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chore: add CONTRIBUTING.md
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fix: lint-fix CONTRIBUTING.md
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185 changes: 185 additions & 0 deletions CONTRIBUTING.md
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# Contributing to Svelte Language Tools

Svelte Language Tools provides IDE support for Svelte files through the Language Server Protocol (LSP). It powers the [VSCode extension](https://marketplace.visualstudio.com/items?itemName=svelte.svelte-vscode) and enables Svelte support in [numerous other IDEs](https://microsoft.github.io/language-server-protocol/implementors/tools/).

The [Open Source Guides](https://opensource.guide/) website has a collection of resources for individuals, communities, and companies. These resources help people who want to learn how to run and contribute to open source projects. Contributors and people new to open source alike will find the following guides especially useful:

- [How to Contribute to Open Source](https://opensource.guide/how-to-contribute/)
- [Building Welcoming Communities](https://opensource.guide/building-community/)

## Get involved

There are many ways to contribute to Svelte Language Tools, and many of them do not involve writing any code. Here's a few ideas to get started:

- Simply start using Svelte Language Tools in your IDE. Does everything work as expected? If not, we're always looking for improvements. Let us know by [opening an issue](#reporting-new-issues).
- Look through the [open issues](https://github.com/sveltejs/language-tools/issues). A good starting point would be issues tagged [good first issue](https://github.com/sveltejs/language-tools/issues?q=is%3Aissue+is%3Aopen+label%3A%22good+first+issue%22). Provide workarounds, ask for clarification, or suggest labels. Help triage issues.
- If you find an issue you would like to fix, [open a pull request](#pull-requests).
- Read through our [documentation](https://github.com/sveltejs/language-tools/tree/master/docs). If you find anything that is confusing or can be improved, you can make edits by opening a pull request.
- Take a look at the [features requested](https://github.com/sveltejs/language-tools/labels/enhancement) by others in the community and consider opening a pull request if you see something you want to work on.

Contributions are very welcome. If you think you need help planning your contribution, please reach out to us on [Discord](https://svelte.dev/chat) and let us know you are looking for a bit of help.

## Development

This is a monorepo managed with [`pnpm workspaces`](https://pnpm.io/workspaces/). Install pnpm globally with:

```sh
npm i -g pnpm
```

Clone the repository and install dependencies:

```sh
git clone [email protected]:sveltejs/language-tools.git
cd language-tools
pnpm install
pnpm bootstrap
```

### Building

To build all packages:

```sh
pnpm build
```

To watch for changes:

```sh
pnpm watch
```

### Code structure

#### Packages

- [`packages/language-server`](packages/language-server) - The language server for Svelte.
- [`packages/svelte-vscode`](packages/svelte-vscode) - The official VSCode extension for Svelte
- [`packages/svelte2tsx`](packages/svelte2tsx) - Converts `.svelte` files into legal TypeScript/JSX. Want to see how it's transformed? [Check out this REPL](https://embed.plnkr.co/plunk/JPye9tlsqwMrWHGv?show=preview&autoCloseSidebar)
- [`packages/svelte-check`](packages/svelte-check) - CLI tool for type checking and diagnostics

#### Key entry points

- `packages/language-server/src/server.ts` - Language server entry point
- `packages/language-server/src/plugins/` - Language service plugins (TypeScript, Svelte, CSS, HTML)
- `packages/svelte2tsx/src/svelte2tsx/index.ts` - Svelte to TSX transformation
- `packages/svelte-vscode/src/extension.ts` - VSCode extension entry point

