diff --git a/README.md b/README.md index d80559b47..20c561339 100644 --- a/README.md +++ b/README.md @@ -1,207 +1,8 @@ -# Tsickle - TypeScript to Closure Translator [![Build Status](https://github.com/angular/tsickle/actions/workflows/node.js.yml/badge.svg)](https://github.com/angular/tsickle/actions/workflows/node.js.yml) +# Tsickle - TypeScript to Closure Translator -Tsickle converts TypeScript code into a form acceptable to the [Closure -Compiler]. This allows using TypeScript to transpile your sources, and then -using Closure Compiler to bundle and optimize them, while taking advantage of -type information in Closure Compiler. +The tsickle repository is unsupported and will not be updated. It has been [officially unsupported](https://github.com/angular/tsickle/commit/3bf8d97c6bd53a920eb4f9b4d18cb584ead48e5a) since November 2022, has not seen any new commits to master since December 2023, and will be frozen starting May 2024. We generally cannot support using tsickle to integrate with Closure Compiler outside of the Google ecosystem due to the complexity of the toolchain. -[closure compiler]: https://github.com/google/closure-compiler/ +This repository will remain publicly available to fork. -## What conversion means +Previous version of this README can be found [here](https://github.com/angular/tsickle/blob/3bf8d97c6bd53a920eb4f9b4d18cb584ead48e5a/README.md). -A (non-exhaustive) list of the sorts of transformations Tsickle applies: - -- inserts Closure-compatible JSDoc annotations on functions/classes/etc -- converts ES6 modules into `goog.module` modules -- generates externs.js from TypeScript d.ts (and `declare`, see below) -- declares types for class member variables -- translates `export * from ...` into a form Closure accepts -- converts TypeScript enums into a form Closure accepts -- reprocesses all jsdoc to strip Closure-invalid tags - -In general the goal is that you write valid TypeScript and Tsickle handles -making it valid Closure Compiler code. - -## Warning: unsupported - -Google uses tsickle internally to minify its apps (including those using -Angular) using Closure Compiler. We have little experience using tsickle in the -other JavaScript ecosystems that are seen outside of Google, and there is -generally no support for using it from our side. - -## Usage - -Tsickle is a library, designed to be used by a larger program that interacts -with TypeScript and the Closure compiler. - -Some known clients are: - -1. Within Google we use tsickle inside the [Bazel build - system](https://bazel.build/). That code is published as - open source as part of [Bazel's nodejs/TypeScript - build rules](https://bazelbuild.github.io/rules_nodejs/). -1. [tscc](https://github.com/theseanl/tscc) wraps tsickle and - closure compiler, and interops with rollup. -1. We publish a simple demo program in the `demo/` subdirectory. - -## Design details - -### Output format - -Tsickle is designed to do whatever is necessary to make the code acceptable by -Closure compiler. We view its output as a necessary intermediate form for -communicating to the Closure compiler, and not something for humans. This means -the tsickle output may be kind of ugly to read. Its only real use is to pass it -on to the compiler. - -For one example, the syntax of types tsickle produces are specific to Closure. -The type `{!Foo}` means "Foo, excluding null" and a type alias becomes a `var` -statement that is tagged with `@typedef`. - -Tsickle emits modules using Closure's `goog.module` module system. This system -is similar to but different from ES modules, and was supported by Closure before -the ES module system was finalized. - -### Differences from TypeScript - -Closure and TypeScript are not identical. Tsickle hides most of the -differences, but users must still be aware of some differences. - -#### `declare` - -Any declaration in a `.d.ts` file, as well as any declaration tagged with -`declare ...`, is intepreted by Tsickle as a name that should be preserved -through Closure compilation (i.e. not renamed into something shorter). Use it -any time the specific string names of your fields are significant. That would -most often happen when the object either coming from outside your program, or -being passed out of the program. - -Example: - - declare interface JSONResult { - username: string; - } - let r = JSON.parse(input) as JSONResult; - console.log(r.username); - -By adding `declare` to the interface (or if it were in a `.d.ts` file), Tsickle -will inform Closure that it must use exactly the field name `.username` (and not -e.g. `.a`) in the output JS. This matters for this example because the input -JSON probably uses the string `'username'` and not whatever name Closure would -invent for it. (Note: `declare` on an interface has no additional meaning in -pure TypeScript.) - -#### Exporting decorators - -An exporting decorator is a decorator that has `@ExportDecoratedItems` in its -JSDoc. - -The names of elements that have an exporting decorator are preserved through -the Closure compilation process by applying an `@export` tag to them. - -Example: - - /** @ExportDecoratedItems */ - function myDecorator() { - // ... - } - - @myDecorator() - class DoNotRenameThisClass { ... } - -## Development - -### Dependencies - -- nodejs. Install from your operating system's package manger, by following - instructions on https://nodejs.org/en/, or by using - [NVM](https://github.com/nvm-sh/nvm) -- yarn. Install from your operating system's package manager or by following - [instructions on yarnpkg.com](https://yarnpkg.com/en/docs/install). - -### One-time setup - -Run `yarn` to install dependencies. - -### Build & Test commands - -- `yarn build` builds the code base. -- Run `tsc --watch` for an interactive, incremental, and continuous build. -- `yarn lint` checks for lint. -- `yarn test` runs unit tests, e2e tests and checks for lint (but make sure to - `yarn build` first or run tsc!). Set the `TESTBRIDGE_TEST_ONLY` environment - variable to filter what golden tests to run. - -### TypeScript AST help - -https://astexplorer.net/ and https://ts-ast-viewer.com/ are convenient tools to -visualize and inspect a TypeScript AST. - -### Debugging - -You can debug tests by passing `--node_options=--inspect` or -`--node_options=--inspect-brk` (to suspend execution directly after startup). - -For example, to debug a specific golden test: - -```shell -TESTBRIDGE_TEST_ONLY=my_golden_test node --inspect-brk=4332 ./node_modules/.bin/jasmine out/test/*.js -``` - -Then open [about:inspect] in Chrome and choose "about:inspect". Chrome will -launch a debugging session on any node process that starts with a debugger -listening on one of the listed ports. The tsickle tests and Chrome both default -to `localhost:9229`, so things should work out of the box. - -The break in specific code locations you can add `debugger;` statements in the -source code. - -### Updating Goldens - -Run `UPDATE_GOLDENS=y yarn test` to have the test suite update the goldens in -`test_files/...`. - -### Environment variables - -Set the environment variable `TESTBRIDGE_TEST_ONLY=` to limit the golden -tests (found in `test_files/...`) to only run tests with a name matching the -regex. - -### Releasing - -On a new branch, run: - -``` -# tsickle releases are all minor releases for now, see npm help version. -$ npm version minor -``` - -This will update the version in `package.json`, commit the changes, and -create a git tag. - -Push the branch, open a pull request, get it reviewed, and wait for it to be merged. - -Checkout and pull the latest version from master: - -``` -$ git checkout master && git pull -``` - -Check if the tag exists. If not, re-tag the commit and push the tag. - -``` -$ git tag -# Does this show the tag already? If not, proceed with: -$ git tag v0.32.0 && git push origin v0.32.0 # but use correct version -``` - -Once the versioned tag is pushed to GitHub the release (as found on -https://github.com/angular/tsickle/releases) will be implicitly created. - -From the master branch run: - -``` -npm config set registry https://wombat-dressing-room.appspot.com -npm login -npm publish # runs a clean build & test automatically -```