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