facebook/flow v0.313.0

on GitHub

Likely to cause new Flow errors:

• Flow has changed its casting syntax from (x: T) to x as T. The default value of the option casting_syntax is now as, and Flow will error on the old syntax. If you want to preserve the old defualt value, add casting_syntax=both to your .flowconfig. You can use the npm package flow-upgrade to upgade: yarn run flow-codemod typeCastToAsExpression. Read the docs for more.

New Features:

• Exported class setters no longer require an explicit type annotation: void is used if omitted

Parser:

• The flow-parser estree output now aligns more with hermes-parser: ArrayExpression gains a trailingComma field, optional chaining is wrapped in a ChainExpression, AssertNonnull (expr!) emits a NonNullExpression instead of an optional node, type-position this emits ThisTypeAnnotation, and TypeParameter.bound is now a bare type node without the TypeAnnotation wrapper.