Ts Compiler to Swc Config: respects decorators config and SWCRC=true

packages/core/index.ts

@@ -32,26 +32,28 @@ function transformOption(path: string, options?: Options, jest = false): SwcOpti
   opts.esModuleInterop = opts.esModuleInterop ?? true
   return {
     filename: path,
-    jsc: {
-      target: opts.target ?? DEFAULT_ES_TARGET,
-      externalHelpers: jest ? true : false,
-      parser: {
-        syntax: 'typescript' as const,
-        tsx: typeof opts.jsx !== 'undefined' ? opts.jsx : path.endsWith('.tsx'),
-        decorators: Boolean(opts.experimentalDecorators),
-        dynamicImport: Boolean(opts.dynamicImport),
-      },
-      transform: {
-        legacyDecorator: Boolean(opts.experimentalDecorators),
-        decoratorMetadata: Boolean(opts.emitDecoratorMetadata),
-        react: options?.react,
-        hidden: {
-          jest,
+    jsc: options?.swc?.swcrc
+      ? undefined
+      : {
+          target: opts.target ?? DEFAULT_ES_TARGET,
+          externalHelpers: jest ? true : false,
+          parser: {
+            syntax: 'typescript' as const,
+            tsx: typeof opts.jsx !== 'undefined' ? opts.jsx : path.endsWith('.tsx'),
+            decorators: Boolean(opts.experimentalDecorators),
+            dynamicImport: Boolean(opts.dynamicImport),
+          },
+          transform: {
+            legacyDecorator: Boolean(opts.experimentalDecorators),
+            decoratorMetadata: Boolean(opts.emitDecoratorMetadata),
+            react: options?.react,
+            hidden: {
+              jest,
+            },
+          },
+          keepClassNames: opts.keepClassNames,
+          paths: opts.paths,
         },
-      },
-      keepClassNames: opts.keepClassNames,
-      paths: opts.paths,
-    },
     minify: false,
     isModule: true,
     module: {

