Core: Exclude or grey internal frames from stack traces in TAP reporter

Internal frames are those from qunit.js, or Node.js runtime.

* Remove any internal frames from the top of the stack.
* Grey out later internal frames anywhere in the stack.

This change is applied to the TAP reporter, which the QUnit CLI uses
by default.

Closes #1789.

src/core/reporters/TapReporter.js

@@ -1,6 +1,7 @@
 import kleur from 'kleur';
 import { errorString } from '../utilities.js';
 import { console } from '../globals.js';
+import { annotateStacktrace } from '../stacktrace.js';
 
 const hasOwn = Object.prototype.hasOwnProperty;
 
@@ -276,7 +277,7 @@ export default class TapReporter {
     out += `\n  message: ${prettyYamlValue(errorString(error))}`;
     out += `\n  severity: ${prettyYamlValue('failed')}`;
     if (error && error.stack) {
-      out += `\n  stack: ${prettyYamlValue(error.stack + '\n')}`;
+      out += `\n  stack: ${prettyYamlValue(annotateStacktrace(error, kleur.grey) + '\n')}`;
     }
     out += '\n  ...';
     this.log(out);

src/core/stacktrace.js

@@ -59,6 +59,40 @@ function qunitFileName () {
 
 const fileName = qunitFileName();
 
+/**
+ * - For internal errors from QUnit itself, remove the first qunit.js frames.
+ * - For errors in Node.js, format any remaining qunit.js and node:internal
+ *   frames as internal (i.e. grey out).
+ */
+export function annotateStacktrace (e, formatInternal) {
+  if (!e || !e.stack) {
+    return String(e);
+  }
+  const frames = e.stack.split('\n');
+  const annotated = [];
+  if (e.toString().indexOf(frames[0]) !== -1) {
+    // In Firefox and Safari e.stack starts with frame 0, but in V8 (Chrome/Node.js),
+    // e.stack starts first stringified message. Preserve this separately,
+    // so that, below, we can distinguish between internal frames on top
+    // (to remove) vs later internal frames (to format differently).
+    annotated.push(frames.shift());
+  }
+  let initialInternal = true;
+  for (let i = 0; i < frames.length; i++) {
+    const frame = frames[i];
+    const isInternal = (frame.indexOf(fileName) !== -1 || frame.indexOf('node:internal/') !== -1);
+    if (!isInternal) {
+      initialInternal = false;
+    }
+    // Remove initial internal frames entirely.
+    if (!initialInternal) {
+      annotated.push(isInternal ? formatInternal(frame) : frame);
+    }
+  }
+
+  return annotated.join('\n');
+}
+
 export function extractStacktrace (e, offset) {
   offset = offset === undefined ? 4 : offset;
 

test/cli/fixtures/async-module-error-promise.tap.txt

@@ -9,7 +9,6 @@ not ok 1 global failure
   severity: failed
   stack: |
     TypeError: QUnit.module() callback must not be async. For async module setup, use hooks. https://qunitjs.com/api/QUnit/module/#hooks
-        at qunit.js
         at /qunit/test/cli/fixtures/async-module-error-promise.js:1:7
         at internal
   ...

test/cli/fixtures/async-module-error-thenable.tap.txt

@@ -9,7 +9,6 @@ not ok 1 global failure
   severity: failed
   stack: |
     TypeError: QUnit.module() callback must not be async. For async module setup, use hooks. https://qunitjs.com/api/QUnit/module/#hooks
-        at qunit.js
         at /qunit/test/cli/fixtures/async-module-error-thenable.js:1:7
         at internal
   ...

test/cli/fixtures/async-module-error.tap.txt

@@ -9,7 +9,6 @@ not ok 1 global failure
   severity: failed
   stack: |
     TypeError: QUnit.module() callback must not be async. For async module setup, use hooks. https://qunitjs.com/api/QUnit/module/#hooks
-        at qunit.js
         at /qunit/test/cli/fixtures/async-module-error.js:2:7
         at internal
   ...