Starting this issue to track what needs to be done for the 1.4 release:

TypeScript support:

• Add TypeScript to the help
• Bundle the dependencies Split bundle before shipping to npm #1640

TypeScript formatting blockers:

• Comments inside decorator arguments are moved to the wrong line #1460 Comments inside of decoratos
• Missing AST Type #1694 Comments inside of function types
• Unstable yield re-print with TypeScript parser #1769 generator functions
• Missing default modifier for TSNamespaceExportDeclaration eslint/typescript-eslint-parser#288
• Incorrect optional flag on Identifier eslint/typescript-eslint-parser#289
• Missing computed flag on TSMethodSignature eslint/typescript-eslint-parser#290
• Async generator method is not flagged as a generator eslint/typescript-eslint-parser#297

Facebook blockers:

• Do not break on extends #1520 Do not break on extend
• !() indentation #774 !() indentation
• Inline import from for a single one like we do for require
• Update to flow 0.47.0
• Extra space in flow type #1724 Extra space in flow type

Things that are easy we should knock down:

• Forces variable declarations onto single line #1607 Make multiple variable declarations on their own line

It's going to be pretty awesome :)