1067 lines
34 KiB
JavaScript
1067 lines
34 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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-------------------------------- (C) ---------------------------------
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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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Distributed under the BSD license:
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Copyright 2012 (c) Mihai Bazon <mihai.bazon@gmail.com>
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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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* 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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* 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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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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"use strict";
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import {
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defaults,
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keep_name,
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mergeSort,
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push_uniq,
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make_node,
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return_false,
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return_this,
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return_true,
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string_template,
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} from "./utils/index.js";
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import {
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AST_Arrow,
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AST_Block,
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AST_Call,
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AST_Class,
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AST_Conditional,
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AST_DefClass,
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AST_Defun,
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AST_Destructuring,
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AST_Dot,
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AST_DotHash,
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AST_Export,
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AST_For,
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AST_ForIn,
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AST_ForOf,
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AST_Function,
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AST_Import,
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AST_IterationStatement,
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AST_Label,
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AST_LabeledStatement,
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AST_LabelRef,
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AST_Lambda,
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AST_LoopControl,
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AST_NameMapping,
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AST_Node,
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AST_Scope,
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AST_Sequence,
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AST_String,
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AST_Sub,
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AST_Switch,
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AST_SwitchBranch,
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AST_Symbol,
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AST_SymbolBlockDeclaration,
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AST_SymbolCatch,
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AST_SymbolClass,
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AST_SymbolConst,
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AST_SymbolDefClass,
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AST_SymbolDefun,
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AST_SymbolExport,
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AST_SymbolFunarg,
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AST_SymbolImport,
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AST_SymbolLambda,
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AST_SymbolLet,
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AST_SymbolMethod,
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AST_SymbolRef,
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AST_SymbolVar,
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AST_Toplevel,
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AST_VarDef,
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AST_With,
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TreeWalker,
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walk,
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walk_abort
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} from "./ast.js";
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import {
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ALL_RESERVED_WORDS,
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js_error,
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} from "./parse.js";
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const MASK_EXPORT_DONT_MANGLE = 1 << 0;
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const MASK_EXPORT_WANT_MANGLE = 1 << 1;
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let function_defs = null;
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let unmangleable_names = null;
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/**
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* When defined, there is a function declaration somewhere that's inside of a block.
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* See https://tc39.es/ecma262/multipage/additional-ecmascript-features-for-web-browsers.html#sec-block-level-function-declarations-web-legacy-compatibility-semantics
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*/
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let scopes_with_block_defuns = null;
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class SymbolDef {
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constructor(scope, orig, init) {
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this.name = orig.name;
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this.orig = [ orig ];
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this.init = init;
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this.eliminated = 0;
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this.assignments = 0;
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this.scope = scope;
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this.replaced = 0;
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this.global = false;
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this.export = 0;
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this.mangled_name = null;
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this.undeclared = false;
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this.id = SymbolDef.next_id++;
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this.chained = false;
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this.direct_access = false;
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this.escaped = 0;
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this.recursive_refs = 0;
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this.references = [];
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this.should_replace = undefined;
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this.single_use = false;
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this.fixed = false;
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Object.seal(this);
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}
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fixed_value() {
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if (!this.fixed || this.fixed instanceof AST_Node) return this.fixed;
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return this.fixed();
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}
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unmangleable(options) {
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if (!options) options = {};
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if (
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function_defs &&
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function_defs.has(this.id) &&
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keep_name(options.keep_fnames, this.orig[0].name)
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) return true;
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return this.global && !options.toplevel
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|| (this.export & MASK_EXPORT_DONT_MANGLE)
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|| this.undeclared
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|| !options.eval && this.scope.pinned()
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|| (this.orig[0] instanceof AST_SymbolLambda
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|| this.orig[0] instanceof AST_SymbolDefun) && keep_name(options.keep_fnames, this.orig[0].name)
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|| this.orig[0] instanceof AST_SymbolMethod
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|| (this.orig[0] instanceof AST_SymbolClass
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|| this.orig[0] instanceof AST_SymbolDefClass) && keep_name(options.keep_classnames, this.orig[0].name);
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}
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mangle(options) {
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const cache = options.cache && options.cache.props;
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if (this.global && cache && cache.has(this.name)) {
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this.mangled_name = cache.get(this.name);
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} else if (!this.mangled_name && !this.unmangleable(options)) {
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var s = this.scope;
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var sym = this.orig[0];
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if (options.ie8 && sym instanceof AST_SymbolLambda)
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s = s.parent_scope;
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const redefinition = redefined_catch_def(this);
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this.mangled_name = redefinition
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? redefinition.mangled_name || redefinition.name
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: s.next_mangled(options, this);
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if (this.global && cache) {
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cache.set(this.name, this.mangled_name);
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}
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}
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}
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}
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SymbolDef.next_id = 1;
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function redefined_catch_def(def) {
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if (def.orig[0] instanceof AST_SymbolCatch
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&& def.scope.is_block_scope()
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) {
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return def.scope.get_defun_scope().variables.get(def.name);
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}
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}
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AST_Scope.DEFMETHOD("figure_out_scope", function(options, { parent_scope = null, toplevel = this } = {}) {
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options = defaults(options, {
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cache: null,
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ie8: false,
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safari10: false,
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module: false,
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});
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if (!(toplevel instanceof AST_Toplevel)) {
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throw new Error("Invalid toplevel scope");
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}
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// pass 1: setup scope chaining and handle definitions
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var scope = this.parent_scope = parent_scope;
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var labels = new Map();
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var defun = null;
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var in_destructuring = null;
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var for_scopes = [];
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var tw = new TreeWalker((node, descend) => {
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if (node.is_block_scope()) {
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const save_scope = scope;
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node.block_scope = scope = new AST_Scope(node);
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scope._block_scope = true;
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scope.init_scope_vars(save_scope);
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scope.uses_with = save_scope.uses_with;
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scope.uses_eval = save_scope.uses_eval;
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if (options.safari10) {
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if (node instanceof AST_For || node instanceof AST_ForIn || node instanceof AST_ForOf) {
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for_scopes.push(scope);
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}
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}
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if (node instanceof AST_Switch) {
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// XXX: HACK! Ensure the switch expression gets the correct scope (the parent scope) and the body gets the contained scope
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// AST_Switch has a scope within the body, but it itself "is a block scope"
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// This means the switched expression has to belong to the outer scope
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// while the body inside belongs to the switch itself.
