Martin Probst
f0826cfeaa
TypeScript must hoist accessors for super properties when converting async method bodies to the `__awaiter` pattern for targets before ES2016. Previously, TypeScript would reify all property accesses into element accesses, i.e. convert the property name into a string parameter and pass it to `super[...]`. That breaks optimizers like Closure Compiler or Uglify in advanced mode, when property renaming is enabled, as it mixes quoted and un-quoted property access (`super['x']` vs just `x` at the declaration site). This change creates a variable `_superProps` that contains accessors for each property accessed on super within the async method. This allows accessing the properties by name (instead of quoted string), which fixes the quoted/unquoted confusion. The change keeps the generic accessor for element access statements to match quoting behaviour. Fixes #21088.
TypeScript
TypeScript is a language for application-scale JavaScript. TypeScript adds optional types to JavaScript that support tools for large-scale JavaScript applications for any browser, for any host, on any OS. TypeScript compiles to readable, standards-based JavaScript. Try it out at the playground, and stay up to date via our blog and Twitter account.
Installing
For the latest stable version:
npm install -g typescript
For our nightly builds:
npm install -g typescript@next
Contribute
There are many ways to contribute to TypeScript.
- Submit bugs and help us verify fixes as they are checked in.
- Review the source code changes.
- Engage with other TypeScript users and developers on StackOverflow.
- Join the #typescript discussion on Twitter.
- Contribute bug fixes.
- Read the language specification (docx, pdf, md).
This project has adopted the Microsoft Open Source Code of Conduct. For more information see the Code of Conduct FAQ or contact opencode@microsoft.com with any additional questions or comments.
Documentation
Building
In order to build the TypeScript compiler, ensure that you have Git and Node.js installed.
Clone a copy of the repo:
git clone https://github.com/Microsoft/TypeScript.git
Change to the TypeScript directory:
cd TypeScript
Install Jake tools and dev dependencies:
npm install -g jake
npm install
Use one of the following to build and test:
jake local # Build the compiler into built/local
jake clean # Delete the built compiler
jake LKG # Replace the last known good with the built one.
# Bootstrapping step to be executed when the built compiler reaches a stable state.
jake tests # Build the test infrastructure using the built compiler.
jake runtests # Run tests using the built compiler and test infrastructure.
# You can override the host or specify a test for this command.
# Use host=<hostName> or tests=<testPath>.
jake runtests-browser # Runs the tests using the built run.js file. Syntax is jake runtests. Optional
parameters 'host=', 'tests=[regex], reporter=[list|spec|json|<more>]'.
jake baseline-accept # This replaces the baseline test results with the results obtained from jake runtests.
jake lint # Runs tslint on the TypeScript source.
jake help # List the above commands.
Usage
node built/local/tsc.js hello.ts
Roadmap
For details on our planned features and future direction please refer to our roadmap.