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Test262: ECMAScript Test Suite (ECMA TR/104)

Test262 is the implementation conformance test suite for the latest drafts (or most recent published edition) of the following Ecma specifications:

Test262 itself is described in ECMA TR/104 and is included in ECMA-414 (pdf).

Goals & State of Test262

The goal of Test262 is to provide test material that covers every observable behavior specified in the ECMA-414 Standards Suite. Development of Test262 is an on-going process. As of May 2025, Test262 consisted of over 50,000 individual test files covering the majority of the pseudo-code algorithms and grammar productions defined in the ECMA-414 Standards Suite. Each of these files contains one or more distinct test cases. This marks the most comprehensive ECMAScript test suite to date. While test coverage is broad, TC39 does not consider coverage to be complete and as with any software project there exists the possibility of omissions and errors. This project welcomes any contributions to Test262 that help make test coverage of existing features more comprehensive.

ECMAScript feature proposals

As defined in the TC39 Process, Stage 4 Entrance Criteria requires tests for new feature proposals to advance. Tests may be written by proposal champions, implementers, or any interested community member.

A proposal champion is someone that worked on the feature proposal and specification directly.

An implementer is someone that works on implementing the proposal into a JavaScript engine, parser, runtime or embedding.

A community member is you, and we welcome you to contribute! If you're having trouble getting started, or even just want to ask a question, feel free to open an issue.

Contributing to Test262

Guidance for contributing to Test262 can be found in CONTRIBUTING.md.

Authors of contributions from non-Ecma member organizations must sign the Test262 CLA

Running Test262

Guidance for running Test262 and explanations of how a test file must be interpreted by a test runner is in INTERPRETING

Rationale

This project offers an explanation for many of its design decisions and maintenance practices--see rationale.md.

Test262 Runners

Volunteer-maintained projects that may be used to execute Test262 in various ECMAScript hosts:

How To Read CI Results

Test262 runs CI tests against every PR and commit. The only tests that are required to pass are visibly flagged as REQUIRED. The CI test results that are attributed to specific runs against specific engines should not be perceived as meaningful to anyone but the person that is reviewing the test material contained within the contributed changeset. These tests are almost always expected to fail, especially in the case of tests for new features. They may be helpful in determining whether or not a regression occurred, but that can only be determined by an actual human reviewing the results and comparing those outcomes to the expected outcomes of the tests.

Where did website/ go?

It's been removed. If you need to access the code that contained in that directory, you can find it here.

About

Official ECMAScript Conformance Test Suite

Resources

Readme
License

Code of conduct

Code of conduct

Contributing

Contributing
Activity

Stars

0 stars

Watchers

0 watching

Forks

0 forks
Report repository

Releases

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})();
(function(){
try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '

