tpack-uglify-js/index.js

TPack 插件：使用 UglifyJS 压缩或格式化 JS。

/*
 * Copyright (C) 2016 xuld<xuld@vip.qq.com>
 *
 * Permission is hereby granted, free of charge, to any person 
 * obtaining a copy of this software and associated documentation 
 * files (the "Software"), to deal in the Software without restriction, 
 * including without limitation the rights to use, copy, modify, merge, 
 * publish, distribute, sublicense, and/or sell copies of the Software, 
 * and to permit persons to whom the Software is furnished to do so, 
 * subject to the following conditions:
 *　
 * The above copyright notice and this permission notice shall be 
 * included in all copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. 
 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY 
 * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, 
 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE 
 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 
 *
 */

var UglifyJS = require("uglify-js");

/**
 * 压缩或格式化 JS。
 * @param {BuildFile} file 要生成的文件。
 * @param {Object} options 相关的选项。
 * @see https://github.com/mishoo/UglifyJS
 */
module.exports = function uglifyJS(file, options) {

    // 设置默认值。
    options = Object.assign({
        inSourceMap: file.sourceMapData,
        outSourceMap: !!file.sourceMap
    }, options);

    if (options.parse !== false) {
        options.parse = Object.assign({
            filename: file.srcPath
        }, options.parse);
    }

    if (options.compress !== false) {
        options.compress = Object.assign({
            drop_console: true,
            dead_code: true,
            drop_debugger: true,
            global_defs: {
                DEBUG: false,
                RELEASE: true
            }
        }, options.compress);
    }

    if (options.output !== false) {
        options.output = Object.assign({
            comments: /^!|@preserve|@license|@cc_on/
        }, options.output);
    }

    options.fromString = true;

    // 设置警告函数。
    var oldWarnFunction;
    if (options.warnings || options.compress.warnings) {
        oldWarnFunction = UglifyJS.AST_Node.warn_function;
        UglifyJS.AST_Node.warn_function = function (text) {
            var pos = /\s*\[\d+:(\d+),(\d+)\]$/.exec(text);
            if (pos) {
                file.warning("UglifyJsWarning", null, text.substr(0, pos.index), null, +pos[1], +pos[2]);
            } else {
                file.warning("UglifyJsWarning", null, text);
            }
        };
    }

    // 生成。
    var result;
    try {
        result = UglifyJS.minify(file.content, options);
    } catch (e) {
        // 可用的字段：e.message, e.stack, e.line, e.col, e.pos
        e.name = e.constructor.name === "JS_Parse_Error" ? "UglifyJsSyntaxError" : e.name || "UglifyJsError";
        file.error(e);
        return;
    } finally {
        if (oldWarnFunction) {
            UglifyJS.AST_Node.warn_function = oldWarnFunction;
        }
    }

    // 保存。
    file.content = result.code;
    if (result.map) {
        var map = JSON.parse(result.map);
        map.sources[0] = file.srcPath;
        file.sourceMap = map;
    }
};