#### High Level Overview

```mermaid
flowchart LR
%% IDEs
VSC[IDE: VSCode + Svelte for VS Code extension]
click VSC "https://github.com/sveltejs/language-tools/tree/master/packages/svelte-vscode" "Svelte for VSCode extension"
%% Tools
CLI[CLI: svelte-check]
click CLI "https://github.com/sveltejs/language-tools/tree/master/packages/svelte-check" "A command line tool to get diagnostics for Svelte code"
%% Svelte - Extensions
VSC_TSSP[typescript-svelte-plugin]
click VSC_TSSP "https://github.com/sveltejs/language-tools/tree/master/packages/typescript-plugin" "A TypeScript plugin for Svelte intellisense"
%% Svelte - Packages
SVELTE_LANGUAGE_SERVER["svelte-language-server"]
SVELTE_COMPILER_SERVICE["svelte2tsx"]
TS_SERVICE["TS/JS intellisense using TypeScript language service"]
SVELTE_SERVICE["Svelte intellisense using Svelte compiler"]
click SVELTE_LANGUAGE_SERVER "https://github.com/sveltejs/language-tools/tree/master/packages/language-server" "A language server adhering to the LSP"
click SVELTE_COMPILER_SERVICE "https://github.com/sveltejs/language-tools/tree/master/packages/language-server/src/plugins/svelte" "Transforms Svelte code into JSX/TSX code"
click TS_SERVICE "https://github.com/sveltejs/language-tools/tree/master/packages/language-server/src/plugins/typescript"
click SVELTE_SERVICE "https://github.com/sveltejs/language-tools/tree/master/packages/language-server/src/plugins/svelte"
%% External Packages
HTML_SERVICE[HTML intellisense using vscode-html-languageservice]
CSS_SERVICE[CSS intellisense using vscode-css-languageservice]
VSC_TS[vscode-typescript-language-features]
click HTML_SERVICE "https://github.com/microsoft/vscode-html-languageservice"
click CSS_SERVICE "https://github.com/microsoft/vscode-css-languageservice"
click VSC_TS "https://github.com/microsoft/vscode/tree/main/extensions/typescript-language-features"
subgraph EMBEDDED_SERVICES[Embedded Language Services]
direction LR
TS_SERVICE
SVELTE_SERVICE
HTML_SERVICE
CSS_SERVICE
end
VSC -- Language Server Protocol --> SVELTE_LANGUAGE_SERVER
CLI -- Only using diagnostics feature --> SVELTE_LANGUAGE_SERVER
VSC -- includes --> VSC_TS
VSC_TS -- loads --> VSC_TSSP
VSC_TSSP -- uses --> SVELTE_COMPILER_SERVICE
TS_SERVICE -- uses --> SVELTE_COMPILER_SERVICE
SVELTE_LANGUAGE_SERVER -- bundles --> EMBEDDED_SERVICES
```

More information about the internals can be found [HERE](./docs/internal/overview.md).

### Running tests

Run tests for all packages:

```sh
pnpm test
```

Run tests for a specific package:

```sh
cd packages/[package-name]
pnpm test
```

### Testing in VSCode

To test your changes in VSCode:

1. Open the repository in VSCode
2. Go to the debug panel (Ctrl+Shift+D / Cmd+Shift+D)
3. Select "Run VSCode Extension" from the dropdown
4. Press F5 to launch a new VSCode instance with your changes

This launches a new VSCode window and a watcher for your changes. In this dev window you can choose an existing Svelte project to work against. When you make changes to `svelte-vscode` use the command "Reload Window" in the VSCode command palette to see your changes. When you make changes to `language-server` use the command "Svelte: Restart Language Server". When you make changes to `svelte2tsx`, you first need to run `pnpm build` within its folder, then restart the language server. When you make changes to`typescript-plugin`, you need to first run `pnpm build` within its folder and then use the command "TypeScript: Restart Server".

#### Testing in other editors

For other editors, you'll need to build the language server and configure your editor to use the local build. See the documentation for your specific editor.

### Linking local changes

To test certain local changes in a Svelte project, you might want to use [pnpm `overrides`](https://pnpm.io/package_json#pnpmoverrides) in your project's `package.json`:

```jsonc
{
"pnpm": {
"overrides": {
// Test changes to svelte-check:
"svelte-check": "link:../path/to/language-tools/packages/svelte-check",
// You only need this if you're testing the changes with an editor other than VS Code:
"svelte-language-server": "link:../path/to/language-tools/packages/language-server"
}
}
}
```

## Pull requests

Small pull requests are much easier to review and more likely to get merged. Make sure the PR does only one thing, otherwise please split it.

