svelte-check-native

svelte-check-native is a high-performance command-line interface (CLI) type-checker specifically designed for Svelte projects. It serves as a drop-in replacement for svelte-check, maintaining compatibility with the same flags, output formats, and exit codes. This tool is built with Rust and leverages tsgo, making it ideal for:

• AI agents that require rapid feedback loops
• Efficient CI/CD pipelines
• Reliable Git pre-commit hooks

What it is and what it isn't

Performance

When tested on a SvelteKit + TypeScript monorepo containing 1,359 .svelte files, the performance metrics are as follows:
Command executed: svelte-check-native --tsconfig tsconfig.json --diagnostic-sources 'js,svelte'

Installation

To install svelte-check-native, execute the following command:

npm i -D svelte-check-native @typescript/native-preview

The package @typescript/native-preview denotes the tsgo binary, essential for the checking process.

Usage

To utilize svelte-check-native, run:

npx svelte-check-native --workspace .

Alternatively, script it into your package.json:

{
  "scripts": {
    "check": "svelte-check-native --workspace ."
  }
}

This tool supports the same flags as svelte-check. For assistance, use:

npx svelte-check-native --help

How it Works

The type-checking process involves:

1. Parsing each .svelte file into script and template sections.
2. Emitting a corresponding .svelte.ts overlay file.
3. Executing tsgo against the overlay TypeScript configuration.
4. Running the svelte/compiler for warnings via parallel processing.
5. Mapping diagnostics back to the original .svelte file.

Flags and Environment Variables

Various flags are available for customized operation:

--workspace <path>
--tsconfig <path>
--output <fmt>
--threshold <level>
--fail-on-warnings
--diagnostic-sources <list>
--compiler-warnings <list>
--ignore <globs>
--color / --no-color
--timings
--debug-paths
--tsgo-version
--tsgo-diagnostics
--emit-ts

For detailed functionality, reviewing the output of svelte-check-native --help is recommended.

Additional environment variables may also influence the tool's behavior, such as TSGO_BIN for overriding tsgo discovery paths.

Troubleshooting

In case of stale errors after modifying tsconfig.json, the following command can be run to clear the cache:

rm -rf node_modules/.cache/svelte-check-native

Roadmap

Future features include CSS support for enhanced versatility.

For developers requiring speed and accuracy in type-checking their Svelte applications, svelte-check-native provides an efficient, Rust-optimized solution that seamlessly integrates into existing workflows.