From 06ab0bb19e84bc9f733570b3d746c52cffbf1a42 Mon Sep 17 00:00:00 2001
From: Moshe Atlow <moshe@atlow.co.il>
Date: Fri, 17 May 2024 11:46:52 +0300
Subject: [PATCH] test_runner: avoid error when coverage line not found

PR-URL: https://github.com/nodejs/node/pull/53000
Fixes: https://github.com/nodejs/node/issues/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>
---
 lib/internal/test_runner/coverage.js          |  4 +--
 .../test-runner/coverage-loader/hooks.mjs     | 11 +++++++
 .../coverage-loader/register-hooks.js         |  4 +++
 .../test-runner/coverage-loader/virtual.js    |  0
 test/parallel/test-runner-coverage.js         | 30 +++++++++++++++++++
 5 files changed, 47 insertions(+), 2 deletions(-)
 create mode 100644 test/fixtures/test-runner/coverage-loader/hooks.mjs
 create mode 100644 test/fixtures/test-runner/coverage-loader/register-hooks.js
 create mode 100644 test/fixtures/test-runner/coverage-loader/virtual.js

diff --git a/lib/internal/test_runner/coverage.js b/lib/internal/test_runner/coverage.js
index 50f9f94172ef4d..427a467ba0072b 100644
--- a/lib/internal/test_runner/coverage.js
+++ b/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) {
diff --git a/test/fixtures/test-runner/coverage-loader/hooks.mjs b/test/fixtures/test-runner/coverage-loader/hooks.mjs
new file mode 100644
index 00000000000000..1aa04d0b45589d
--- /dev/null
+++ b/test/fixtures/test-runner/coverage-loader/hooks.mjs
@@ -0,0 +1,11 @@
+const source = `
+  import { test } from 'node:test';
+  test('test', async () => {});
+`;
+
+export async function load(url, context, nextLoad) {
+  if (url.endsWith('virtual.js')) {
+    return { format: "module", source, shortCircuit: true };
+  }
+  return nextLoad(url, context);
+}
diff --git a/test/fixtures/test-runner/coverage-loader/register-hooks.js b/test/fixtures/test-runner/coverage-loader/register-hooks.js
new file mode 100644
index 00000000000000..cbbac61264112b
--- /dev/null
+++ b/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));
diff --git a/test/fixtures/test-runner/coverage-loader/virtual.js b/test/fixtures/test-runner/coverage-loader/virtual.js
new file mode 100644
index 00000000000000..e69de29bb2d1d6
diff --git a/test/parallel/test-runner-coverage.js b/test/parallel/test-runner-coverage.js
index c059e0ed8df936..05057bf40838e8 100644
--- a/test/parallel/test-runner-coverage.js
+++ b/test/parallel/test-runner-coverage.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, () => {
+  let report = [
+    '# 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('/', '\\');
+  }
+
+  const fixture = fixtures.path('test-runner', 'coverage-loader');
+  const args = [
+    '--import', './register-hooks.js', '--test', '--experimental-test-coverage', '--test-reporter', 'tap', 'virtual.js',
+  ];
+  const result = spawnSync(process.execPath, args, { cwd: fixture });
+
+  assert.strictEqual(result.stderr.toString(), '');
+  assert(result.stdout.toString().includes(report));
+  assert.strictEqual(result.status, 0);
+});