WIP experimental swc compiler

compilers/swc.js

@@ -0,0 +1 @@
+module.exports = require('../dist/compilers/swc')

package.json

@@ -20,7 +20,8 @@
     "./esm": "./esm.mjs",
     "./esm.mjs": "./esm.mjs",
     "./esm/transpile-only": "./esm/transpile-only.mjs",
-    "./esm/transpile-only.mjs": "./esm/transpile-only.mjs"
+    "./esm/transpile-only.mjs": "./esm/transpile-only.mjs",
+    "./compilers/swc": "./compilers/swc.js"
   },
   "types": "dist/index.d.ts",
   "bin": {
@@ -107,9 +108,14 @@
     "util.promisify": "^1.0.1"
   },
   "peerDependencies": {
+    "@swc/core": ">=1.2.38",
     "typescript": ">=2.7"
   },
+  "optionalDependencies": {
+    "@swc/core": ">=1.2.38"
+  },
   "dependencies": {
+    "@swc/core": ">=1.2.38",
     "arg": "^4.1.0",
     "diff": "^4.0.1",
     "make-error": "^1.1.1",

src/compilers/swc.ts

@@ -0,0 +1,53 @@
+import type * as ts from 'typescript'
+import * as swc from '@swc/core'
+import { JscTarget } from '@swc/core'
+
+export const transpileModule: typeof ts.transpileModule = (input: string, transpileOptions: ts.TranspileOptions): ts.TranspileOutput => {
+  const compilerOptions = transpileOptions.compilerOptions!
+  const { fileName } = transpileOptions
+  const { esModuleInterop, sourceMap, importHelpers, experimentalDecorators, emitDecoratorMetadata, target, jsxFactory, jsxFragmentFactory } = compilerOptions
+  const { code, map } = swc.transformSync(input, {
+    filename: fileName,
+    sourceMaps: sourceMap,
+    // isModule: true,
+    module: {
+      type: 'commonjs',
+      noInterop: !esModuleInterop
+    },
+    swcrc: false,
+    jsc: {
+      externalHelpers: importHelpers,
+      parser: {
+        syntax: 'typescript',
+        tsx: fileName!.endsWith('.tsx') || fileName!.endsWith('.jsx'),
+        decorators: experimentalDecorators,
+        dynamicImport: true
+      },
+      target: targetMapping.get(target!) ?? 'es3',
+      transform: {
+        decoratorMetadata: emitDecoratorMetadata,
+        legacyDecorator: true,
+        react: {
+          throwIfNamespace: false,
+          development: false,
+          useBuiltins: false,
+          pragma: jsxFactory!,
+          pragmaFrag: jsxFragmentFactory!,
+        }
+      }
+    }
+  })
+  return { outputText: code, sourceMapText: map }
+}
+
+const targetMapping = new Map<ts.ScriptTarget, JscTarget>()
+targetMapping.set(/* ts.ScriptTarget.ES3 */ 0, 'es3')
+targetMapping.set(/* ts.ScriptTarget.ES5 */ 1, 'es5')
+targetMapping.set(/* ts.ScriptTarget.ES2015 */ 2, 'es2015')
+targetMapping.set(/* ts.ScriptTarget.ES2016 */ 3, 'es2016')
+targetMapping.set(/* ts.ScriptTarget.ES2017 */ 4, 'es2017')
+targetMapping.set(/* ts.ScriptTarget.ES2018 */ 5, 'es2018')
+targetMapping.set(/* ts.ScriptTarget.ES2019 */ 6, 'es2019')
+targetMapping.set(/* ts.ScriptTarget.ES2020 */ 7, 'es2019')
+targetMapping.set(/* ts.ScriptTarget.ESNext */ 99, 'es2019')
+targetMapping.set(/* ts.ScriptTarget.Latest */ 99, 'es2019')