packages/register/__test__/ts-compiler-options-to-swc-config.spec.ts

@@ -0,0 +1,161 @@
+import { join } from 'path'
+
+import test from 'ava'
+import * as ts from 'typescript'
+
+import { tsCompilerOptionsToSwcConfig } from '../read-default-tsconfig'
+
+test('default values', (t) => {
+  const options: ts.CompilerOptions = {}
+  const filename = 'some-file.tsx'
+  const swcConfig = tsCompilerOptionsToSwcConfig(options, filename)
+  const expected = {
+    module: 'es6',
+    sourcemap: false,
+    experimentalDecorators: false,
+    emitDecoratorMetadata: false,
+    esModuleInterop: false,
+    swc: {
+      filename,
+      inputSourceMap: undefined,
+      sourceRoot: undefined,
+      jsc: {
+        externalHelpers: false,
+        parser: {
+          syntax: 'typescript',
+          tsx: true,
+          dynamicImport: true,
+          decorators: undefined,
+        },
+        paths: {},
+        keepClassNames: true,
+        target: 'es2018',
+        transform: {
+          decoratorMetadata: undefined,
+          legacyDecorator: undefined,
+          react: undefined,
+        },
+      },
+    },
+  }
+  t.deepEqual(swcConfig, expected)
+})
+
+test('should set the decorator config', (t) => {
+  const options: ts.CompilerOptions = {
+    experimentalDecorators: true,
+    emitDecoratorMetadata: true,
+  }
+  const filename = 'some-file.ts'
+  const swcConfig = tsCompilerOptionsToSwcConfig(options, filename)
+  const expected = {
+    experimentalDecorators: true,
+    emitDecoratorMetadata: true,
+    swc: {
+      filename,
+      jsc: {
+        parser: {
+          decorators: true,
+        },
+        transform: {
+          decoratorMetadata: true,
+          legacyDecorator: true,
+        },
+      },
+    },
+  }
+  t.like(swcConfig, expected)
+})
+
+test('should force the jsx  config', (t) => {
+  const options: ts.CompilerOptions = {
+    jsx: ts.JsxEmit.ReactJSX,
+  }
+  const filename = 'some-file.ts'
+  const swcConfig = tsCompilerOptionsToSwcConfig(options, filename)
+  const expected = {
+    module: 'es6',
+    swc: {
+      filename,
+      jsc: {
+        parser: {
+          tsx: true,
+        },
+        transform: {
+          react: {
+            pragma: options.jsxFactory,
+            pragmaFrag: options.jsxFragmentFactory,
+            importSource: 'react',
+            runtime: 'automatic',
+            useBuiltins: true,
+          },
+        },
+      },
+    },
+  }
+  t.like(swcConfig, expected)
+})
+
+test('should set all values', (t) => {
+  const options: ts.CompilerOptions = {
+    module: ts.ModuleKind.CommonJS,
+    target: ts.ScriptTarget.ES5,
+    sourceMap: true,
+    esModuleInterop: true,
+    inlineSourceMap: true,
+    sourceRoot: 'source-root',
+    importHelpers: true,
+    jsx: ts.JsxEmit.None,
+    experimentalDecorators: true,
+    emitDecoratorMetadata: true,
+    paths: {
+      '@test': ['./specific-path-1/test'],
+      '@another': ['./specific-path-2/another'],
+    },
+    jsxFactory: 'jsx-factory',
+    jsxFragmentFactory: 'jsx-fragment-factory',
+    jsxImportSource: 'jsx-import-source',
+    baseUrl: './packages/register/__test__',
+  }
+  const filename = 'some-file.tsx'
+  const swcConfig = tsCompilerOptionsToSwcConfig(options, filename)
+  const expected = {
+    module: 'commonjs',
+    sourcemap: options.sourceMap,
+    experimentalDecorators: options.experimentalDecorators,
+    emitDecoratorMetadata: options.emitDecoratorMetadata,
+    esModuleInterop: options.esModuleInterop,
+    swc: {
+      filename,
+      inputSourceMap: options.inlineSourceMap,
+      sourceRoot: options.sourceRoot,
+      jsc: {
+        externalHelpers: options.importHelpers,
+        parser: {
+          syntax: 'typescript',
+          tsx: true,
+          dynamicImport: true,
+          decorators: options.experimentalDecorators,
+        },
+        paths: {
+          '@test': [join(__dirname, './specific-path-1/test')],
+          '@another': [join(__dirname, './specific-path-2/another')],
+        },
+        keepClassNames: true,
+        target: 'es5',
+        transform: {
+          decoratorMetadata: options.emitDecoratorMetadata,
+          legacyDecorator: options.experimentalDecorators,
+          react: {
+            pragma: options.jsxFactory,
+            pragmaFrag: options.jsxFragmentFactory,
+            importSource: options.jsxImportSource,
+            runtime: 'classic',
+            useBuiltins: true,
+          },
+        },
+      },
+    },
+  }
+  t.deepEqual(swcConfig, expected)
+})

packages/register/read-default-tsconfig.ts

@@ -115,6 +115,7 @@ export function tsCompilerOptionsToSwcConfig(options: ts.CompilerOptions, filena
           syntax: 'typescript',
           tsx: isJsx,
           dynamicImport: true,
+          decorators: options.experimentalDecorators,
         },
         paths: Object.fromEntries(
           Object.entries(options.paths ?? {}).map(([aliasKey, aliasPaths]) => [
@@ -125,6 +126,8 @@ export function tsCompilerOptionsToSwcConfig(options: ts.CompilerOptions, filena
         keepClassNames: true,
         target: toTsTarget(options.target ?? ts.ScriptTarget.ES2018),
         transform: {
+          decoratorMetadata: options.emitDecoratorMetadata,
+          legacyDecorator: options.experimentalDecorators,
           react:
             options.jsxFactory || options.jsxFragmentFactory || options.jsx || options.jsxImportSource
               ? {