chore: backup export

src/generate-export-v0.9.0.ts

@@ -0,0 +1,42 @@
+import type { Analyzed } from './analyze'
+
+export interface ExportsRuntime {
+  polyfill: string
+  exportDeclaration: string
+}
+
+export function generateExport(analyzed: Analyzed): ExportsRuntime | null {
+  if (!analyzed.exports.length) {
+    return null
+  }
+
+  const memberDefault = analyzed.exports
+    // Find `module.exports` or `exports.default`
+    .find(exp => exp.token.left === 'module' || exp.token.right === 'default')
+
+  let members = analyzed.exports
+    // Exclude `module.exports` and `exports.default`
+    .filter(exp => exp.token.left !== 'module' && exp.token.right !== 'default')
+    .map(exp => exp.token.right)
+  // Remove duplicate export
+  members = [...new Set(members)]
+
+  const membersDeclaration = members.map(
+    m => `const __CJS__export_${m}__ = (module.exports == null ? {} : module.exports).${m}`,
+  )
+  const membersExport = members.map(m => `__CJS__export_${m}__ as ${m}`)
+  if (memberDefault) {
+    membersDeclaration.unshift(`const __CJS__export_default__ = (module.exports == null ? {} : module.exports).default || module.exports`)
+    membersExport.unshift('__CJS__export_default__ as default')
+  }
+
+  return {
+    polyfill: 'var module = { exports: {} }; var exports = module.exports;',
+    exportDeclaration: `
+${membersDeclaration.join(';\n')};
+export {
+  ${membersExport.join(',\n  ')},
+}
+`.trim(),
+  }
+}