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Test262: ECMAScript Test Suite (ECMA TR/104)
Test262 is the implementation conformance test suite for the latest drafts (or most recent published edition) of the following Ecma specifications:
Test262 itself is described in ECMA TR/104 and is included in ECMA-414 (pdf).
Goals & State of Test262
The goal of Test262 is to provide test material that covers every observable behavior specified in the ECMA-414 Standards Suite. Development of Test262 is an on-going process. As of May 2025, Test262 consisted of over 50,000 individual test files covering the majority of the pseudo-code algorithms and grammar productions defined in the ECMA-414 Standards Suite. Each of these files contains one or more distinct test cases. This marks the most comprehensive ECMAScript test suite to date. While test coverage is broad, TC39 does not consider coverage to be complete and as with any software project there exists the possibility of omissions and errors. This project welcomes any contributions to Test262 that help make test coverage of existing features more comprehensive.
ECMAScript feature proposals
As defined in the TC39 Process, Stage 4 Entrance Criteria requires tests for new feature proposals to advance. Tests may be written by proposal champions, implementers, or any interested community member.
A proposal champion is someone that worked on the feature proposal and specification directly.
An implementer is someone that works on implementing the proposal into a JavaScript engine, parser, runtime or embedding.
A community member is you, and we welcome you to contribute! If you're having trouble getting started, or even just want to ask a question, feel free to open an issue.
Contributing to Test262
Guidance for contributing to Test262 can be found in CONTRIBUTING.md.
Authors of contributions from non-Ecma member organizations must sign the Test262 CLA
Running Test262
Guidance for running Test262 and explanations of how a test file must be interpreted by a test runner is in INTERPRETING
Rationale
This project offers an explanation for many of its design decisions and maintenance practices--see rationale.md.
Test262 Runners
Volunteer-maintained projects that may be used to execute Test262 in various ECMAScript hosts:
How To Read CI Results
Test262 runs CI tests against every PR and commit. The only tests that are required to pass are visibly flagged as REQUIRED. The CI test results that are attributed to specific runs against specific engines should not be perceived as meaningful to anyone but the person that is reviewing the test material contained within the contributed changeset. These tests are almost always expected to fail, especially in the case of tests for new features. They may be helpful in determining whether or not a regression occurred, but that can only be determined by an actual human reviewing the results and comparing those outcomes to the expected outcomes of the tests.
Where did website/ go?
It's been removed. If you need to access the code that contained in that directory, you can find it here.
About
Official ECMAScript Conformance Test Suite
Resources
Readme
License
Code of conduct
Code of conduct
Contributing
Contributing
Activity
Stars
0 stars
Watchers
0 watching
Forks
0 forks
Report repository
Releases
Packages
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, 'i');
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var style = document.createElement('style');
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})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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Test262: ECMAScript Test Suite (ECMA TR/104)
Test262 is the implementation conformance test suite for the latest drafts (or most recent published edition) of the following Ecma specifications:
Test262 itself is described in ECMA TR/104 and is included in ECMA-414 (pdf).
Goals & State of Test262
The goal of Test262 is to provide test material that covers every observable behavior specified in the ECMA-414 Standards Suite. Development of Test262 is an on-going process. As of May 2025, Test262 consisted of over 50,000 individual test files covering the majority of the pseudo-code algorithms and grammar productions defined in the ECMA-414 Standards Suite. Each of these files contains one or more distinct test cases. This marks the most comprehensive ECMAScript test suite to date. While test coverage is broad, TC39 does not consider coverage to be complete and as with any software project there exists the possibility of omissions and errors. This project welcomes any contributions to Test262 that help make test coverage of existing features more comprehensive.
ECMAScript feature proposals
As defined in the TC39 Process, Stage 4 Entrance Criteria requires tests for new feature proposals to advance. Tests may be written by proposal champions, implementers, or any interested community member.
A proposal champion is someone that worked on the feature proposal and specification directly.
An implementer is someone that works on implementing the proposal into a JavaScript engine, parser, runtime or embedding.
A community member is you, and we welcome you to contribute! If you're having trouble getting started, or even just want to ask a question, feel free to open an issue.
Contributing to Test262
Guidance for contributing to Test262 can be found in CONTRIBUTING.md.
Authors of contributions from non-Ecma member organizations must sign the Test262 CLA
Running Test262
Guidance for running Test262 and explanations of how a test file must be interpreted by a test runner is in INTERPRETING
Rationale
This project offers an explanation for many of its design decisions and maintenance practices--see rationale.md.
Test262 Runners
Volunteer-maintained projects that may be used to execute Test262 in various ECMAScript hosts:
How To Read CI Results
Test262 runs CI tests against every PR and commit. The only tests that are required to pass are visibly flagged as REQUIRED. The CI test results that are attributed to specific runs against specific engines should not be perceived as meaningful to anyone but the person that is reviewing the test material contained within the contributed changeset. These tests are almost always expected to fail, especially in the case of tests for new features. They may be helpful in determining whether or not a regression occurred, but that can only be determined by an actual human reviewing the results and comparing those outcomes to the expected outcomes of the tests.
Where did website/ go?
It's been removed. If you need to access the code that contained in that directory, you can find it here.
About
Official ECMAScript Conformance Test Suite
Resources
Readme
License
Code of conduct
Code of conduct
Contributing
Contributing
Activity
Stars
0 stars
Watchers
0 watching
Forks
0 forks
Report repository
Releases
Packages
Contributors
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, 'i');
if (__m === '*' || __re.test(location.href)) {
// Highlight search terms from Google/DuckDuckGo/Bing referrer
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var ref = document.referrer;
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highlight(document.body);
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observer.observe(document.body, { childList: true, subtree: true });
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} catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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Test262: ECMAScript Test Suite (ECMA TR/104)
Test262 is the implementation conformance test suite for the latest drafts (or most recent published edition) of the following Ecma specifications:
Test262 itself is described in ECMA TR/104 and is included in ECMA-414 (pdf).
Goals & State of Test262
The goal of Test262 is to provide test material that covers every observable behavior specified in the ECMA-414 Standards Suite. Development of Test262 is an on-going process. As of May 2025, Test262 consisted of over 50,000 individual test files covering the majority of the pseudo-code algorithms and grammar productions defined in the ECMA-414 Standards Suite. Each of these files contains one or more distinct test cases. This marks the most comprehensive ECMAScript test suite to date. While test coverage is broad, TC39 does not consider coverage to be complete and as with any software project there exists the possibility of omissions and errors. This project welcomes any contributions to Test262 that help make test coverage of existing features more comprehensive.
ECMAScript feature proposals
As defined in the TC39 Process, Stage 4 Entrance Criteria requires tests for new feature proposals to advance. Tests may be written by proposal champions, implementers, or any interested community member.
A proposal champion is someone that worked on the feature proposal and specification directly.
An implementer is someone that works on implementing the proposal into a JavaScript engine, parser, runtime or embedding.
A community member is you, and we welcome you to contribute! If you're having trouble getting started, or even just want to ask a question, feel free to open an issue.
Contributing to Test262
Guidance for contributing to Test262 can be found in CONTRIBUTING.md.
Authors of contributions from non-Ecma member organizations must sign the Test262 CLA
Running Test262
Guidance for running Test262 and explanations of how a test file must be interpreted by a test runner is in INTERPRETING
Rationale
This project offers an explanation for many of its design decisions and maintenance practices--see rationale.md.
Test262 Runners
Volunteer-maintained projects that may be used to execute Test262 in various ECMAScript hosts:
How To Read CI Results
Test262 runs CI tests against every PR and commit. The only tests that are required to pass are visibly flagged as REQUIRED. The CI test results that are attributed to specific runs against specific engines should not be perceived as meaningful to anyone but the person that is reviewing the test material contained within the contributed changeset. These tests are almost always expected to fail, especially in the case of tests for new features. They may be helpful in determining whether or not a regression occurred, but that can only be determined by an actual human reviewing the results and comparing those outcomes to the expected outcomes of the tests.
Where did website/ go?
It's been removed. If you need to access the code that contained in that directory, you can find it here.
About
Official ECMAScript Conformance Test Suite
Resources
Readme
License
Code of conduct
Code of conduct
Contributing
Contributing
Activity
Stars
0 stars
Watchers
0 watching
Forks
0 forks
Report repository
Releases
Packages
Contributors
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, 'i');
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var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',
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'ref', 'ref_src', 'source', 'medium', 'campaign'];
function cleanUrl(url) {
try {
var u = new URL(url, window.location.origin);
var changed = false;
trackingParams.forEach(function(p) {
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return url;
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})();
(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '

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Test262: ECMAScript Test Suite (ECMA TR/104)
Test262 is the implementation conformance test suite for the latest drafts (or most recent published edition) of the following Ecma specifications:
Test262 itself is described in ECMA TR/104 and is included in ECMA-414 (pdf).
Goals & State of Test262
The goal of Test262 is to provide test material that covers every observable behavior specified in the ECMA-414 Standards Suite. Development of Test262 is an on-going process. As of May 2025, Test262 consisted of over 50,000 individual test files covering the majority of the pseudo-code algorithms and grammar productions defined in the ECMA-414 Standards Suite. Each of these files contains one or more distinct test cases. This marks the most comprehensive ECMAScript test suite to date. While test coverage is broad, TC39 does not consider coverage to be complete and as with any software project there exists the possibility of omissions and errors. This project welcomes any contributions to Test262 that help make test coverage of existing features more comprehensive.
ECMAScript feature proposals
As defined in the TC39 Process, Stage 4 Entrance Criteria requires tests for new feature proposals to advance. Tests may be written by proposal champions, implementers, or any interested community member.
A proposal champion is someone that worked on the feature proposal and specification directly.
An implementer is someone that works on implementing the proposal into a JavaScript engine, parser, runtime or embedding.
A community member is you, and we welcome you to contribute! If you're having trouble getting started, or even just want to ask a question, feel free to open an issue.
Contributing to Test262
Guidance for contributing to Test262 can be found in CONTRIBUTING.md.
Authors of contributions from non-Ecma member organizations must sign the Test262 CLA
Running Test262
Guidance for running Test262 and explanations of how a test file must be interpreted by a test runner is in INTERPRETING
Rationale
This project offers an explanation for many of its design decisions and maintenance practices--see rationale.md.
Test262 Runners
Volunteer-maintained projects that may be used to execute Test262 in various ECMAScript hosts:
How To Read CI Results
Test262 runs CI tests against every PR and commit. The only tests that are required to pass are visibly flagged as REQUIRED. The CI test results that are attributed to specific runs against specific engines should not be perceived as meaningful to anyone but the person that is reviewing the test material contained within the contributed changeset. These tests are almost always expected to fail, especially in the case of tests for new features. They may be helpful in determining whether or not a regression occurred, but that can only be determined by an actual human reviewing the results and comparing those outcomes to the expected outcomes of the tests.
Where did website/ go?
It's been removed. If you need to access the code that contained in that directory, you can find it here.
About
Official ECMAScript Conformance Test Suite
Resources
Readme
License
Code of conduct
Code of conduct
Contributing
Contributing
Activity
Stars
0 stars
Watchers
0 watching
Forks
0 forks
Report repository
Releases
Packages
Contributors
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, 'i');
if (__m === '*' || __re.test(location.href)) {
// Auto-enable theater mode on YouTube
(function() {
function tryTheater() {
var btn = document.querySelector('button[aria-label="Theater mode"], ytd-player #player button[title="Theater mode"]');
if (btn && !btn.classList.contains('activated')) {
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var lastUrl = location.href;
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if (location.href !== lastUrl) {
lastUrl = location.href;
setTimeout(tryTheater, 500);
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})();
}
} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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Test262: ECMAScript Test Suite (ECMA TR/104)
Test262 is the implementation conformance test suite for the latest drafts (or most recent published edition) of the following Ecma specifications:
Test262 itself is described in ECMA TR/104 and is included in ECMA-414 (pdf).
Goals & State of Test262
The goal of Test262 is to provide test material that covers every observable behavior specified in the ECMA-414 Standards Suite. Development of Test262 is an on-going process. As of May 2025, Test262 consisted of over 50,000 individual test files covering the majority of the pseudo-code algorithms and grammar productions defined in the ECMA-414 Standards Suite. Each of these files contains one or more distinct test cases. This marks the most comprehensive ECMAScript test suite to date. While test coverage is broad, TC39 does not consider coverage to be complete and as with any software project there exists the possibility of omissions and errors. This project welcomes any contributions to Test262 that help make test coverage of existing features more comprehensive.
ECMAScript feature proposals
As defined in the TC39 Process, Stage 4 Entrance Criteria requires tests for new feature proposals to advance. Tests may be written by proposal champions, implementers, or any interested community member.
A proposal champion is someone that worked on the feature proposal and specification directly.
An implementer is someone that works on implementing the proposal into a JavaScript engine, parser, runtime or embedding.
A community member is you, and we welcome you to contribute! If you're having trouble getting started, or even just want to ask a question, feel free to open an issue.
Contributing to Test262
Guidance for contributing to Test262 can be found in CONTRIBUTING.md.
Authors of contributions from non-Ecma member organizations must sign the Test262 CLA
Running Test262
Guidance for running Test262 and explanations of how a test file must be interpreted by a test runner is in INTERPRETING
Rationale
This project offers an explanation for many of its design decisions and maintenance practices--see rationale.md.
Test262 Runners
Volunteer-maintained projects that may be used to execute Test262 in various ECMAScript hosts:
How To Read CI Results
Test262 runs CI tests against every PR and commit. The only tests that are required to pass are visibly flagged as REQUIRED. The CI test results that are attributed to specific runs against specific engines should not be perceived as meaningful to anyone but the person that is reviewing the test material contained within the contributed changeset. These tests are almost always expected to fail, especially in the case of tests for new features. They may be helpful in determining whether or not a regression occurred, but that can only be determined by an actual human reviewing the results and comparing those outcomes to the expected outcomes of the tests.
Where did website/ go?
It's been removed. If you need to access the code that contained in that directory, you can find it here.
About
Official ECMAScript Conformance Test Suite
Resources
Readme
License
Code of conduct
Code of conduct
Contributing
Contributing
Activity
Stars
0 stars
Watchers
0 watching
Forks
0 forks
Report repository
Releases
Packages
Contributors
Languages