Please make sure the following is done when submitting a pull request:

1. Fork [the repository](https://github.com/sveltejs/language-tools) and create your branch from `master`.
2. Describe your test plan in your pull request description. Make sure to test your changes.
3. Make sure your code lints (`pnpm lint`).
4. Make sure your tests pass (`pnpm test`).
5. Make sure your code is properly formatted (`pnpm format`).

If you're only fixing a bug, it's fine to submit a pull request right away but we still recommend that you file an issue detailing what you're fixing. This is helpful in case we don't accept that specific fix but want to keep track of the issue.

All pull requests should be opened against the `master` branch.

## License

By contributing to Svelte Language Tools, you agree that your contributions will be licensed under its [MIT license](LICENSE).

## Questions?

Join us in the [Svelte Discord](https://svelte.dev/chat) and post your question.
124 changes: 2 additions & 122 deletions README.md
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Expand Up @@ -42,129 +42,9 @@ Which is a mix of [HTMLx](https://github.com/htmlx-org/HTMLx) and vanilla JavaSc

This repo contains the tools which provide editor integrations for Svelte files like this.

## Packages

This repo uses [`pnpm workspaces`](https://pnpm.io/workspaces/), which TLDR means if you want to run a command in each project then you can either `cd` to that directory and run the command, or use `pnpm -r [command]`.

For example `pnpm -r test`.

#### [`svelte-language-server`](packages/language-server)

The language server for Svelte. Built from [UnwrittenFun/svelte-language-server](https://github.com/UnwrittenFun/svelte-language-server) and heavily inspired by [Vetur](https://github.com/vuejs/vetur) to become the official language server for the language.

#### [`svelte-check`](packages/svelte-check)

A command line tool to check your svelte files for type errors, unused css, and more. Built from [Vetur's VTI](https://github.com/vuejs/vetur/tree/master/vti).

#### [`svelte-vscode`](packages/svelte-vscode)

The official vscode extension for Svelte. Built from [UnwrittenFun/svelte-vscode](https://github.com/UnwrittenFun/svelte-vscode) to become the official vscode extension for the language.

#### [`svelte2tsx`](packages/svelte2tsx)

Converts a .svelte file into a legal TypeScript file. Built from [halfnelson/svelte2tsx](https://github.com/halfnelson/svelte2tsx) to provide the auto-complete and import mapping inside the language server.

> Want to see how it's transformed? [Check out this REPL](https://embed.plnkr.co/plunk/JPye9tlsqwMrWHGv?show=preview&autoCloseSidebar)

