles,
 }=require('internal/test_runner/utils');
+const{ queueMicrotask }=require('internal/process/task_queues');
 const{bigint: hrtime}=process.hrtime;
 
 consttestResources=newSafeMap();
@@ -189,6 +190,7 @@ function setup(root) {
 
 root.harness={
 __proto__: null,
+allowTestsToRun: false,
 bootstrapComplete: false,
 watching: false,
 coverage: FunctionPrototypeBind(collectCoverage,null,root,coverage),
@@ -232,7 +234,16 @@ function getGlobalRoot() {
 
 asyncfunctionstartSubtest(subtest){
 awaitreportersSetup;
-getGlobalRoot().harness.bootstrapComplete=true;
+
+constroot=getGlobalRoot();
+if(!root.harness.bootstrapComplete){
+root.harness.bootstrapComplete=true;
+queueMicrotask(()=>{
+root.harness.allowTestsToRun=true;
+root.processPendingSubtests();
+});
+}
+
 awaitsubtest.start();
 }
 

lib/internal/test_runner/runner.js

@@ -590,6 +590,7 @@ function run(options) {
 }
 construnFiles=()=>{
 root.harness.bootstrapComplete=true;
+root.harness.allowTestsToRun=true;
 returnSafePromiseAllSettledReturnVoid(testFiles,(path)=>{
 constsubtest=runTestFile(path,filesWatcher,opts);
 filesWatcher?.runningSubtests.set(path,subtest);

lib/internal/test_runner/test.js

@@ -584,7 +584,7 @@ class Test extends AsyncResource {
 // it. Otherwise, return a Promise to the caller and mark the test as
 // pending for later execution.
 this.reporter.enqueue(this.nesting,this.loc,this.name);
-if(!this.parent.hasConcurrency()){
+if(!this.root.harness.allowTestsToRun||!this.parent.hasConcurrency()){
 constdeferred=createDeferredPromise();
 
 deferred.test=this;

test/fixtures/test-runner/output/source_mapped_locations.snapshot

@@ -21,6 +21,9 @@ not ok 1 - fails
  *
  *
  *
+ *
+ *
+ *
  ...
 1..1
 # tests 1