feat(project): add command stub

Author: honghuangdc

src/command/stub.ts

@@ -0,0 +1,132 @@
+import { mkdir, writeFile } from 'node:fs/promises';
+import { dirname, relative, resolve } from 'pathe';
+import { resolvePath } from 'mlly';
+
+// 定义自己的类型
+interface StubContext {
+  options: {
+    rootDir: string;
+    outDir: string;
+    declaration?: 'compatible' | 'node16' | boolean;
+  };
+  pkg: {
+    name?: string;
+    type?: 'module' | 'commonjs';
+    exports?: Record<string, any>;
+  };
+}
+
+// 简单的warn函数
+function warn(ctx: StubContext, message: string): void {
+  console.warn(`[rolldown] ${message}`);
+}
+
+interface ExportConfig {
+  import?: string;
+  require?: string;
+  default?: string;
+  [key: string]: any;
+}
+type ExportsMap = Record<string, string | ExportConfig>;
+
+export async function rolldownStub(ctx: StubContext): Promise<void> {
+  const exports = ctx.pkg.exports as ExportsMap;
+  if (!exports) {
+    warn(ctx, 'No exports field found in package.json, skipping stub generation');
+    return;
+  }
+
+  // 计算 tsx 路径（相对 outDir）
+  const tsxESMPath = relative(
+    resolve(ctx.options.rootDir, ctx.options.outDir),
+    await resolvePath('tsx', { url: import.meta.url, conditions: ['node', 'import'] })
+  );
+  const tsxCJSPath = relative(
+    resolve(ctx.options.rootDir, ctx.options.outDir),
+    await resolvePath('tsx', { url: import.meta.url, conditions: ['node', 'require'] })
+  );
+
+  await processExports(ctx, exports, tsxESMPath, tsxCJSPath);
+}
+
+async function processExports(
+  ctx: StubContext,
+  exports: ExportsMap,
+  tsxESMPath: string,
+  tsxCJSPath: string
+): Promise<void> {
+  const outDir = resolve(ctx.options.rootDir, ctx.options.outDir);
+  await mkdir(outDir, { recursive: true });
+
+  for (const [exportPath, exportConfig] of Object.entries(exports)) {
+    const config: ExportConfig = typeof exportConfig === 'string' ? { import: exportConfig } : exportConfig;
+
+    await generateStubForExport(ctx, exportPath, config, outDir, tsxESMPath, tsxCJSPath);
+  }
+}
+
+async function generateStubForExport(
+  ctx: StubContext,
+  exportPath: string,
+  exportConfig: ExportConfig,
+  outDir: string,
+  tsxESMPath: string,
+  tsxCJSPath: string
+): Promise<void> {
+  const sourcePath = exportConfig.import || exportConfig.require || exportConfig.default;
+  if (!sourcePath) {
+    warn(ctx, `No source path found for export: ${exportPath}`);
+    return;
+  }
+  if (sourcePath.includes('*')) {
+    warn(ctx, `Wildcard export not supported: ${exportPath}`);
+    return;
+  }
+
+  const resolvedSourcePath = resolve(ctx.options.rootDir, sourcePath.replace(/^\.\//, ''));
+  const relativeSourcePath = relative(outDir, resolvedSourcePath);
+  const outputBase = resolve(outDir, exportPath);
+  const outputDir = dirname(outputBase);
+  await mkdir(outputDir, { recursive: true });
+
+  // 生成ESM stub
+  if (exportConfig.import || exportConfig.default) {
+    const esmStub = generateESMStub(relativeSourcePath, tsxESMPath);
+    await writeFile(`${outputBase}.mjs`, esmStub);
+  }
+  // 生成CJS stub
+  if (exportConfig.require || exportConfig.default) {
+    const cjsStub = generateCJSStub(relativeSourcePath, tsxCJSPath);
+    await writeFile(`${outputBase}.cjs`, cjsStub);
+  }
+  // 生成类型声明文件
+  if (ctx.options.declaration) {
+    const dtsContent = generateDTSStub(relativeSourcePath);
+    await writeFile(`${outputBase}.d.ts`, dtsContent);
+  }
+}
+
+function generateESMStub(sourcePath: string, tsxESMPath: string): string {
+  return [
+    `import { tsImport } from ${JSON.stringify(`${tsxESMPath}/esm/api`)};`,
+    '',
+    `const _module = await tsImport(new URL(${JSON.stringify(sourcePath)}, import.meta.url), import.meta.url);`,
+    `export default _module?.default ?? _module;`
+  ].join('\n');
+}
+
+function generateCJSStub(sourcePath: string, tsxCJSPath: string): string {
+  return [
+    `const tsx = require(${JSON.stringify(`${tsxCJSPath}/cjs/api`)});`,
+    '',
+    `const _module = tsx.require(require('path').resolve(__dirname, ${JSON.stringify(sourcePath)}));`,
+    `module.exports = _module?.default ?? _module;`
+  ].join('\n');
+}
+
+function generateDTSStub(sourcePath: string): string {
+  return [
+    `export * from ${JSON.stringify(sourcePath)};`,
+    `export { default } from ${JSON.stringify(sourcePath)};`
+  ].join('\n');
+}