checkJs should recognize properties assigned with lodash

Search Terms

js, lodash, properties

Suggestion

Recognize properties of some object when using lodash assign method

Use Cases

Any initalization of an object using:

_.assign(obj, { ...someProps });

// Instead of
this.oneProp = oneProp;
this.anotherProp = anotherProp;

Examples

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.

The issue describes TypeScript checkJs behavior for properties assigned through lodash's assign method, but names no source files, tests, or entry points. Start by reproducing the example in a focused checkJs test and trace how property assignments are recognized; done means the lodash pattern is type-checked without changing emitted JavaScript.