## Development

### High Level Overview

```mermaid
flowchart LR
%% IDEs
VSC[IDE: VSCode + Svelte for VS Code extension]
click VSC "https://github.com/sveltejs/language-tools/tree/master/packages/svelte-vscode" "Svelte for VSCode extension"
%% Tools
CLI[CLI: svelte-check]
click CLI "https://github.com/sveltejs/language-tools/tree/master/packages/svelte-check" "A command line tool to get diagnostics for Svelte code"
%% Svelte - Extensions
VSC_TSSP[typescript-svelte-plugin]
click VSC_TSSP "https://github.com/sveltejs/language-tools/tree/master/packages/typescript-plugin" "A TypeScript plugin for Svelte intellisense"
%% Svelte - Packages
SVELTE_LANGUAGE_SERVER["svelte-language-server"]
SVELTE_COMPILER_SERVICE["svelte2tsx"]
TS_SERVICE["TS/JS intellisense using TypeScript language service"]
SVELTE_SERVICE["Svelte intellisense using Svelte compiler"]
click SVELTE_LANGUAGE_SERVER "https://github.com/sveltejs/language-tools/tree/master/packages/language-server" "A language server adhering to the LSP"
click SVELTE_COMPILER_SERVICE "https://github.com/sveltejs/language-tools/tree/master/packages/language-server/src/plugins/svelte" "Transforms Svelte code into JSX/TSX code"
click TS_SERVICE "https://github.com/sveltejs/language-tools/tree/master/packages/language-server/src/plugins/typescript"
click SVELTE_SERVICE "https://github.com/sveltejs/language-tools/tree/master/packages/language-server/src/plugins/svelte"
%% External Packages
HTML_SERVICE[HTML intellisense using vscode-html-languageservice]
CSS_SERVICE[CSS intellisense using vscode-css-languageservice]
VSC_TS[vscode-typescript-language-features]
click HTML_SERVICE "https://github.com/microsoft/vscode-html-languageservice"
click CSS_SERVICE "https://github.com/microsoft/vscode-css-languageservice"
click VSC_TS "https://github.com/microsoft/vscode/tree/main/extensions/typescript-language-features"
subgraph EMBEDDED_SERVICES[Embedded Language Services]
direction LR
TS_SERVICE
SVELTE_SERVICE
HTML_SERVICE
CSS_SERVICE
end
VSC -- Language Server Protocol --> SVELTE_LANGUAGE_SERVER
CLI -- Only using diagnostics feature --> SVELTE_LANGUAGE_SERVER
VSC -- includes --> VSC_TS
VSC_TS -- loads --> VSC_TSSP
VSC_TSSP -- uses --> SVELTE_COMPILER_SERVICE
TS_SERVICE -- uses --> SVELTE_COMPILER_SERVICE
SVELTE_LANGUAGE_SERVER -- bundles --> EMBEDDED_SERVICES
```

More information about the internals can be found [HERE](./docs/internal/overview.md).

#### Setup

Pull requests are encouraged and always welcome. [Pick an issue](https://github.com/sveltejs/language-tools/issues?q=is%3Aissue+is%3Aopen+sort%3Aupdated-desc) and help us out!

To install and work on these tools locally:

> Make sure to uninstall the extension from the marketplace to not have it clash with the local one.

```bash
git clone https://github.com/sveltejs/language-tools.git svelte-language-tools
cd svelte-language-tools
pnpm install
pnpm bootstrap
```

> Do not use npm to install the dependencies, as the specific package versions in `pnpm-lock.yaml` are used to build and test Svelte.

To build all of the tools, run:

```bash
pnpm build
```

The tools are written in [TypeScript](https://www.typescriptlang.org/), but don't let that put you off — it's basically just JavaScript with type annotations. You'll pick it up in no time. If you're using an editor other than [Visual Studio Code](https://code.visualstudio.com/) you may need to install a plugin in order to get syntax highlighting and code hints etc.

#### Making Changes

There are two ways to work on this project: either by working against an existing project or entirely through tests.

## Running the Dev Language Server Against Your App

To run the developer version of both the language server and the VSCode extension:

- open the root of this repo in VSCode
- Go to the debugging panel
- Make sure "Run VSCode Extension" is selected, and hit run

This launches a new VSCode window and a watcher for your changes. In this dev window you can choose an existing Svelte project to work against. If you don't use pure Javascript and CSS, but languages like Typescript or SCSS, your project will need a [Svelte preprocessor setup](docs#using-with-preprocessors). When you make changes to the extension or language server you can use the command "Reload Window" in the VSCode command palette to see your changes. When you make changes to `svelte2tsx`, you first need to run `pnpm build` within its folder.

### Running Tests

You might think that as a language server, you'd need to handle a lot of back and forth between APIs, but actually it's mostly high-level JavaScript objects which are passed to the [npm module vscode-languageserver](https://code.visualstudio.com/api/language-extensions/language-server-extension-guide).

This means it's easy to write tests for your changes:

```bash
pnpm test
```
## Contributing

For trickier issues, you can run the tests with a debugger in VSCode by setting a breakpoint (or adding `debugger` in the code) and launching the test in the [JavaScript Debug Terminal](https://code.visualstudio.com/docs/nodejs/nodejs-debugging#_javascript-debug-terminal).
Contributions are encouraged and always welcome. [Read the contribution guide for more info](CONTRIBUTING.md) and help us out!

## Supporting Svelte

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