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- /***********************************************************************
-
- A JavaScript tokenizer / parser / beautifier / compressor.
- https://github.com/mishoo/UglifyJS2
-
- -------------------------------- (C) ---------------------------------
-
- Author: Mihai Bazon
- <mihai.bazon@gmail.com>
- http://mihai.bazon.net/blog
-
- Distributed under the BSD license:
-
- Copyright 2012 (c) Mihai Bazon <mihai.bazon@gmail.com>
-
- Redistribution and use in source and binary forms, with or without
- modification, are permitted provided that the following conditions
- are met:
-
- * Redistributions of source code must retain the above
- copyright notice, this list of conditions and the following
- disclaimer.
-
- * Redistributions in binary form must reproduce the above
- copyright notice, this list of conditions and the following
- disclaimer in the documentation and/or other materials
- provided with the distribution.
-
- THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER “AS IS” AND ANY
- EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
- PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER BE
- LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
- OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
- PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
- PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
- TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
- THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- SUCH DAMAGE.
-
- ***********************************************************************/
-
- "use strict";
-
- function find_builtins(reserved) {
- // NaN will be included due to Number.NaN
- [
- "null",
- "true",
- "false",
- "Infinity",
- "-Infinity",
- "undefined",
- ].forEach(add);
- [
- Array,
- Boolean,
- Date,
- Error,
- Function,
- Math,
- Number,
- Object,
- RegExp,
- String,
- ].forEach(function(ctor) {
- Object.getOwnPropertyNames(ctor).map(add);
- if (ctor.prototype) {
- Object.getOwnPropertyNames(ctor.prototype).map(add);
- }
- });
-
- function add(name) {
- push_uniq(reserved, name);
- }
- }
-
- function reserve_quoted_keys(ast, reserved) {
- ast.walk(new TreeWalker(function(node) {
- if (node instanceof AST_ObjectKeyVal && node.quote) {
- add(node.key);
- } else if (node instanceof AST_Sub) {
- addStrings(node.property, add);
- }
- }));
-
- function add(name) {
- push_uniq(reserved, name);
- }
- }
-
- function addStrings(node, add) {
- node.walk(new TreeWalker(function(node) {
- if (node instanceof AST_Sequence) {
- addStrings(node.tail_node(), add);
- } else if (node instanceof AST_String) {
- add(node.value);
- } else if (node instanceof AST_Conditional) {
- addStrings(node.consequent, add);
- addStrings(node.alternative, add);
- }
- return true;
- }));
- }
-
- function mangle_properties(ast, options) {
- options = defaults(options, {
- builtins: false,
- cache: null,
- debug: false,
- keep_quoted: false,
- only_cache: false,
- regex: null,
- reserved: null,
- }, true);
-
- var reserved = options.reserved;
- if (!Array.isArray(reserved)) reserved = [];
- if (!options.builtins) find_builtins(reserved);
-
- var cname = -1;
- var cache;
- if (options.cache) {
- cache = options.cache.props;
- cache.each(function(mangled_name) {
- push_uniq(reserved, mangled_name);
- });
- } else {
- cache = new Dictionary();
- }
-
- var regex = options.regex;
-
- // note debug is either false (disabled), or a string of the debug suffix to use (enabled).
- // note debug may be enabled as an empty string, which is falsey. Also treat passing 'true'
- // the same as passing an empty string.
- var debug = options.debug !== false;
- var debug_suffix;
- if (debug) debug_suffix = options.debug === true ? "" : options.debug;
-
- var names_to_mangle = [];
- var unmangleable = [];
-
- // step 1: find candidates to mangle
- ast.walk(new TreeWalker(function(node) {
- if (node instanceof AST_ObjectKeyVal) {
- add(node.key);
- } else if (node instanceof AST_ObjectProperty) {
- // setter or getter, since KeyVal is handled above
- add(node.key.name);
- } else if (node instanceof AST_Dot) {
- add(node.property);
- } else if (node instanceof AST_Sub) {
- addStrings(node.property, add);
- } else if (node instanceof AST_Call
- && node.expression.print_to_string() == "Object.defineProperty") {
- addStrings(node.args[1], add);
- }
- }));
-
- // step 2: transform the tree, renaming properties
- return ast.transform(new TreeTransformer(function(node) {
- if (node instanceof AST_ObjectKeyVal) {
- node.key = mangle(node.key);
- } else if (node instanceof AST_ObjectProperty) {
- // setter or getter
- node.key.name = mangle(node.key.name);
- } else if (node instanceof AST_Dot) {
- node.property = mangle(node.property);
- } else if (!options.keep_quoted && node instanceof AST_Sub) {
- node.property = mangleStrings(node.property);
- } else if (node instanceof AST_Call
- && node.expression.print_to_string() == "Object.defineProperty") {
- node.args[1] = mangleStrings(node.args[1]);
- }
- }));
-
- // only function declarations after this line
-
- function can_mangle(name) {
- if (unmangleable.indexOf(name) >= 0) return false;
- if (reserved.indexOf(name) >= 0) return false;
- if (options.only_cache) return cache.has(name);
- if (/^-?[0-9]+(\.[0-9]+)?(e[+-][0-9]+)?$/.test(name)) return false;
- return true;
- }
-
- function should_mangle(name) {
- if (regex && !regex.test(name)) return false;
- if (reserved.indexOf(name) >= 0) return false;
- return cache.has(name) || names_to_mangle.indexOf(name) >= 0;
- }
-
- function add(name) {
- if (can_mangle(name)) push_uniq(names_to_mangle, name);
- if (!should_mangle(name)) push_uniq(unmangleable, name);
- }
-
- function mangle(name) {
- if (!should_mangle(name)) {
- return name;
- }
- var mangled = cache.get(name);
- if (!mangled) {
- if (debug) {
- // debug mode: use a prefix and suffix to preserve readability, e.g. o.foo -> o._$foo$NNN_.
- var debug_mangled = "_$" + name + "$" + debug_suffix + "_";
- if (can_mangle(debug_mangled)) mangled = debug_mangled;
- }
- // either debug mode is off, or it is on and we could not use the mangled name
- if (!mangled) do {
- mangled = base54(++cname);
- } while (!can_mangle(mangled));
- cache.set(name, mangled);
- }
- return mangled;
- }
-
- function mangleStrings(node) {
- return node.transform(new TreeTransformer(function(node) {
- if (node instanceof AST_Sequence) {
- var last = node.expressions.length - 1;
- node.expressions[last] = mangleStrings(node.expressions[last]);
- } else if (node instanceof AST_String) {
- node.value = mangle(node.value);
- } else if (node instanceof AST_Conditional) {
- node.consequent = mangleStrings(node.consequent);
- node.alternative = mangleStrings(node.alternative);
- }
- return node;
- }));
- }
- }
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