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// This is pretty nasty and warrants an AST change
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const the_block_scope = scope;
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scope = save_scope;
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node.expression.walk(tw);
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scope = the_block_scope;
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for (let i = 0; i < node.body.length; i++) {
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node.body[i].walk(tw);
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}
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} else {
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descend();
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}
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scope = save_scope;
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return true;
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}
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if (node instanceof AST_Destructuring) {
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const save_destructuring = in_destructuring;
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in_destructuring = node;
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descend();
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in_destructuring = save_destructuring;
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return true;
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}
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if (node instanceof AST_Scope) {
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node.init_scope_vars(scope);
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var save_scope = scope;
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var save_defun = defun;
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var save_labels = labels;
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defun = scope = node;
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labels = new Map();
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descend();
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scope = save_scope;
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defun = save_defun;
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labels = save_labels;
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return true; // don't descend again in TreeWalker
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}
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if (node instanceof AST_LabeledStatement) {
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var l = node.label;
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if (labels.has(l.name)) {
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throw new Error(string_template("Label {name} defined twice", l));
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}
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labels.set(l.name, l);
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descend();
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labels.delete(l.name);
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return true; // no descend again
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}
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if (node instanceof AST_With) {
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for (var s = scope; s; s = s.parent_scope)
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s.uses_with = true;
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return;
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}
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if (node instanceof AST_Symbol) {
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node.scope = scope;
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}
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if (node instanceof AST_Label) {
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node.thedef = node;
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node.references = [];
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}
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if (node instanceof AST_SymbolLambda) {
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defun.def_function(node, node.name == "arguments" ? undefined : defun);
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} else if (node instanceof AST_SymbolDefun) {
|
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// Careful here, the scope where this should be defined is
|
||
|
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// the parent scope. The reason is that we enter a new
|
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|
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// scope when we encounter the AST_Defun node (which is
|
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|
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// instanceof AST_Scope) but we get to the symbol a bit
|
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|
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// later.
|
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|
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const closest_scope = defun.parent_scope;
|
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|
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|
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|
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// In strict mode, function definitions are block-scoped
|
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|
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node.scope = tw.directives["use strict"]
|
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|
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? closest_scope
|
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|
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: closest_scope.get_defun_scope();
|
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|
|
|
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|
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mark_export(node.scope.def_function(node, defun), 1);
|
||
|
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} else if (node instanceof AST_SymbolClass) {
|
||
|
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mark_export(defun.def_variable(node, defun), 1);
|
||
|
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} else if (node instanceof AST_SymbolImport) {
|
||
|
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scope.def_variable(node);
|
||
|
|
} else if (node instanceof AST_SymbolDefClass) {
|
||
|
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// This deals with the name of the class being available
|
||
|
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// inside the class.