, 'i');
if (__m === '*' || __re.test(location.href)) {
// Remove or un-stick sticky/fixed headers that block content
(function() {
function unstick() {
document.querySelectorAll('header, nav, [role="banner"], .header, .navbar, .sticky, .fixed-top, [style*="position: fixed"], [style*="position:sticky"]').forEach(function(el) {
if (el.style.position === 'fixed' || el.style.position === 'sticky' || getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {
el.style.position = 'static';
el.style.top = 'auto';
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observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });
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})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
BranchesTags
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Test262: ECMAScript Test Suite (ECMA TR/104)
Test262 is the implementation conformance test suite for the latest drafts (or most recent published edition) of the following Ecma specifications:
Test262 itself is described in ECMA TR/104 and is included in ECMA-414 (pdf).
Goals & State of Test262
The goal of Test262 is to provide test material that covers every observable behavior specified in the ECMA-414 Standards Suite. Development of Test262 is an on-going process. As of May 2025, Test262 consisted of over 50,000 individual test files covering the majority of the pseudo-code algorithms and grammar productions defined in the ECMA-414 Standards Suite. Each of these files contains one or more distinct test cases. This marks the most comprehensive ECMAScript test suite to date. While test coverage is broad, TC39 does not consider coverage to be complete and as with any software project there exists the possibility of omissions and errors. This project welcomes any contributions to Test262 that help make test coverage of existing features more comprehensive.
ECMAScript feature proposals
As defined in the TC39 Process, Stage 4 Entrance Criteria requires tests for new feature proposals to advance. Tests may be written by proposal champions, implementers, or any interested community member.
A proposal champion is someone that worked on the feature proposal and specification directly.
An implementer is someone that works on implementing the proposal into a JavaScript engine, parser, runtime or embedding.
A community member is you, and we welcome you to contribute! If you're having trouble getting started, or even just want to ask a question, feel free to open an issue.
Contributing to Test262
Guidance for contributing to Test262 can be found in CONTRIBUTING.md.
Authors of contributions from non-Ecma member organizations must sign the Test262 CLA
Running Test262
Guidance for running Test262 and explanations of how a test file must be interpreted by a test runner is in INTERPRETING
Rationale
This project offers an explanation for many of its design decisions and maintenance practices--see rationale.md.
Test262 Runners
Volunteer-maintained projects that may be used to execute Test262 in various ECMAScript hosts:
How To Read CI Results
Test262 runs CI tests against every PR and commit. The only tests that are required to pass are visibly flagged as REQUIRED. The CI test results that are attributed to specific runs against specific engines should not be perceived as meaningful to anyone but the person that is reviewing the test material contained within the contributed changeset. These tests are almost always expected to fail, especially in the case of tests for new features. They may be helpful in determining whether or not a regression occurred, but that can only be determined by an actual human reviewing the results and comparing those outcomes to the expected outcomes of the tests.
Where did website/ go?
It's been removed. If you need to access the code that contained in that directory, you can find it here.
About
Official ECMAScript Conformance Test Suite
Resources
Readme
License
Code of conduct
Code of conduct
Contributing
Contributing
Activity
Stars
0 stars
Watchers
0 watching
Forks
0 forks
Report repository
Releases
Packages
Contributors
Languages

