UglifyJS/test/mozilla-ast.js

// Testing UglifyJS <-> SpiderMonkey AST conversion
"use strict";

var acorn = require("acorn");
var ufuzz = require("./ufuzz");
var UglifyJS = require("..");

function try_beautify(code) {
    var beautified = UglifyJS.minify(code, {
        compress: false,
        mangle: false,
        output: {
            beautify: true,
            braces: true,
        }
    });
    if (beautified.error) {
        console.log("// !!! beautify failed !!!");
        console.log(beautified.error.stack);
        console.log(code);
    } else {
        console.log("// (beautified)");
        console.log(beautified.code);
    }
}

function validate(ast) {
    try {
        ast.walk(new UglifyJS.TreeWalker(function(node) {
            node.validate();
        }));
    } catch (e) {
        return { error: e };
    }
    return UglifyJS.minify(ast, {
        compress: false,
        mangle: false,
        validate: true,
    });
}

function fuzzy(code) {
    return code.replace(/\bimport\s*\{\s*\}\s*from\s*(['"])/g, "import$1")
        .replace(/\b(import\b.*?)\s*,\s*\{\s*\}\s*(from\s*['"])/g, "$1 $2");
}

function test(original, estree, description) {
    var transformed = validate(UglifyJS.AST_Node.from_mozilla_ast(estree));
    if (transformed.error || original !== transformed.code && fuzzy(original) !== fuzzy(transformed.code)) {
        console.log("//=============================================================");
        console.log("// !!!!!! Failed... round", round);
        console.log("// original code");
        try_beautify(original);
        console.log();
        console.log();
        console.log("//-------------------------------------------------------------");
        console.log("//", description);
        if (transformed.error) {
            console.log(transformed.error.stack);
        } else {
            try_beautify(transformed.code);
        }
        console.log("!!!!!! Failed... round", round);
        return false;
    }
    return true;
}

var num_iterations = ufuzz.num_iterations;
var minify_options = require("./ufuzz/options.json").map(JSON.stringify);
minify_options.unshift(null);
for (var round = 1; round <= num_iterations; round++) {
    process.stdout.write(round + " of " + num_iterations + "\r");
    var code = ufuzz.createTopLevelCode();
    minify_options.forEach(function(options) {
        var input = options ? UglifyJS.minify(code, JSON.parse(options)).code : code;
        var uglified = UglifyJS.minify(input, {
            compress: false,
            mangle: false,
            output: {
                ast: true,
            },
        });
        var ok = true;
        try {
            var estree = uglified.ast.to_mozilla_ast();
        } catch (e) {
            ok = false;
            console.log("//=============================================================");
            console.log("// AST_Node.to_mozilla_ast() failed... round", round);
            console.log(e);
            console.log("// original code");
            console.log(input);
        }
        if (ok) ok = test(uglified.code, estree, "AST_Node.to_mozilla_ast()");
        if (ok) try {
            ok = test(uglified.code, acorn.parse(input, {
                ecmaVersion: "latest",
                locations: true,
                sourceType: "module",
            }), "acorn.parse()");
        } catch (e) {
            if (ufuzz.verbose) {
                console.log("//=============================================================");
                console.log("// acorn parser failed... round", round);
                console.log(e);
                console.log("// original code");
                console.log(input);
            }
        }
        if (!ok) process.exit(1);
    });
}
console.log();