|
||
|
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mark_export((node.scope = defun.parent_scope).def_function(node, defun), 1);
|
||
|
|
} else if (
|
||
|
|
node instanceof AST_SymbolVar
|
||
|
|
|| node instanceof AST_SymbolLet
|
||
|
|
|| node instanceof AST_SymbolConst
|
||
|
|
|| node instanceof AST_SymbolCatch
|
||
|
|
) {
|
||
|
|
var def;
|
||
|
|
if (node instanceof AST_SymbolBlockDeclaration) {
|
||
|
|
def = scope.def_variable(node, null);
|
||
|
|
} else {
|
||
|
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def = defun.def_variable(node, node.TYPE == "SymbolVar" ? null : undefined);
|
||
|
|
}
|
||
|
|
if (!def.orig.every((sym) => {
|
||
|
|
if (sym === node) return true;
|
||
|
|
if (node instanceof AST_SymbolBlockDeclaration) {
|
||
|
|
return sym instanceof AST_SymbolLambda;
|
||
|
|
}
|
||
|
|
return !(sym instanceof AST_SymbolLet || sym instanceof AST_SymbolConst);
|
||
|
|
})) {
|
||
|
|
js_error(
|
||
|
|
`"${node.name}" is redeclared`,
|
||
|
|
node.start.file,
|
||
|
|
node.start.line,
|
||
|
|
node.start.col,
|
||
|
|
node.start.pos
|
||
|
|
);
|
||
|
|
}
|
||
|
|
if (!(node instanceof AST_SymbolFunarg)) mark_export(def, 2);
|
||
|
|
if (defun !== scope) {
|
||
|
|
node.mark_enclosed();
|
||
|
|
var def = scope.find_variable(node);
|
||
|
|
if (node.thedef !== def) {
|
||
|
|
node.thedef = def;
|
||
|
|
node.reference();
|
||
|
|
}
|
||
|
|
}
|
||
|
|
} else if (node instanceof AST_LabelRef) {
|
||
|
|
var sym = labels.get(node.name);
|
||
|
|
if (!sym) throw new Error(string_template("Undefined label {name} [{line},{col}]", {
|
||
|
|
name: node.name,
|
||
|
|
line: node.start.line,
|
||
|
|
col: node.start.col
|
||
|
|
}));
|
||
|
|
node.thedef = sym;
|
||
|
|
}
|
||
|
|
if (!(scope instanceof AST_Toplevel) && (node instanceof AST_Export || node instanceof AST_Import)) {
|
||
|
|
js_error(
|
||
|
|
`"${node.TYPE}" statement may only appear at the top level`,
|
||
|
|
node.start.file,
|
||
|
|
node.start.line,
|
||
|
|
node.start.col,
|
||
|
|
node.start.pos
|
||
|
|
);
|
||
|
|
}
|
||
|
|
});
|
||
|
|
|
||
|
|
if (options.module) {
|
||
|
|
tw.directives["use strict"] = true;
|
||
|
|
}
|
||
|
|
|
||
|
|
this.walk(tw);
|
||
|
|
|
||
|
|
function mark_export(def, level) {
|
||
|
|
if (in_destructuring) {
|
||
|
|
var i = 0;
|
||
|
|
do {
|
||
|
|
level++;
|
||
|
|
} while (tw.parent(i++) !== in_destructuring);
|
||
|
|
}
|
||
|
|
var node = tw.parent(level);
|
||
|
|
if (def.export = node instanceof AST_Export ? MASK_EXPORT_DONT_MANGLE : 0) {
|
||
|
|
var exported = node.exported_definition;
|
||
|
|
if ((exported instanceof AST_Defun || exported instanceof AST_DefClass) && node.is_default) {
|
||
|
|
def.export = MASK_EXPORT_WANT_MANGLE;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
// pass 2: find back references and eval
|
||
|
|
const is_toplevel = this instanceof AST_Toplevel;
|
||
|
|
if (is_toplevel) {
|
||
|
|
this.globals = new Map();
|
||
|
|
}
|
||
|
|
|
||
|
|
var tw = new TreeWalker(node => {
|
||
|
|
if (node instanceof AST_LoopControl && node.label) {
|
||
|
|
node.label.thedef.references.push(node);
|
||
|
|
return true;
|
||
|
|
}
|
||
|
|
if (node instanceof AST_SymbolRef) {
|
||
|
|
var name = node.name;
|
||
|
|
if (name == "eval" && tw.parent() instanceof AST_Call) {
|
||
|
|
for (var s = node.scope; s && !s.uses_eval; s = s.parent_scope) {
|
||
|
|
s.uses_eval = true;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
var sym;
|
||
|
|
if (tw.parent() instanceof AST_NameMapping && tw.parent(1).module_name
|
||
|
|
|| !(sym = node.scope.find_variable(name))) {
|
||
|
|
|
||
|
|
sym = toplevel.def_global(node);
|
||
|
|
if (node instanceof AST_SymbolExport) sym.export = MASK_EXPORT_DONT_MANGLE;
|
||
|
|
} else if (sym.scope instanceof AST_Lambda && name == "arguments") {
|
||
|
|
sym.scope.get_defun_scope().uses_arguments = true;
|
||
|
|
}
|
||
|
|
node.thedef = sym;
|
||
|
|
node.reference();
|
||
|
|
if (node.scope.is_block_scope()
|
||
|
|
&& !(sym.orig[0] instanceof AST_SymbolBlockDeclaration)) {
|
||
|
|
node.scope = node.scope.get_defun_scope();
|
||
|
|
}
|
||
|
|
return true;
|
||
|
|
}
|
||
|
|
// ensure mangling works if catch reuses a scope variable
|
||
|
|
var def;
|
||
|
|
if (node instanceof AST_SymbolCatch && (def = redefined_catch_def(node.definition()))) {
|
||
|
|
var s = node.scope;
|
||
|
|
while (s) {
|
||
|
|
push_uniq(s.enclosed, def);
|
||
|
|
if (s === def.scope) break;
|
||
|
|
s = s.parent_scope;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
});
|
||
|
|
this.walk(tw);
|
||
|
|
|
||
|
|
// pass 3: work around IE8 and Safari catch scope bugs
|
||
|
|
if (options.ie8 || options.safari10) {
|
||
|
|
walk(this, node => {
|
||
|
|
if (node instanceof AST_SymbolCatch) {
|
||
|
|
var name = node.name;
|
||
|
|
var refs = node.thedef.references;
|
||
|
|
var scope = node.scope.get_defun_scope();
|
||
|
|
var def = scope.find_variable(name)
|
||
|
|
|| toplevel.globals.get(name)
|
||
|
|
|| scope.def_variable(node);
|
||
|
|
refs.forEach(function(ref) {
|
||
|
|
ref.thedef = def;
|
||
|
|
ref.reference();
|
||
|
|
});
|
||
|
|
node.thedef = def;
|
||
|
|
node.reference();
|
||
|
|
return true;
|
||
|
|
}
|
||
|
|
});
|
||
|
|
}
|
||
|
|
|
||
|
|
// pass 4: add symbol definitions to loop scopes
|
||
|
|
// Safari/Webkit bug workaround - loop init let variable shadowing argument.
