test_runner: avoid error when coverage line not found

PR-URL: #53000Fixes: #52775
Reviewed-By: Chemi Atlow <chemi@atlow.co.il>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Reviewed-By: Yagiz Nizipli <yagiz.nizipli@sentry.io>

Author: MoLow

lib/internal/test_runner/coverage.js

@@ -177,7 +177,7 @@ class TestCoverage {
 if(isBlockCoverage){
 ArrayPrototypePush(branchReports,{
 __proto__: null,
-line: range.lines[0].line,
+line: range.lines[0]?.line,
 count: range.count,
 });
 
@@ -197,7 +197,7 @@ class TestCoverage {
 __proto__: null,
 name: functions[j].functionName,
 count: maxCountPerFunction,
-line: range.lines[0].line,
+line: range.lines[0]?.line,
 });
 
 if(range.count!==0||range.ignoredLines===range.lines.length){

test/fixtures/test-runner/coverage-loader/hooks.mjs

@@ -0,0 +1,11 @@
+constsource=`
+ import { test } from 'node:test';
+ test('test', async () => {});
+`;
+
+exportasyncfunctionload(url,context,nextLoad){
+if(url.endsWith('virtual.js')){
+return{format: "module", source,shortCircuit: true};
+}
+returnnextLoad(url,context);
+}

test/fixtures/test-runner/coverage-loader/register-hooks.js

@@ -0,0 +1,4 @@
+const{ register }=require('node:module');
+const{ pathToFileURL }=require('node:url');
+
+register('./hooks.mjs',pathToFileURL(__filename));

test/fixtures/test-runner/coverage-loader/virtual.js

@@ -273,3 +273,33 @@ test('coverage with source maps', skipIfNoInspector, () => {
 assert(result.stdout.toString().includes(report));
 assert.strictEqual(result.status,1);
 });
+
+test('coverage with ESM hook - source irrelevant',skipIfNoInspector,()=>{
+letreport=[
+'# start of coverage report',
+'# ------------------------------------------------------------------',
+'# file | line % | branch % | funcs % | uncovered lines',
+'# ------------------------------------------------------------------',
+'# hooks.mjs | 100.00 | 100.00 | 100.00 | ',
+'# register-hooks.js | 100.00 | 100.00 | 100.00 | ',
+'# virtual.js | 100.00 | 100.00 | 100.00 | ',
+'# ------------------------------------------------------------------',
+'# all files | 100.00 | 100.00 | 100.00 |',
+'# ------------------------------------------------------------------',
+'# end of coverage report',
+].join('\n');
+
+if(common.isWindows){
+report=report.replaceAll('/','\\');
+}
+
+constfixture=fixtures.path('test-runner','coverage-loader');
+constargs=[
+'--import','./register-hooks.js','--test','--experimental-test-coverage','--test-reporter','tap','virtual.js',
+];
+constresult=spawnSync(process.execPath,args,{cwd: fixture});
+
+assert.strictEqual(result.stderr.toString(),'');
+assert(result.stdout.toString().includes(report));
+assert.strictEqual(result.status,0);
+});