parse 解釋
compress 壓縮
mangle 混淆
beautify 美化
minify 最小化
CLI 命令行工具
sourcemap 編譯后代碼對(duì)源碼的映射，用于網(wǎng)頁(yè)調(diào)試
AST 抽象語(yǔ)法樹(shù)
name 名字，包括變量名、函數(shù)名、屬性名
toplevel 頂層作用域
unreachable 不可達(dá)代碼
option 選項(xiàng)/配置
STDIN 標(biāo)準(zhǔn)輸入，指在命令行中直接輸入
STDOUT 標(biāo)準(zhǔn)

npm install uglify-js -g

npm install uglify-js

 uglifyjs [input files] [options]

 uglifyjs --compress --mangle -- input.js

 -h, --help 列出使用指南。
 `--help options` 獲取可用選項(xiàng)的詳情。
 -V, --version 打印版本號(hào)。
 -p, --parse <options> 指定解析器配置選項(xiàng):
 `acorn` 使用 Acorn 來(lái)解析。
 `bare_returns` 允許在函數(shù)外return。
 在壓縮CommonJS模塊或`.user.js `引擎調(diào)用被同步執(zhí)行函數(shù)包裹的用戶腳本 時(shí)會(huì)用到。
 `expression` 不是解析文件，二是解析一段表達(dá)式 (例如解析JSON).
 `spidermonkey` 輸入文件是 SpiderMonkey
 AST 格式 (JSON).
 -c, --compress [options] 啟用壓縮（true/false）/指定壓縮配置:
 `pure_funcs` 傳一個(gè)函數(shù)名的列表，當(dāng)這些函數(shù)返回值沒(méi)被利用時(shí)，該函數(shù)會(huì)被安全移除。
 -m, --mangle [options] 啟用混淆（true/false）/指定混淆配置:
 `reserved` 不被混淆的名字列表。
 --mangle-props [options] 混淆屬性/指定壓縮配置:
 `builtins` 混淆那些與標(biāo)準(zhǔn)JS全局變量重復(fù)的名字。
 `debug` 添加debug前綴和后綴。
 `domprops` 混淆那些魚DOM屬性名重復(fù)的名字。
 `keep_quoted` 只混淆沒(méi)括起來(lái)的屬性名。
 
 `regex` 只混淆匹配（該正則）的名字。
 `reserved` 不需要混淆的名字的列表（即保留）。
 -b, --beautify [options] 是否美化

 uglifyjs js/file1.js js/file2.js \
 -o foo.min.js -c -m \
 --source-map root="http://foo.com/src",url=foo.min.js.map

 uglifyjs ... -m reserved=[$,require,exports]'

// example.js
var x = {
 baz_: 0,
 foo_: 1,
 calc: function() {
 return this.foo_ + this.baz_;
 }
};
x.bar_ = 2;
x["baz_"] = 3;
console.log(x.calc());

$ uglifyjs example.js -c -m --mangle-props

var x={o:0,_:1,l:function(){return this._+this.o}};x.t=2,x.o=3,console.log(x.l());

$ uglifyjs example.js -c -m --mangle-props reserved=[foo_,bar_]

var x={o:0,foo_:1,_:function(){return this.foo_+this.o}};x.bar_=2,x.o=3,console.log(x._());

$ uglifyjs example.js -c -m --mangle-props regex=/_$/

var x={o:0,_:1,calc:function(){return this._+this.o}};x.l=2,x.o=3,console.log(x.calc());

$ uglifyjs example.js -c -m --mangle-props regex=/_$/,reserved=[bar_]

var x={o:0,_:1,calc:function(){return this._+this.o}};x.bar_=2,x.o=3,console.log(x.calc());

$ rm -f /tmp/cache.json # start fresh
$ uglifyjs file1.js file2.js --mangle-props --name-cache /tmp/cache.json -o part1.js
$ uglifyjs file3.js file4.js --mangle-props --name-cache /tmp/cache.json -o part2.js

// stuff.js
var o = {
 "foo": 1,
 bar: 3
};
o.foo += o.bar;
console.log(o.foo);

$ uglifyjs stuff.js --mangle-props keep_quoted -c -m

var o={foo:1,o:3};o.foo+=o.o,console.log(o.foo);

$ uglifyjs stuff.js --mangle-props debug -c -m

var o={_$foo$_:1,_$bar$_:3};o._$foo$_+=o._$bar$_,console.log(o._$foo$_);

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

var code = "function add(first, second) { return first + second; }";
var result = UglifyJS.minify(code);
console.log(result.error); // runtime error, or `undefined` if no error
console.log(result.code); // minified output: function add(n,d){return n+d}

var code = {
 "file1.js": "function add(first, second) { return first + second; }",
 "file2.js": "console.log(add(1 + 2, 3 + 4));"
};
var result = UglifyJS.minify(code);
console.log(result.code);
// function add(d,n){return d+n}console.log(add(3,7));

var code = {
 "file1.js": "function add(first, second) { return first + second; }",
 "file2.js": "console.log(add(1 + 2, 3 + 4));"
};
var options = { toplevel: true };
var result = UglifyJS.minify(code, options);
console.log(result.code);
// console.log(3+7);