|
||
|
|
// https://github.com/mishoo/UglifyJS2/issues/1753
|
||
|
|
// https://bugs.webkit.org/show_bug.cgi?id=171041
|
||
|
|
if (options.safari10) {
|
||
|
|
for (const scope of for_scopes) {
|
||
|
|
scope.parent_scope.variables.forEach(function(def) {
|
||
|
|
push_uniq(scope.enclosed, def);
|
||
|
|
});
|
||
|
|
}
|
||
|
|
}
|
||
|
|
});
|
||
|
|
|
||
|
|
AST_Toplevel.DEFMETHOD("def_global", function(node) {
|
||
|
|
var globals = this.globals, name = node.name;
|
||
|
|
if (globals.has(name)) {
|
||
|
|
return globals.get(name);
|
||
|
|
} else {
|
||
|
|
var g = new SymbolDef(this, node);
|
||
|
|
g.undeclared = true;
|
||
|
|
g.global = true;
|
||
|
|
globals.set(name, g);
|
||
|
|
return g;
|
||
|
|
}
|
||
|
|
});
|
||
|
|
|
||
|
|
AST_Scope.DEFMETHOD("init_scope_vars", function(parent_scope) {
|
||
|
|
this.variables = new Map(); // map name to AST_SymbolVar (variables defined in this scope; includes functions)
|
||
|
|
this.uses_with = false; // will be set to true if this or some nested scope uses the `with` statement
|
||
|
|
this.uses_eval = false; // will be set to true if this or nested scope uses the global `eval`
|
||
|
|
this.parent_scope = parent_scope; // the parent scope
|
||
|
|
this.enclosed = []; // a list of variables from this or outer scope(s) that are referenced from this or inner scopes
|
||
|
|
this.cname = -1; // the current index for mangling functions/variables
|
||
|
|
});
|
||
|
|
|
||
|
|
AST_Scope.DEFMETHOD("conflicting_def", function (name) {
|
||
|
|
return (
|
||
|
|
this.enclosed.find(def => def.name === name)
|
||
|
|
|| this.variables.has(name)
|
||
|
|
|| (this.parent_scope && this.parent_scope.conflicting_def(name))
|
||
|
|
);
|
||
|
|
});
|
||
|
|
|
||
|
|
AST_Scope.DEFMETHOD("conflicting_def_shallow", function (name) {
|
||
|
|
return (
|
||
|
|
this.enclosed.find(def => def.name === name)
|
||
|
|
|| this.variables.has(name)
|
||
|
|
);
|
||
|
|
});
|
||
|
|
|
||
|
|
AST_Scope.DEFMETHOD("add_child_scope", function (scope) {
|
||
|
|
// `scope` is going to be moved into `this` right now.
|
||
|
|
// Update the required scopes' information
|
||
|
|
|
||
|
|
if (scope.parent_scope === this) return;
|
||
|
|
|
||
|
|
scope.parent_scope = this;
|
||
|
|
|
||
|
|
// Propagate to this.uses_arguments from arrow functions
|
||
|
|
if ((scope instanceof AST_Arrow) && !this.uses_arguments) {
|
||
|
|
this.uses_arguments = walk(scope, node => {
|
||
|
|
if (
|
||
|
|
node instanceof AST_SymbolRef
|
||
|
|
&& node.scope instanceof AST_Lambda
|
||
|
|
&& node.name === "arguments"
|
||
|
|
) {
|
||
|
|
return walk_abort;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (node instanceof AST_Lambda && !(node instanceof AST_Arrow)) {
|
||
|
|
return true;
|
||
|
|
}
|
||
|
|
});
|
||
|
|
}
|
||
|
|
|
||
|
|
this.uses_with = this.uses_with || scope.uses_with;
|
||
|
|
this.uses_eval = this.uses_eval || scope.uses_eval;
|
||
|
|
|
||
|
|
const scope_ancestry = (() => {
|
||
|
|
const ancestry = [];
|
||
|
|
let cur = this;
|
||
|
|
do {
|
||
|
|
ancestry.push(cur);
|
||
|
|
} while ((cur = cur.parent_scope));
|
||
|
|
ancestry.reverse();
|
||
|
|
return ancestry;
|
||
|
|
})();
|
||
|
|
|
||
|
|
const new_scope_enclosed_set = new Set(scope.enclosed);
|
||
|
|
const to_enclose = [];
|
||
|
|
for (const scope_topdown of scope_ancestry) {
|
||
|
|
to_enclose.forEach(e => push_uniq(scope_topdown.enclosed, e));
|
||
|
|
for (const def of scope_topdown.variables.values()) {
|
||
|
|
if (new_scope_enclosed_set.has(def)) {
|
||
|
|
push_uniq(to_enclose, def);
|
||
|
|
push_uniq(scope_topdown.enclosed, def);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
});
|
||
|
|
|
||
|
|
function find_scopes_visible_from(scopes) {
|
||
|
|
const found_scopes = new Set();
|
||
|
|
|
||
|
|
for (const scope of new Set(scopes)) {
|
||
|
|
(function bubble_up(scope) {
|
||
|
|
if (scope == null || found_scopes.has(scope)) return;
|
||
|
|
|
||
|
|
found_scopes.add(scope);
|
||
|
|
|
||
|
|
bubble_up(scope.parent_scope);
|
||
|
|
})(scope);
|
||
|
|
}
|
||
|
|
|
||
|
|
return [...found_scopes];
|
||
|
|
}
|
||
|
|
|
||
|
|
// Creates a symbol during compression
|
||
|
|
AST_Scope.DEFMETHOD("create_symbol", function(SymClass, {
|
||
|
|
source,
|
||
|
|
tentative_name,
|
||
|
|
scope,
