Move types from jsdoc quickfix (instead of copy)

Search Terms

• jsdoc quickfix
• 80004

Suggestion

There's a great quickfix available to copy JSDoc type annotations to TypeScript annotations:

When you do this, however, you still have type annotations in your JSDoc. This is duplicative and is likely to lead to the types getting out of sync over time. It's best to avoid putting type information in JSDoc once you're using TypeScript.

I'd like a quickfix that annotates types and removes the types from the JSDoc.

Use Cases

This would be helpful for any project converting from JavaScript to TypeScript. You should convert your JSDoc types to TypeScript types and you should remove types from your JSDoc once you do. This sort of quickfix would help people get to the right place.

Examples

/**
 * @param a {string} Base string.
 * @param b {string=} Optional string to add
 * @return {string}
 */
function foo(a, b) {
  if (b) return a + b;
  return a;
}

should get converted to:

/**
 * @param a Base string.
 * @param b Optional string to add
 */
function foo(a: string, b?: string): string {
  if (b) return a + b;
  return a;
}

rather than:

/**
 * @param a {string} Base string.
 * @param b {string=} Optional string to add
 * @return {string}
 */
function foo(a: string, b: string | undefined): string {
  if (b) return a + b;
  return a;
}

Checklist

My suggestion meets these guidelines:

• 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 by locating the existing JSDoc quickfix associated with search term 80004 and trace how it converts JSDoc types into TypeScript annotations. Use the example as the acceptance target: move the types into the function signature while removing the type information from the JSDoc, including the return annotation.