var options = {
 mangle: {
 toplevel: true,
 },
 nameCache: {}
};
var result1 = UglifyJS.minify({
 "file1.js": "function add(first, second) { return first + second; }"
}, options);
var result2 = UglifyJS.minify({
 "file2.js": "console.log(add(1 + 2, 3 + 4));"
}, options);
console.log(result1.code);
// function n(n,r){return n+r}
console.log(result2.code);
// console.log(n(3,7));

var cacheFileName = "/tmp/cache.json";
var options = {
 mangle: {
 properties: true,
 },
 nameCache: JSON.parse(fs.readFileSync(cacheFileName, "utf8"))
};
fs.writeFileSync("part1.js", UglifyJS.minify({
 "file1.js": fs.readFileSync("file1.js", "utf8"),
 "file2.js": fs.readFileSync("file2.js", "utf8")
}, options).code, "utf8");
fs.writeFileSync("part2.js", UglifyJS.minify({
 "file3.js": fs.readFileSync("file3.js", "utf8"),
 "file4.js": fs.readFileSync("file4.js", "utf8")
}, options).code, "utf8");
fs.writeFileSync(cacheFileName, JSON.stringify(options.nameCache), "utf8");

var code = {
 "file1.js": "function add(first, second) { return first + second; }",
 "file2.js": "console.log(add(1 + 2, 3 + 4));"
};
var options = {
 toplevel: true,
 compress: {
 global_defs: {
 "@console.log": "alert"
 },
 passes: 2
 },
 output: {
 beautify: false,
 preamble: "/* uglified */"
 }
};
var result = UglifyJS.minify(code, options);
console.log(result.code);
// /* uglified */
// alert(10);"

var code = "function f(){ var u; return 2 + 3; }";
var options = { warnings: true };
var result = UglifyJS.minify(code, options);
console.log(result.error); // runtime error, `undefined` in this case
console.log(result.warnings); // [ 'Dropping unused variable u [0:1,18]' ]
console.log(result.code); // function f(){return 5}

var result = UglifyJS.minify({"foo.js" : "if (0) else console.log(1);"});
console.log(JSON.stringify(result.error));
// {"message":"Unexpected token: keyword (else)","filename":"foo.js","line":1,"col":7,"pos":7}

var result = UglifyJS.minify(code, options);
if (result.error) throw result.error;

{
 warnings: false,
 parse: {
 // parse options
 },
 compress: {
 // compress options
 },
 mangle: {
 // mangle options

 properties: {
 // mangle property options
 }
 },
 output: {
 // output options
 },
 sourceMap: {
 // source map options
 },
 nameCache: null, // or specify a name cache object
 toplevel: false,
 ie8: false,
}

var result = UglifyJS.minify({"file1.js": "var a = function() {};"}, {
 sourceMap: {
 filename: "out.js",
 url: "out.js.map"
 }
});
console.log(result.code); // minified output
console.log(result.map); // source map

var result = UglifyJS.minify({"file1.js": "var a = function() {};"}, {
 sourceMap: {
 root: "http://example.com/src",
 url: "out.js.map"
 }
});

var result = UglifyJS.minify({"compiled.js": "compiled code"}, {
 sourceMap: {
 content: "content from compiled.js.map",
 url: "minified.js.map"
 }
});
// same as before, it returns `code` and `map`

// test.js
var globalVar;
function funcName(firstLongName, anotherLongName) {
 var myVariable = firstLongName + anotherLongName;
}

var code = fs.readFileSync("test.js", "utf8");

UglifyJS.minify(code).code;
// 'function funcName(a,n){}var globalVar;'

UglifyJS.minify(code, { mangle: { reserved: ['firstLongName'] } }).code;
// 'function funcName(firstLongName,a){}var globalVar;'

UglifyJS.minify(code, { mangle: { toplevel: true } }).code;
// 'function n(n,a){}var a;'

function f() {
 /** @preserve Foo Bar */
 function g() {
 // this function is never called
 }
 return something();
}

if (DEBUG) {
 console.log("debug stuff");
}

const DEBUG = false;
const PRODUCTION = true;
// 等等

 uglifyjs build/defines.js js/foo.js js/bar.js... -c

var result = UglifyJS.minify(fs.readFileSync("input.js", "utf8"), {
 compress: {
 dead_code: true,
 global_defs: {
 DEBUG: false
 }
 }
});

UglifyJS.minify("alert('hello');", {
 compress: {
 global_defs: {
 "@alert": "console.log"
 }
 }
}).code;
// returns: 'console.log("hello");'

UglifyJS.minify("alert('hello');", {
 compress: {
 global_defs: {
 "alert": "console.log"
 }
 }
}).code;
// returns: '"console.log"("hello");'

// 例子: 只解析代碼，獲得原生Uglify AST

var result = UglifyJS.minify(code, {
 parse: {},
 compress: false,
 mangle: false,
 output: {
 ast: true,
 code: false // optional - faster if false
 }
});

// result.ast 即是原生 Uglify AST

// 例子: 輸入原生 Uglify AST，接著把它壓縮并混淆，生成代碼和原生ast

var result = UglifyJS.minify(ast, {
 compress: {},
 mangle: {},
 output: {
 ast: true,
 code: true // 可選，false更快
 }
});

// result.ast 是原生 Uglify AST
// result.code 是字符串格式的最小化后的代碼

 acorn file.js | uglifyjs --spidermonkey -m -c

uglifyjs file.js -m

UglifyJS.minify(code, { compress: false, mangle: true });