|
||
|
|
conflict_scopes = [scope],
|
||
|
|
init = null
|
||
|
|
} = {}) {
|
||
|
|
let symbol_name;
|
||
|
|
|
||
|
|
conflict_scopes = find_scopes_visible_from(conflict_scopes);
|
||
|
|
|
||
|
|
if (tentative_name) {
|
||
|
|
// Implement hygiene (no new names are conflicting with existing names)
|
||
|
|
tentative_name =
|
||
|
|
symbol_name =
|
||
|
|
tentative_name.replace(/(?:^[^a-z_$]|[^a-z0-9_$])/ig, "_");
|
||
|
|
|
||
|
|
let i = 0;
|
||
|
|
while (conflict_scopes.find(s => s.conflicting_def_shallow(symbol_name))) {
|
||
|
|
symbol_name = tentative_name + "$" + i++;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
if (!symbol_name) {
|
||
|
|
throw new Error("No symbol name could be generated in create_symbol()");
|
||
|
|
}
|
||
|
|
|
||
|
|
const symbol = make_node(SymClass, source, {
|
||
|
|
name: symbol_name,
|
||
|
|
scope
|
||
|
|
});
|
||
|
|
|
||
|
|
this.def_variable(symbol, init || null);
|
||
|
|
|
||
|
|
symbol.mark_enclosed();
|
||
|
|
|
||
|
|
return symbol;
|
||
|
|
});
|
||
|
|
|
||
|
|
|
||
|
|
AST_Node.DEFMETHOD("is_block_scope", return_false);
|
||
|
|
AST_Class.DEFMETHOD("is_block_scope", return_false);
|
||
|
|
AST_Lambda.DEFMETHOD("is_block_scope", return_false);
|
||
|
|
AST_Toplevel.DEFMETHOD("is_block_scope", return_false);
|
||
|
|
AST_SwitchBranch.DEFMETHOD("is_block_scope", return_false);
|
||
|
|
AST_Block.DEFMETHOD("is_block_scope", return_true);
|
||
|
|
AST_Scope.DEFMETHOD("is_block_scope", function () {
|
||
|
|
return this._block_scope || false;
|
||
|
|
});
|
||
|
|
AST_IterationStatement.DEFMETHOD("is_block_scope", return_true);
|
||
|
|
|
||
|
|
AST_Lambda.DEFMETHOD("init_scope_vars", function() {
|
||
|
|
AST_Scope.prototype.init_scope_vars.apply(this, arguments);
|
||
|
|
this.uses_arguments = false;
|
||
|
|
this.def_variable(new AST_SymbolFunarg({
|
||
|
|
name: "arguments",
|
||
|
|
start: this.start,
|
||
|
|
end: this.end
|
||
|
|
}));
|
||
|
|
});
|
||
|
|
|
||
|
|
AST_Arrow.DEFMETHOD("init_scope_vars", function() {
|
||
|
|
AST_Scope.prototype.init_scope_vars.apply(this, arguments);
|
||
|
|
this.uses_arguments = false;
|
||
|
|
});
|
||
|
|
|
||
|
|
AST_Symbol.DEFMETHOD("mark_enclosed", function() {
|
||
|
|
var def = this.definition();
|
||
|
|
var s = this.scope;
|
||
|
|
while (s) {
|
||
|
|
push_uniq(s.enclosed, def);
|
||
|
|
if (s === def.scope) break;
|
||
|
|
s = s.parent_scope;
|
||
|
|
}
|
||
|
|
});
|
||
|
|
|
||
|
|
AST_Symbol.DEFMETHOD("reference", function() {
|
||
|
|
this.definition().references.push(this);
|
||
|
|
this.mark_enclosed();
|
||
|
|
});
|
||
|
|
|
||
|
|
AST_Scope.DEFMETHOD("find_variable", function(name) {
|
||
|
|
if (name instanceof AST_Symbol) name = name.name;
|
||
|
|
return this.variables.get(name)
|
||
|
|
|| (this.parent_scope && this.parent_scope.find_variable(name));
|
||
|
|
});
|
||
|
|
|
||
|
|
AST_Scope.DEFMETHOD("def_function", function(symbol, init) {
|
||
|
|
var def = this.def_variable(symbol, init);
|
||
|
|
if (!def.init || def.init instanceof AST_Defun) def.init = init;
|
||
|
|
return def;
|
||
|
|
});
|
||
|
|
|
||
|
|
AST_Scope.DEFMETHOD("def_variable", function(symbol, init) {
|
||
|
|
var def = this.variables.get(symbol.name);
|
||
|
|
if (def) {
|
||
|
|
def.orig.push(symbol);
|
||
|
|
if (def.init && (def.scope !== symbol.scope || def.init instanceof AST_Function)) {
|
||
|
|
def.init = init;
|
||
|
|
}
|
||
|
|
} else {
|
||
|
|
def = new SymbolDef(this, symbol, init);
|
||
|
|
this.variables.set(symbol.name, def);
|
||
|
|
def.global = !this.parent_scope;
|
||
|
|
}
|
||
|
|
return symbol.thedef = def;
|
||
|
|
});
|
||
|
|
|
||
|
|
function next_mangled(scope, options) {
|
||
|
|
let defun_scope;
|
||
|
|
if (
|
||
|
|
scopes_with_block_defuns
|
||
|
|
&& (defun_scope = scope.get_defun_scope())
|
||
|
|
&& scopes_with_block_defuns.has(defun_scope)
|
||
|
|
) {
|
||
|
|
scope = defun_scope;
|
||
|
|
}
|
||
|
|
|
||
|
|
var ext = scope.enclosed;
|
||
|
|
var nth_identifier = options.nth_identifier;
|
||
|
|
out: while (true) {
|
||
|
|
var m = nth_identifier.get(++scope.cname);
|
||
|
|
if (ALL_RESERVED_WORDS.has(m)) continue; // skip over "do"
|
||
|
|
|
||
|
|
// https://github.com/mishoo/UglifyJS2/issues/242 -- do not
|
||
|
|
// shadow a name reserved from mangling.
