TypeScript 4.4 Iteration Plan

[DanielRosenwasser]

This document outlines our focused tasks for TypeScript 4.4. It minimally indicates intent to investigate tasks or contribute to an implementation. Nothing is set in stone, but we will strive to complete them in a reasonable timeframe.

Date	Event
May 25th	TypeScript 4.3 Release
June 25th	Create 4.4 Beta (4.4.0) Build for Testing
June 29th	TypeScript 4.4 Beta Release
August 6th	Create 4.4 RC (4.4.1) Build for Testing
August 10th	TypeScript 4.4 RC Release
August 20th	Create 4.4 Final (4.4.2) Build for Testing
August 24th	TypeScript 4.4 Final Release 🚀

Language and Compiler Features

• Stricter Optional/Missing vs. Undefined
• Generalized Index Signatures
• Strictness Flag for unknown in catch
• Investigate Incremental Warm-up Strategies
• --help Menu Updates
• Review the Project Setup Experience
• Investigate/Prototype Node.js 12 ESM Support
• lib.d.ts Updates

Editor Productivity

• Inline Hints
• Commit Characters in Server API
• Differentiate Definitions in References
• VS Code Welcome Screen Improvements
• Investigate High-Confidence "Did you Mean?" in JS
• Continue Enabling the Language Server Protocol (LSP)
• Investigate Debug Inline Values API

Performance

• Supporting Additional Trace Points
• Profiling/Tracing Mode Improvements
• Investigate Tooling for JIT Deoptimizations
• Use fs.realpathSync.native

Infrastructure

• Expand Perf Suite
• Fuzzer Improvements and Addressing Crashes
• Improving User Suite Reports
• master -> main
• Migrate to modules

Website

• Continue smoothing out first user experience
• Streamline website calls-to-action
• Gather UX feedback on playground
• Fix display issues on sample error spans

DefinitelyTyped

• Continue improving processes and performance

[DanielRosenwasser]

The 4.3 Iteration Plan can be found at #42762

[mrlubos]

I yearn for a day when I see #241 on the list 😔

[xiaoxiangmoe]

@DanielRosenwasser #40694 This feature is also marked Milestone TypeScript 4.4.0. Are we going to implement it in ts 4.4 too?

[canonic-epicure]

I'd like to draw some attention to the #7342

• issue was filed in Mar 2016
• there are ~170 emoji reactions in the thread
• there are ~10 duplicates of this issue (did not count emoji reactions in all of them)
• there's PR, which fixes this issue and passes all CI checks, submitted in Jan
• the PR works great (verified by me in my project)

The #7342 fix will be a solid quality of life improvement for many users, I believe it should be considered for 4.4.0.

[ghiscoding]

ohhhh "Inline Hints", what a productivity boost that will bring..... bring it on!!! 🚀

[Kingwl]

ohhhh "Inline Hints", what a productivity boost that will bring..... bring it on!!! 🚀

Let's get it down! I'll update the PR.

[DanielRosenwasser]

@typescript-bot create release-4.4

[typescript-bot]

Heya @DanielRosenwasser, the branch 'release-4.4' already seems to exist on microsoft/TypeScript. You should prepare it for the release by hand.

[DanielRosenwasser]

No.

@typescript-bot create release-4.4

[typescript-bot]

Heya @DanielRosenwasser, I've started to create the release-4.4 branch for you. Here's the link to my best guess at the log.

[Kingwl]

Hey. Welcome back.😉

[DanielRosenwasser]

@typescript-bot sync release-4.4

[typescript-bot]

Heya @DanielRosenwasser, I've started to sync release-4.4 with main for you. Here's the link to my best guess at the log.

[ExE-Boss]

The “Breaking Changes” section should include:

• Indirect calls for imported functions #44624

[DanielRosenwasser]

@typescript-bot sync release-4.4

[typescript-bot]

Heya @DanielRosenwasser, I've started to sync release-4.4 with main for you. Here's the link to my best guess at the log.

[DanielRosenwasser]

Had to do a manual merge because I guess main had an LKG.

@typescript-bot bump release-4.4

[typescript-bot]

Heya @DanielRosenwasser, I've started to update the version number on release-4.4 to 4.4.1-rc for you. Here's the link to my best guess at the log.

[DanielRosenwasser]

The 4.5 Iteration Plan has now been posted at #45418

[DanielRosenwasser]

@typescript-bot bump release-4.4

[typescript-bot]

Heya @DanielRosenwasser, I've started to update the version number on release-4.4 to 4.4.2 for you. Here's the link to my best guess at the log.

[DanielRosenwasser]

Just as a heads up - the RC went out 2 days later, so we're going to target a release date of August 26th.

[DanielRosenwasser]

@typescript-bot bump release-4.4

[typescript-bot]

Heya @DanielRosenwasser, I've started to update the version number on release-4.4 to 4.4.3 for you. Here's the link to my best guess at the log.

[DanielRosenwasser]

Caught a regression in --build mode - we think we can back-port it to TypeScript 4.4.

@typescript-bot bump release-4.4

[typescript-bot]

Heya @DanielRosenwasser, I've started to update the version number on release-4.4 to 4.4.4 for you. Here's the link to my best guess at the log.

[DanielRosenwasser]

4.4.4

😈