`ts
import { readFileSync } from 'node:fs'
import { readFile } from '@quansync/fs'
import { quansync } from 'quansync'
import type { Plugin } from 'unloader'

// sync usage
const pluginSync: Plugin = {
name: 'my-plugin',
resolveId(source, importer, options) {
const result = this.resolve(${source}.js, importer, options)
if (result) {
console.log(result)
return result
}
},
load(id) {
const contents = readFileSync(id, 'utf8')
console.log(contents)
return contents
},
}

// quansync usage
const pluginQuansync: Plugin = {
name: 'my-plugin',
resolveId: quansync(function* (source, importer, options) {
const result = yield this.resolve(${source}.js, importer, options)
if (result) {
console.log(result)
return result
}
}),
load: quansync(function* (id) {
const contents = yield readFile(id, 'utf8')
console.log(contents)
return contents
}),
}
`

`ts
let context: PluginContext

export function demoPlugin(): Plugin {
return {
name: 'demo-plugin',
options(config) {
config.sourcemap = true
},
buildStart(_context) {
context = _context
context.log('hello world')
},
async resolveId(source, importer, options) {
if (source.startsWith('node:')) return

// Feature: virtual module
if (source === 'virtual-mod') {
return '/virtual-mod'
}

// Feature: try resolve with different extensions
const result = await this.resolve(${source}.js, importer, options)
if (result) return result
},

load(id) {
if (id === '/virtual-mod') {
return { code: 'export const count = 42' }
}
},
transform(code, id) {
if (typeof code === 'string') {
// Feature: source map
const s = new MagicString(code)
s.prepend('// header\n')
const map = s.generateMap({
file: id,
hires: 'boundary',
includeContent: true,
})
return {
code: s.toString(),
map,
}
}
},
}
}
`