|
||
|
|
if (options.reserved.has(m)) continue;
|
||
|
|
|
||
|
|
// Functions with short names might collide with base54 output
|
||
|
|
// and therefore cause collisions when keep_fnames is true.
|
||
|
|
if (unmangleable_names && unmangleable_names.has(m)) continue out;
|
||
|
|
|
||
|
|
// we must ensure that the mangled name does not shadow a name
|
||
|
|
// from some parent scope that is referenced in this or in
|
||
|
|
// inner scopes.
|
||
|
|
for (let i = ext.length; --i >= 0;) {
|
||
|
|
const def = ext[i];
|
||
|
|
const name = def.mangled_name || (def.unmangleable(options) && def.name);
|
||
|
|
if (m == name) continue out;
|
||
|
|
}
|
||
|
|
return m;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
AST_Scope.DEFMETHOD("next_mangled", function(options) {
|
||
|
|
return next_mangled(this, options);
|
||
|
|
});
|
||
|
|
|
||
|
|
AST_Toplevel.DEFMETHOD("next_mangled", function(options) {
|
||
|
|
let name;
|
||
|
|
const mangled_names = this.mangled_names;
|
||
|
|
do {
|
||
|
|
name = next_mangled(this, options);
|
||
|
|
} while (mangled_names.has(name));
|
||
|
|
return name;
|
||
|
|
});
|
||
|
|
|
||
|
|
AST_Function.DEFMETHOD("next_mangled", function(options, def) {
|
||
|
|
// #179, #326
|
||
|
|
// in Safari strict mode, something like (function x(x){...}) is a syntax error;
|
||
|
|
// a function expression's argument cannot shadow the function expression's name
|
||
|
|
|
||
|
|
var tricky_def = def.orig[0] instanceof AST_SymbolFunarg && this.name && this.name.definition();
|
||
|
|
|
||
|
|
// the function's mangled_name is null when keep_fnames is true
|
||
|
|
var tricky_name = tricky_def ? tricky_def.mangled_name || tricky_def.name : null;
|
||
|
|
|
||
|
|
while (true) {
|
||
|
|
var name = next_mangled(this, options);
|
||
|
|
if (!tricky_name || tricky_name != name)
|
||
|
|
return name;
|
||
|
|
}
|
||
|
|
});
|
||
|
|
|
||
|
|
AST_Symbol.DEFMETHOD("unmangleable", function(options) {
|
||
|
|
var def = this.definition();
|
||
|
|
return !def || def.unmangleable(options);
|
||
|
|
});
|
||
|
|
|
||
|
|
// labels are always mangleable
|
||
|
|
AST_Label.DEFMETHOD("unmangleable", return_false);
|
||
|
|
|
||
|
|
AST_Symbol.DEFMETHOD("unreferenced", function() {
|
||
|
|
return !this.definition().references.length && !this.scope.pinned();
|
||
|
|
});
|
||
|
|
|
||
|
|
AST_Symbol.DEFMETHOD("definition", function() {
|
||
|
|
return this.thedef;
|
||
|
|
});
|
||
|
|
|
||
|
|
AST_Symbol.DEFMETHOD("global", function() {
|
||
|
|
return this.thedef.global;
|
||
|
|
});
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Format the mangler options (if any) into their appropriate types
|
||
|
|
*/
|
||
|
|
export function format_mangler_options(options) {
|
||
|
|
options = defaults(options, {
|
||
|
|
eval : false,
|
||
|
|
nth_identifier : base54,
|
||
|
|
ie8 : false,
|
||
|
|
keep_classnames: false,
|
||
|
|
keep_fnames : false,
|
||
|
|
module : false,
|
||
|
|
reserved : [],
|
||
|
|
toplevel : false,
|
||
|
|
});
|
||
|
|
if (options.module) options.toplevel = true;
|
||
|
|
if (!Array.isArray(options.reserved)
|
||
|
|
&& !(options.reserved instanceof Set)
|
||
|
|
) {
|
||
|
|
options.reserved = [];
|
||
|
|
}
|
||
|
|
options.reserved = new Set(options.reserved);
|
||
|
|
// Never mangle arguments
|
||
|
|
options.reserved.add("arguments");
|
||
|
|
return options;
|
||
|
|
}
|
||
|
|
|
||
|
|
AST_Toplevel.DEFMETHOD("mangle_names", function(options) {
|
||
|
|
options = format_mangler_options(options);
|
||
|
|
var nth_identifier = options.nth_identifier;
|
||
|
|
|
||
|
|
// We only need to mangle declaration nodes. Special logic wired
|
||
|
|
// into the code generator will display the mangled name if it's
|
||
|
|
// present (and for AST_SymbolRef-s it'll use the mangled name of
|
||
|
|
// the AST_SymbolDeclaration that it points to).
