test_runner: execute before hook on test

Execute the before hook for Test as well, and execute it on root before
executing any tests.
Fixes: #47518
PR-URL: #47586
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Reviewed-By: Moshe Atlow <moshe@atlow.co.il>

Author: atlowChemi

doc/api/test.md

@@ -1429,12 +1429,36 @@ Emitted when a test starts.
 
 <!-- YAML
 added: v18.0.0
+changes:
+ - version: REPLACEME
+ pr-url: https://github.com/nodejs/node/pull/47586
+ description: The `before` function was added to TestContext.
 -->
 
 An instance of `TestContext` is passed to each test function in order to
 interact with the test runner. However, the `TestContext` constructor is not
 exposed as part of the API.
 
+### `context.before([fn][, options])`
+
+<!-- YAML
+added: REPLACEME
+-->
+
+*`fn` {Function|AsyncFunction} The hook function. The first argument
+ to this function is a [`TestContext`][] object. If the hook uses callbacks,
+ the callback function is passed as the second argument. **Default:** A no-op
+ function.
+*`options` {Object} Configuration options for the hook. The following
+ properties are supported:
+*`signal` {AbortSignal} Allows aborting an in-progress hook.
+*`timeout` {number} A number of milliseconds the hook will fail after.
+ If unspecified, subtests inherit this value from their parent.
+**Default:**`Infinity`.
+
+This function is used to create a hook running before
+subtest of the current test.
+
 ### `context.beforeEach([fn][, options])`
 
 <!-- YAML

lib/internal/test_runner/test.js

@@ -127,6 +127,10 @@ class TestContext {
 returnsubtest.start();
 }
 
+before(fn,options){
+this.#test.createHook('before',fn,options);
+}
+
 after(fn,options){
 this.#test.createHook('after',fn,options);
 }
@@ -414,6 +418,9 @@ class Test extends AsyncResource {
 validateOneOf(name,'hook name',kHookNames);
 // eslint-disable-next-line no-use-before-define
 consthook=newTestHook(fn,options);
+if(name==='before'){
+hook.run=runOnce(hook.run);
+}
 ArrayPrototypePush(this.hooks[name],hook);
 returnhook;
 }
@@ -525,6 +532,9 @@ class Test extends AsyncResource {
 if(this.parent?.hooks.beforeEach.length>0){
 awaitthis.parent.runHook('beforeEach',{ args, ctx });
 }
+if(this.parent?.hooks.before.length>0){
+awaitthis.parent.runHook('before',this.parent.getRunArgs());
+}
 conststopPromise=stopTest(this.timeout,this.signal);
 construnArgs=ArrayPrototypeSlice(args);
 ArrayPrototypeUnshift(runArgs,this.fn,ctx);
@@ -561,7 +571,7 @@ class Test extends AsyncResource {
 this.pass();
 }catch(err){
 try{awaitafter();}catch{/* Ignore error. */}
-try{awaitafterEach();}catch{/* test is already failing, let's the error */}
+try{awaitafterEach();}catch{/* test is already failing, let's ignore the error */}
 if(isTestFailureError(err)){
 if(err.failureType===kTestTimeoutFailure){
 this.#cancel(err);
@@ -793,7 +803,7 @@ class Suite extends Test {
 
 this.pass();
 }catch(err){
-try{awaitafterEach();}catch{/* test is already failing, let's the error */}
+try{awaitafterEach();}catch{/* test is already failing, let's ignore the error */}
 if(isTestFailureError(err)){
 this.fail(err);
 }else{

test/fixtures/test-runner/output/hooks.js

@@ -4,6 +4,8 @@ const common = require('../../../common');
 constassert=require('assert');
 const{ test, describe, it, before, after, beforeEach, afterEach }=require('node:test');
 
+before((t)=>t.diagnostic('before 1 called'));
+
 describe('describe hooks',()=>{
 consttestArr=[];
 before(function(){
@@ -91,6 +93,7 @@ describe('afterEach throws and test fails', () => {
 test('test hooks',async(t)=>{
 consttestArr=[];
 
