Disallow implicit boolean casting of strings and numbers about typescript-eslint HOT 6 CLOSED

strict-boolean-expressions is now available: https://github.com/typescript-eslint/typescript-eslint/blob/master/packages/eslint-plugin/docs/rules/strict-boolean-expressions.md

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flow supports this via their sketchy-null rules.
https://flow.org/en/docs/linting/rule-reference/#toc-sketchy-null

Speaking from experience over my last few months at facebook, it's actually really, really annoying; most engineers I've spoken to hate it!

But if there is demand from the community, it's a rule we could look into.

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We’re interested in doing this in GitHub Desktop: desktop/desktop#3538. I tried to add a rule in desktop/desktop#3550, but the type information available was limited, and @iAmWillShepherd suggested that we try to write this rule with TSLint instead.

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the type information available was limited

I suppose you'd need to use the Language Service API to access accurate type information, especially when you're accessing properties that were defined in a separate file. Not sure how easy it'd be to integrate that into ESLint's lifecycle.

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Bump! I would love to see this too. This could be added as an option for the no-implicit-coercion rule's boolean property, because if (x) does an implicit boolean conversion, just the same as !!x.

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As a temporary workaround, one can use @typescript-eslint/eslint-plugin-tslint with tslint rule strict-boolean-expressions (https://github.com/palantir/tslint/blob/master/src/rules/strictBooleanExpressionsRule.ts).

I miss this feature from Flow and would love to see this as a rule. Chatter I saw on the TypeScript tracker indicated it is unlikely to be added to the compiler.

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