|
||
|
|
var lname = -1;
|
||
|
|
var to_mangle = [];
|
||
|
|
|
||
|
|
if (options.keep_fnames) {
|
||
|
|
function_defs = new Set();
|
||
|
|
}
|
||
|
|
|
||
|
|
const mangled_names = this.mangled_names = new Set();
|
||
|
|
unmangleable_names = new Set();
|
||
|
|
|
||
|
|
if (options.cache) {
|
||
|
|
this.globals.forEach(collect);
|
||
|
|
if (options.cache.props) {
|
||
|
|
options.cache.props.forEach(function(mangled_name) {
|
||
|
|
mangled_names.add(mangled_name);
|
||
|
|
});
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
var tw = new TreeWalker(function(node, descend) {
|
||
|
|
if (node instanceof AST_LabeledStatement) {
|
||
|
|
// lname is incremented when we get to the AST_Label
|
||
|
|
var save_nesting = lname;
|
||
|
|
descend();
|
||
|
|
lname = save_nesting;
|
||
|
|
return true; // don't descend again in TreeWalker
|
||
|
|
}
|
||
|
|
if (
|
||
|
|
node instanceof AST_Defun
|
||
|
|
&& !(tw.parent() instanceof AST_Scope)
|
||
|
|
) {
|
||
|
|
scopes_with_block_defuns = scopes_with_block_defuns || new Set();
|
||
|
|
scopes_with_block_defuns.add(node.parent_scope.get_defun_scope());
|
||
|
|
}
|
||
|
|
if (node instanceof AST_Scope) {
|
||
|
|
node.variables.forEach(collect);
|
||
|
|
return;
|
||
|
|
}
|
||
|
|
if (node.is_block_scope()) {
|
||
|
|
node.block_scope.variables.forEach(collect);
|
||
|
|
return;
|
||
|
|
}
|
||
|
|
if (
|
||
|
|
function_defs
|
||
|
|
&& node instanceof AST_VarDef
|
||
|
|
&& node.value instanceof AST_Lambda
|
||
|
|
&& !node.value.name
|
||
|
|
&& keep_name(options.keep_fnames, node.name.name)
|
||
|
|
) {
|
||
|
|
function_defs.add(node.name.definition().id);
|
||
|
|
return;
|
||
|
|
}
|
||
|
|
if (node instanceof AST_Label) {
|
||
|
|
let name;
|
||
|
|
do {
|
||
|
|
name = nth_identifier.get(++lname);
|
||
|
|
} while (ALL_RESERVED_WORDS.has(name));
|
||
|
|
node.mangled_name = name;
|
||
|
|
return true;
|
||
|
|
}
|
||
|
|
if (!(options.ie8 || options.safari10) && node instanceof AST_SymbolCatch) {
|
||
|
|
to_mangle.push(node.definition());
|
||
|
|
return;
|
||
|
|
}
|
||
|
|
});
|
||
|
|
|
||
|
|
this.walk(tw);
|
||
|
|
|
||
|
|
if (options.keep_fnames || options.keep_classnames) {
|
||
|
|
// Collect a set of short names which are unmangleable,
|
||
|
|
// for use in avoiding collisions in next_mangled.
