test-262 integration

Search Terms

test-262, test262

Suggestion

Run test-262 on TS downlevel

Use Cases

What do you want to use this for?

• Verify that downleveling is spec-compliant to avoid issues when changing the test target.

• Possible benefits for TS team:

  • Reduce triage overhead by catching semantic errors quickly
  • Reduce duplicate effort by putting creative testing work into the test-262 project

Examples

gulp runtests  # runs relevant test-262 tests

Checklist

• This wouldn't be a breaking change in existing TypeScript/JavaScript code
• This wouldn't change the runtime behavior of existing JavaScript code
• This could be implemented without emitting different JS based on the types of the expressions
• This isn't a runtime feature (e.g. library functionality, non-ECMAScript syntax with JavaScript output, etc.)
• This feature would agree with the rest of TypeScript's Design Goals.

Start with the test-262 project linked in the issue and the existing gulp runtests entry point. Determine how relevant test-262 tests would be selected and run against TypeScript downlevel output. Done means the integration runs successfully and can verify downlevel behavior against the test-262 suite.