@greffon/vite

The build plugin of Greffon, expression trees for TypeScript. At build time it validates each query lambda against the expression subset and reifies it into __expr({...}): the tree inlined as a plain object, the original function kept alongside as compiled. An out-of-subset lambda gets a coded diagnostic (R1103 for ==, …); every code has an entry in the error reference.

The plugin uses only Rollup-compatible hooks, so the same export runs unchanged in Vite, Rollup, and Rolldown.

Install

npm install -D @greffon/vite

Usage

// vite.config.ts
import { greffon } from "@greffon/vite";

export default {
  plugins: [greffon()],
};

That is the whole setup. Lambdas at traced query call sites (db.users.filter(u => u.age >= 18)) and expr() wrappers reify; everything else in the module is left alone, and a second pass over already-transformed code is a no-op.

Options

All optional, passed as greffon({ … }):

• packages: import sources whose query methods are traced. Default ["@greffon/query"].
• include / exclude: RegExp filters on module ids. Defaults /\.[cm]?[jt]sx?$/ and /node_modules/.
• diagnostics: "error" fails the build, "warn" prints. Default "error" in build, "warn" in dev.
• emitSource: keep the original lambda text on the tree as src. Default "dev": on in serve, off in build.
• globals: extra identifiers treated as safe globals during capture.

Without the plugin

In-memory querying works with no plugin at all: the memory provider calls your compiled lambda and never reads the tree, so the same query files run unchanged under Vitest. A provider that needs the tree (SQL, anything remote) does require the plugin — or the dev-only runtime fallback, @greffon/fallback. Compiling with tsc and no bundler, use @greffon/ts-transformer.

Docs

• Getting started
• The subset
• The boundary rule

License

MIT