facebook/flow v0.218.0

on GitHub

Likely to cause new Flow errors:

• We start to validate variance inside $ReadOnly, which is previously completely unchecked. It also results in Flow complaining about some incorrect bounds. example

New Features:

• Hover types will now show a specialized version of the callee expression at a call to a generic or intersection-typed function.

Notable bug fixes:

• improve coverage accuracy for the element access portion on element calls, obj[m](arg).

Misc:

• We slightly optimized Flow's performance of subtyping check between two union types.

Library Definitions:

• Add defintions Array.prototype.findLastIndex(), String.prototype.at(), TypedArray.prototype.at() and Object.hasOwn() (thanks @pascalduez).
• Update URL defintions (thanks @pascalduez).
• Add typing for cause option in Error constructor.