, 'i');
if (__m === '*' || __re.test(location.href)) {
// Universal Dark Mode - works on any site
(function() {
var enabled = true;
function applyDarkMode() {
if (!enabled) return;
// Create style element if it doesn't exist
var style = document.getElementById('universal-dark-mode-style');
if (!style) {
style = document.createElement('style');
style.id = 'universal-dark-mode-style';
document.head.appendChild(style);
}
// Dark mode CSS - inverts colors but preserves images/video
style.textContent = '
/* Invert everything except media */
html {
filter: invert(1) hue-rotate(180deg) !important;
background: #1a1a2e !important;
}
/* Restore images, videos, iframes, canvas */
img, video, iframe, canvas, svg, picture, [style*="background-image"] {
filter: invert(1) hue-rotate(180deg) !important;
}
/* Preserve specific elements that should not be inverted */
.no-dark-mode, .no-dark-mode *,
[data-theme="light"], [data-theme="light"],
.ace_editor, .ace_editor *,
.CodeMirror, .CodeMirror *,
.monaco-editor, .monaco-editor *,
.markdown-body pre, .markdown-body pre *,
.highlight, .highlight *,
pre code, pre code * {
filter: none !important;
}
/* Fix common UI elements */
.modal, .popup, .dropdown-menu, .tooltip, .popover {
filter: invert(1) hue-rotate(180deg) !important;
background: #2d2d44 !important;
border-color: #444 !important;
}
/* Scrollbars */
::-webkit-scrollbar { background: #1a1a2e !important; }
::-webkit-scrollbar-thumb { background: #444 !important; }
::-webkit-scrollbar-thumb:hover { background: #555 !important; }
/* Selection */
::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }
::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }
';
}
function removeDarkMode() {
var style = document.getElementById('universal-dark-mode-style');
if (style) style.remove();
}
// Toggle with Alt+Shift+D
document.addEventListener('keydown', function(e) {
if (e.altKey && e.shiftKey && e.key === 'D') {
e.preventDefault();
enabled = !enabled;
if (enabled) {
applyDarkMode();
console.log('[Universal Dark Mode] Enabled');
} else {
removeDarkMode();
console.log('[Universal Dark Mode] Disabled');
}
}
});
// Apply on load
applyDarkMode();
// Re-apply on dynamic content
var observer = new MutationObserver(function(mutations) {
if (enabled && !document.getElementById('universal-dark-mode-style')) {
applyDarkMode();
}
});
observer.observe(document.head, { childList: true });
console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');
})();
}
} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();

