generate-exports.js

export function wrapCode(magicString, uses, moduleName, HELPERS_NAME, virtualDynamicRequirePath) {
  const args = `module${uses.exports ? ', exports' : ''}`;

  magicString
    .trim()
    .prepend(`var ${moduleName} = ${HELPERS_NAME}.createCommonjsModule(function (${args}) {\n`)
    .append(
      `\n}${virtualDynamicRequirePath ? `, ${JSON.stringify(virtualDynamicRequirePath)}` : ''});`
    );
}

export function rewriteExportsAndGetExportsBlock(
  magicString,
  moduleName,
  wrapped,
  topLevelModuleExportsAssignments,
  topLevelExportsAssignmentsByName,
  defineCompiledEsmExpressions,
  deconflict,
  isRestorableCompiledEsm,
  code,
  uses,
  HELPERS_NAME,
  defaultIsModuleExports
) {
  const namedExportDeclarations = [`export { ${moduleName} as __moduleExports };`];
  const moduleExportsPropertyAssignments = [];
  let deconflictedDefaultExportName;

  if (!wrapped) {
    let hasModuleExportsAssignment = false;
    const namedExportProperties = [];

    // Collect and rewrite module.exports assignments
    for (const { left } of topLevelModuleExportsAssignments) {
      hasModuleExportsAssignment = true;
      magicString.overwrite(left.start, left.end, `var ${moduleName}`);
    }

    // Collect and rewrite named exports
    for (const [exportName, node] of topLevelExportsAssignmentsByName) {
      const deconflicted = deconflict(exportName);
      magicString.overwrite(node.start, node.left.end, `var ${deconflicted}`);

      if (exportName === 'default') {
        deconflictedDefaultExportName = deconflicted;
      } else {
        namedExportDeclarations.push(
          exportName === deconflicted
            ? `export { ${exportName} };`
            : `export { ${deconflicted} as ${exportName} };`
        );
      }

      if (hasModuleExportsAssignment) {
        moduleExportsPropertyAssignments.push(`${moduleName}.${exportName} = ${deconflicted};`);
      } else {
        namedExportProperties.push(`\t${exportName}: ${deconflicted}`);
      }
    }

    // Regenerate CommonJS namespace
    if (!hasModuleExportsAssignment) {
      const moduleExports = `{\n${namedExportProperties.join(',\n')}\n}`;
      magicString
        .trim()
        .append(
          `\n\nvar ${moduleName} = ${
            isRestorableCompiledEsm
              ? `/*#__PURE__*/Object.defineProperty(${moduleExports}, '__esModule', {value: true})`
              : moduleExports
          };`
        );
    }
  }

  // Generate default export
  const defaultExport = [];
  if (defaultIsModuleExports === 'auto') {
    if (isRestorableCompiledEsm) {
      defaultExport.push(`export default ${deconflictedDefaultExportName || moduleName};`);
    } else if (
      (wrapped || deconflictedDefaultExportName) &&
      (defineCompiledEsmExpressions.length > 0 || code.includes('__esModule'))
    ) {
      // eslint-disable-next-line no-param-reassign
      uses.commonjsHelpers = true;
      defaultExport.push(
        `export default /*@__PURE__*/${HELPERS_NAME}.getDefaultExportFromCjs(${moduleName});`
      );
    } else {
      defaultExport.push(`export default ${moduleName};`);
    }
  } else if (defaultIsModuleExports === true) {
    defaultExport.push(`export default ${moduleName};`);
  } else if (defaultIsModuleExports === false) {
    if (deconflictedDefaultExportName) {
      defaultExport.push(`export default ${deconflictedDefaultExportName};`);
    } else {
      defaultExport.push(`export default ${moduleName}.default;`);
    }
  }

  return `\n\n${defaultExport
    .concat(namedExportDeclarations)
    .concat(moduleExportsPropertyAssignments)
    .join('\n')}`;
}