facebook/flow v0.202.0

on GitHub

Likely to cause new Flow errors:

• Don't error for tuple element type incompatibility if we have already errored for invalid tuple arity.
• Fix a bug that causes certain errors in annotations to be hidden. As a result, more legitimate errors might appear. Example here.

New Features:

• Add support for optional tuple elements, e.g. ['s'] and ['s', 1] are both valid values for [foo: string, bar?: number].
• Add autocomplete for keywords to the LSP.
• Add a code action that inserts jsdoc on a function.
• exact_by_default=true is now the default value if the option is omitted from the .flowconfig. Read this blog post for more details.

Notable bug fixes:

• Fix LSP rename command to consider aliased named exports.
• If a contextually typed parameter has a default, we will filter out null and void from the inferred type of the parameter. This removes spurious errors like this.
• Some spurious prop-missing errors might be removed. Example here
• Remove some spurious internal errors of Flow. Example here

Misc:

• Add option for module.system.haste.module_ref_prefix_LEGACY_INTEROP in the config to allow migration from the automatic_require_default flag and to ES module syntax.

Parser:

• Include InterpreterDirective in the AST.
• Fix loc/range of postfix arrays that start with a parenthesis, like (A | B)[].
• Fix missing error when arrow functions have duplicate params.