In JS, @type for class property declarations is ignored unless the default value is contained in parentheses

[AlCalzone]

TypeScript Version: 3.1.0-dev.20180906

Search Terms: js class property type

Code

class Foo {
	constructor() {
		/** @type {Record<string, number>} */
		this.bar = {}; // has type {[x: string]: any}

		/** @type {Record<string, number>} */
		this.baz = ({}); // has type {Record<string, number>}
	}
}

Expected behavior:
bar and baz both have the declared type.
Actual behavior:
Only baz has the declared type.

Related Issues: possibly 26743

[ghost]

This seems to be working for me in typescript@next -- this.bar.foo = ""; will fail with Type '""' is not assignable to type 'number'..

[AlCalzone]

I must be doing something wrong then

// package.json
{
  "name": "repro",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "author": "",
  "license": "ISC",
  "dependencies": {
    "typescript": "^3.1.0-dev.20180906"
  }
}

// tsconfig.json
{
  "compilerOptions": {
    "target": "es5",
    "module": "commonjs",
    "allowJs": true,
    "checkJs": true,
  }
}

[ghost]

I did reproduce the error with [email protected]. Are you sure your editor is set up to use typescript@next?

[AlCalzone]

Thanks, that works indeed. Its kinda hard to switch versions in a js-only project due to the missing button with the TS version.