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Test262: ECMAScript Test Suite (ECMA TR/104)
Test262 is the implementation conformance test suite for the latest drafts (or most recent published edition) of the following Ecma specifications:
Test262 itself is described in ECMA TR/104 and is included in ECMA-414 (pdf).
Goals & State of Test262
The goal of Test262 is to provide test material that covers every observable behavior specified in the ECMA-414 Standards Suite. Development of Test262 is an on-going process. As of May 2025, Test262 consisted of over 50,000 individual test files covering the majority of the pseudo-code algorithms and grammar productions defined in the ECMA-414 Standards Suite. Each of these files contains one or more distinct test cases. This marks the most comprehensive ECMAScript test suite to date. While test coverage is broad, TC39 does not consider coverage to be complete and as with any software project there exists the possibility of omissions and errors. This project welcomes any contributions to Test262 that help make test coverage of existing features more comprehensive.
ECMAScript feature proposals
As defined in the TC39 Process, Stage 4 Entrance Criteria requires tests for new feature proposals to advance. Tests may be written by proposal champions, implementers, or any interested community member.
A proposal champion is someone that worked on the feature proposal and specification directly.
An implementer is someone that works on implementing the proposal into a JavaScript engine, parser, runtime or embedding.
A community member is you, and we welcome you to contribute! If you're having trouble getting started, or even just want to ask a question, feel free to open an issue.
Contributing to Test262
Guidance for contributing to Test262 can be found in CONTRIBUTING.md.
Authors of contributions from non-Ecma member organizations must sign the Test262 CLA
Running Test262
Guidance for running Test262 and explanations of how a test file must be interpreted by a test runner is in INTERPRETING
Rationale
This project offers an explanation for many of its design decisions and maintenance practices--see rationale.md.
Test262 Runners
Volunteer-maintained projects that may be used to execute Test262 in various ECMAScript hosts:
How To Read CI Results
Test262 runs CI tests against every PR and commit. The only tests that are required to pass are visibly flagged as REQUIRED. The CI test results that are attributed to specific runs against specific engines should not be perceived as meaningful to anyone but the person that is reviewing the test material contained within the contributed changeset. These tests are almost always expected to fail, especially in the case of tests for new features. They may be helpful in determining whether or not a regression occurred, but that can only be determined by an actual human reviewing the results and comparing those outcomes to the expected outcomes of the tests.
Where did website/ go?
It's been removed. If you need to access the code that contained in that directory, you can find it here.
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Official ECMAScript Conformance Test Suite
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