+t.before((t)=>testArr.push('before '+t.name));
 t.after(common.mustCall((t)=>testArr.push('after '+t.name)));
 t.beforeEach((t)=>testArr.push('beforeEach '+t.name));
 t.afterEach((t)=>testArr.push('afterEach '+t.name));
@@ -105,7 +108,7 @@ test('test hooks', async (t) => {
 });
 
 assert.deepStrictEqual(testArr,[
-'beforeEach 1','1','afterEach 1',
+'beforeEach 1','before test hooks','1','afterEach 1',
 'beforeEach 2','2','afterEach 2',
 'beforeEach nested',
 'nested beforeEach nested 1','nested1','nested afterEach nested 1',
@@ -114,6 +117,13 @@ test('test hooks', async (t) => {
 ]);
 });
 
+test('t.before throws',async(t)=>{
+t.after(common.mustCall());
+t.before(()=>{thrownewError('before');});
+awaitt.test('1',()=>{});
+awaitt.test('2',()=>{});
+});
+
 test('t.beforeEach throws',async(t)=>{
 t.after(common.mustCall());
 t.beforeEach(()=>{thrownewError('beforeEach');});
@@ -149,3 +159,5 @@ test('t.after() is called if test body throws', (t) => {
 });
 thrownewError('bye');
 });
+
+before((t)=>t.diagnostic('before 2 called'));

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

@@ -67,6 +67,7 @@ not ok 2 - before throws
  *
  *
  *
+ *
  ...
 # Subtest: after throws
  # Subtest: 1
@@ -307,6 +308,53 @@ ok 8 - test hooks
  ---
  duration_ms: *
  ...
+# Subtest: t.before throws
+ # Subtest: 1
+ not ok 1 - 1
+ ---
+ duration_ms: *
+ failureType: 'hookFailed'
+ error: 'failed running before hook'
+ code: 'ERR_TEST_FAILURE'
+ stack: |-
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ ...
+ # Subtest: 2
+ not ok 2 - 2
+ ---
+ duration_ms: *
+ failureType: 'hookFailed'
+ error: 'failed running before hook'
+ code: 'ERR_TEST_FAILURE'
+ stack: |-
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ ...
+ 1..2
+not ok 9 - t.before throws
+ ---
+ duration_ms: *
+ failureType: 'subtestsFailed'
+ error: '2 subtests failed'
+ code: 'ERR_TEST_FAILURE'
+ ...
 # Subtest: t.beforeEach throws
  # Subtest: 1
  not ok 1 - 1
@@ -347,7 +395,7 @@ ok 8 - test hooks
  *
  ...
  1..2
-not ok 9 - t.beforeEach throws
+not ok 10 - t.beforeEach throws
  ---
  duration_ms: *
  failureType: 'subtestsFailed'
@@ -394,7 +442,7 @@ not ok 9 - t.beforeEach throws
  *
  ...
  1..2
-not ok 10 - t.afterEach throws
+not ok 11 - t.afterEach throws
  ---
  duration_ms: *
  failureType: 'subtestsFailed'
@@ -419,15 +467,14 @@ not ok 10 - t.afterEach throws
  *
  *
  *
- *
  ...
  # Subtest: 2
  ok 2 - 2
  ---
  duration_ms: *
  ...
  1..2
-not ok 11 - afterEach when test fails
+not ok 12 - afterEach when test fails
  ---
  duration_ms: *
  failureType: 'subtestsFailed'
@@ -452,7 +499,6 @@ not ok 11 - afterEach when test fails
  *
  *
  *
- *
  ...
  # Subtest: 2
  not ok 2 - 2
@@ -474,15 +520,15 @@ not ok 11 - afterEach when test fails
  *
  ...
  1..2
-not ok 12 - afterEach throws and test fails
+not ok 13 - afterEach throws and test fails
  ---
  duration_ms: *
  failureType: 'subtestsFailed'
  error: '2 subtests failed'
  code: 'ERR_TEST_FAILURE'
  ...
 # Subtest: t.after() is called if test body throws
-not ok 13 - t.after() is called if test body throws
+not ok 14 - t.after() is called if test body throws
  ---
  duration_ms: *
  failureType: 'testCodeFailure'
@@ -493,16 +539,15 @@ not ok 13 - t.after() is called if test body throws
  *
  *
  *
- *
- *
- *
  ...
 # - after() called
-1..13
-# tests 35
+1..14
+# before 1 called
+# before 2 called
+# tests 38
 # suites 8
 # pass 14
-# fail 19
+# fail 22
 # cancelled 2
 # skipped 0
 # todo 0