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alert / js / node_modules / @babel / helper-split-export-declaration / lib / index.js
@Réz István Réz István on 18 Nov 2021 2 KB first commit
"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = splitExportDeclaration;

var t = require("@babel/types");

function splitExportDeclaration(exportDeclaration) {
  if (!exportDeclaration.isExportDeclaration()) {
    throw new Error("Only export declarations can be split.");
  }

  const isDefault = exportDeclaration.isExportDefaultDeclaration();
  const declaration = exportDeclaration.get("declaration");
  const isClassDeclaration = declaration.isClassDeclaration();

  if (isDefault) {
    const standaloneDeclaration = declaration.isFunctionDeclaration() || isClassDeclaration;
    const scope = declaration.isScope() ? declaration.scope.parent : declaration.scope;
    let id = declaration.node.id;
    let needBindingRegistration = false;

    if (!id) {
      needBindingRegistration = true;
      id = scope.generateUidIdentifier("default");

      if (standaloneDeclaration || declaration.isFunctionExpression() || declaration.isClassExpression()) {
        declaration.node.id = t.cloneNode(id);
      }
    }

    const updatedDeclaration = standaloneDeclaration ? declaration : t.variableDeclaration("var", [t.variableDeclarator(t.cloneNode(id), declaration.node)]);
    const updatedExportDeclaration = t.exportNamedDeclaration(null, [t.exportSpecifier(t.cloneNode(id), t.identifier("default"))]);
    exportDeclaration.insertAfter(updatedExportDeclaration);
    exportDeclaration.replaceWith(updatedDeclaration);

    if (needBindingRegistration) {
      scope.registerDeclaration(exportDeclaration);
    }

    return exportDeclaration;
  }

  if (exportDeclaration.get("specifiers").length > 0) {
    throw new Error("It doesn't make sense to split exported specifiers.");
  }

  const bindingIdentifiers = declaration.getOuterBindingIdentifiers();
  const specifiers = Object.keys(bindingIdentifiers).map(name => {
    return t.exportSpecifier(t.identifier(name), t.identifier(name));
  });
  const aliasDeclar = t.exportNamedDeclaration(null, specifiers);
  exportDeclaration.insertAfter(aliasDeclar);
  exportDeclaration.replaceWith(declaration.node);
  return exportDeclaration;
}