parcel-bundler/lib/transforms/terser.js

Blazing fast, zero configuration web application bundler

"use strict";

var _interopRequireDefault = require("@babel/runtime/helpers/interopRequireDefault");

var _asyncToGenerator2 = _interopRequireDefault(require("@babel/runtime/helpers/asyncToGenerator"));

const _require = require('terser'),
      minify = _require.minify;

const SourceMap = require('../SourceMap');

module.exports = /*#__PURE__*/function () {
  var _ref = (0, _asyncToGenerator2.default)(function* (asset) {
    yield asset.parseIfNeeded(); // Convert AST into JS

    let source = (yield asset.generate())[0].value;
    let customConfig = yield asset.getConfig(['.uglifyrc', '.terserrc']);
    let options = {
      warnings: true,
      safari10: true,
      mangle: {
        toplevel: !asset.options.scopeHoist
      }
    };
    let sourceMap;

    if (asset.options.sourceMaps) {
      sourceMap = new SourceMap();
      options.output = {
        source_map: {
          add(source, gen_line, gen_col, orig_line, orig_col, name) {
            sourceMap.addMapping({
              source,
              name,
              original: {
                line: orig_line,
                column: orig_col
              },
              generated: {
                line: gen_line,
                column: gen_col
              }
            });
          }

        }
      };
    }

    if (customConfig) {
      options = Object.assign(options, customConfig);
    }

    let result = minify(source, options);

    if (result.error) {
      throw result.error;
    }

    if (sourceMap) {
      if (asset.sourceMap) {
        asset.sourceMap = yield new SourceMap().extendSourceMap(asset.sourceMap, sourceMap);
      } else {
        asset.sourceMap = sourceMap;
      }
    } // babel-generator did our code generation for us, so remove the old AST


    asset.ast = null;
    asset.outputCode = result.code;
    asset.isAstDirty = false;
  });

  return function (_x) {
    return _ref.apply(this, arguments);
  };
}();