This is a monorepo, meaning the repo holds multiple packages. It requires the use of pnpm. You can install pnpm with:
npm i -g pnpm
pnpm
commands run in the project's root directory will run on all sub-projects. You can checkout the code and install the dependencies with:
git clone [email protected]:sveltejs/kit.git
cd kit
pnpm install
You can use the playground at playgrounds/basic
to experiment with your changes to SvelteKit locally.
If you want to test against an existing project, you can use pnpm overrides
in that project:
{
// ...
"pnpm": {
"overrides": {
"@sveltejs/kit": "link:../path/to/svelte-kit/packages/kit",
// additionally/optional the adapter you're using
"@sveltejs/adapter-auto": "link:../path/to/svelte-kit/packages/adapter-auto"
}
}
}
Entry points to be aware of are:
packages/create-svelte
- code that's run when you create a new project withnpm create svelte@latest
packages/package
- for thesvelte-package
commandpackages/kit/src/core
- code that's called at dev/build-timepackages/kit/src/core/sync
- forsvelte-kit sync
, which regenerates routing info and type definitionspackages/kit/src/runtime
- code that's called at runtimepackages/kit/src/exports/vite
- for all the Vite plugin related stuffpackages/adapter-[platform]
- for the various SvelteKit-provided adapters
If you're looking for an issue to tackle to get familiar with the codebase and test suite, the low hanging fruit label contains issues that ought to be relatively straightforward to fix. Check to see if a PR already exists for an issue before working on it!
Issues that have a clear solution but which may be slightly more involved have the ready to implement label.
Issues with the soon milestone are higher priority than issues with the later label (though PRs for 'later' issues are still welcome, especially if you're affected by them).
Run pnpm test
to run the tests from all subpackages. Browser tests live in subdirectories of packages/kit/test
such as packages/kit/test/apps/basics
.
You can run the tests for only a single package by first moving to that directory. E.g. cd packages/kit
.
For some packages you must rebuild each time before running the tests if you've made code changes. These packages have a build
command. Packages like packages/kit
don't require a build step.
To run a single integration test or otherwise control the running of the tests locally see the Playwright CLI docs. Note that you will need to run these commands from the test project directory such as packages/kit/test/apps/basics
.
You can run the test server with cd packages/kit/test/apps/basics; pnpm run dev
to hit it with your browser. The Playwright Inspector offers similar functionality.
You may need to install some dependencies first, e.g. with npx playwright install-deps
(which only works on Ubuntu).
If there are tests that fail on the CI, you can retrieve the failed screenshots by going to the summary page of the CI run. You can usually find this by clicking on "Details" of the check results, clicking "Summary" at the top-left corner, and then scrolling to the bottom "Artifacts" section to download the archive.
It is very easy to introduce flakiness in a browser test. If you try to fix the flakiness in a test, you can run it until failure to gain some confidence you've fixed the test with a command like:
npx playwright test --workers=1 --repeat-each 1000 --max-failures 1 -g "accepts a Request object"
If you would like to test local changes to Vite or another dependency, you can build it and then use pnpm.overrides
. Please note that pnpm.overrides
must be specified in the root package.json
and you must first list the package as a dependency in the root package.json
:
{
// ...
"dependencies": {
"vite": "^4.0.0"
},
"pnpm": {
"overrides": {
"vite": "link:../path/to/vite/packages/vite"
}
}
}
All documentation for SvelteKit is in the documentation
directory, and any improvements should be made as a Pull Request to this repository. The site itself is located in the sites/kit.svelte.dev
directory and can be run locally to preview changes.
There are a few guidelines we follow:
- Internal variables are written with
snake_case
while external APIs are written withcamelCase
- Provide a single object as the argument to public APIs. This object can have multiple properties
- Avoid creating new test projects under
packages/kit/test/apps
but reuse an existing one when possible - Ensure
pnpm lint
andpnpm check
pass. You can runpnpm format
to format the code
To use the git hooks in the repo, which will save you from waiting for CI to tell you that you forgot to lint, run this:
git config core.hookspath .githooks
For changes to be reflected in package changelogs, run pnpm changeset
and follow the prompts.
If your PR changes the generated types of SvelteKit, run pnpm generate:types
inside packages/kit
and commit the new output (don't format it with Prettier!). Review the changes carefully to ensure there are no unwanted changes. If you don't commit type changes, CI will fail.
The Changesets GitHub action will create and update a PR that applies changesets and publishes new versions of changed packages to npm.
New packages will need to be published manually the first time if they are scoped to the @sveltejs
organisation, by running this from the package directory:
npm publish --access=public