是否有 ESLint 规则来防止真实检查

Question

I want to avoid accidentally invoking Javascript's insane truthy system. Are there any ESLint rules to help with this? Especially in if statements. For example:

const a: number = 0;
const b: string | null = null;
if (a) { ... } // Should be an error.
if (b) { ... } // Should be an error.
if (a !== 0) { ... } // Ok
if (b !== null) { ... } // Ok

I thought no-implicit-coercion might do the job but it seems like it doesn't cover this case.

Answer 1

Not sure if there is a rule that will do that, but if there is it will need to be a typescript-eslint rule. Javascript alone doesn't have enough information to statically determine if coercion will happen. You can see the typescript-eslint rules here: https://github.com/typescript-eslint/typescript-eslint/tree/master/packages/eslint-plugin/src/rules