|
||
|
|
to_mangle.forEach(def => {
|
||
|
|
if (def.name.length < 6 && def.unmangleable(options)) {
|
||
|
|
unmangleable_names.add(def.name);
|
||
|
|
}
|
||
|
|
});
|
||
|
|
}
|
||
|
|
|
||
|
|
to_mangle.forEach(def => { def.mangle(options); });
|
||
|
|
|
||
|
|
function_defs = null;
|
||
|
|
unmangleable_names = null;
|
||
|
|
scopes_with_block_defuns = null;
|
||
|
|
|
||
|
|
function collect(symbol) {
|
||
|
|
if (symbol.export & MASK_EXPORT_DONT_MANGLE) {
|
||
|
|
unmangleable_names.add(symbol.name);
|
||
|
|
} else if (!options.reserved.has(symbol.name)) {
|
||
|
|
to_mangle.push(symbol);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
});
|
||
|
|
|
||
|
|
AST_Toplevel.DEFMETHOD("find_colliding_names", function(options) {
|
||
|
|
const cache = options.cache && options.cache.props;
|
||
|
|
const avoid = new Set();
|
||
|
|
options.reserved.forEach(to_avoid);
|
||
|
|
this.globals.forEach(add_def);
|
||
|
|
this.walk(new TreeWalker(function(node) {
|
||
|
|
if (node instanceof AST_Scope) node.variables.forEach(add_def);
|
||
|
|
if (node instanceof AST_SymbolCatch) add_def(node.definition());
|
||
|
|
}));
|
||
|
|
return avoid;
|
||
|
|
|
||
|
|
function to_avoid(name) {
|
||
|
|
avoid.add(name);
|
||
|
|
}
|
||
|
|
|
||
|
|
function add_def(def) {
|
||
|
|
var name = def.name;
|
||
|
|
if (def.global && cache && cache.has(name)) name = cache.get(name);
|
||
|
|
else if (!def.unmangleable(options)) return;
|
||
|
|
to_avoid(name);
|
||
|
|
}
|
||
|
|
});
|
||
|
|
|
||
|
|
AST_Toplevel.DEFMETHOD("expand_names", function(options) {
|
||
|
|
options = format_mangler_options(options);
|
||
|
|
var nth_identifier = options.nth_identifier;
|
||
|
|
if (nth_identifier.reset && nth_identifier.sort) {
|
||
|
|
nth_identifier.reset();
|
||
|
|
nth_identifier.sort();
|
||
|
|
}
|
||
|
|
var avoid = this.find_colliding_names(options);
|
||
|
|
var cname = 0;
|
||
|
|
this.globals.forEach(rename);
|
||
|
|
this.walk(new TreeWalker(function(node) {
|
||
|
|
if (node instanceof AST_Scope) node.variables.forEach(rename);
|
||
|
|
if (node instanceof AST_SymbolCatch) rename(node.definition());
|
||
|
|
}));
|
||
|
|
|
||
|
|
function next_name() {
|
||
|
|
var name;
|
||
|
|
do {
|
||
|
|
name = nth_identifier.get(cname++);
|
||
|
|
} while (avoid.has(name) || ALL_RESERVED_WORDS.has(name));
|
||
|
|
return name;
|
||
|
|
}
|
||
|
|
|
||
|
|
function rename(def) {
|
||
|
|
if (def.global && options.cache) return;
|
||
|
|
if (def.unmangleable(options)) return;
|
||
|
|
if (options.reserved.has(def.name)) return;
|
||
|
|
const redefinition = redefined_catch_def(def);
|
||
|
|
const name = def.name = redefinition ? redefinition.name : next_name();
|
||
|
|
def.orig.forEach(function(sym) {
|
||
|
|
sym.name = name;
|
||
|
|
});
|
||
|
|
def.references.forEach(function(sym) {
|
||
|
|
sym.name = name;
|
||
|
|
});
|
||
|
|
}
|
||
|
|
});
|
||
|
|
|
||
|
|
AST_Node.DEFMETHOD("tail_node", return_this);
|
||
|
|
AST_Sequence.DEFMETHOD("tail_node", function() {
|
||
|
|
return this.expressions[this.expressions.length - 1];
|
||
|
|
});
|
||
|
|
|
||
|
|
AST_Toplevel.DEFMETHOD("compute_char_frequency", function(options) {
|
||
|
|
options = format_mangler_options(options);
|
||
|
|
var nth_identifier = options.nth_identifier;
|
||
|
|
if (!nth_identifier.reset || !nth_identifier.consider || !nth_identifier.sort) {
|
||
|
|
// If the identifier mangler is invariant, skip computing character frequency.
|
||
|
|
return;
|
||
|
|
}
|
||
|
|
nth_identifier.reset();
|
||
|
|
|
||
|
|
try {
|
||
|
|
AST_Node.prototype.print = function(stream, force_parens) {
|
||
|
|
this._print(stream, force_parens);
|
||
|
|
if (this instanceof AST_Symbol && !this.unmangleable(options)) {
|
||
|
|
nth_identifier.consider(this.name, -1);
|
||
|
|
} else if (options.properties) {
|
||
|
|
if (this instanceof AST_DotHash) {
|
||
|
|
nth_identifier.consider("#" + this.property, -1);
|
||
|
|
} else if (this instanceof AST_Dot) {
|
||
|
|
nth_identifier.consider(this.property, -1);
|
||
|
|
} else if (this instanceof AST_Sub) {
|
||
|
|
skip_string(this.property);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
};
|
||
|
|
nth_identifier.consider(this.print_to_string(), 1);
|
||
|
|
} finally {
|
||
|
|
AST_Node.prototype.print = AST_Node.prototype._print;
|
||
|
|
}
|
||
|
|
nth_identifier.sort();
|
||
|
|
|
||
|
|
function skip_string(node) {
|
||
|
|
if (node instanceof AST_String) {
|
||
|
|
nth_identifier.consider(node.value, -1);
|
||
|
|
} else if (node instanceof AST_Conditional) {
|
||
|
|
skip_string(node.consequent);
|
||
|
|
skip_string(node.alternative);
|
||
|
|
} else if (node instanceof AST_Sequence) {
|
||
|
|
skip_string(node.tail_node());
|
||
|
|
}
|
||
|
|
}
|
||
|
|
});
|
||
|
|
|
||
|
|
const base54 = (() => {
|
||
|
|
const leading = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ$_".split("");
|
||
|
|
const digits = "0123456789".split("");
|
||
|
|
let chars;
|
||
|
|
let frequency;
|
||
|
|
function reset() {
|
||
|
|
frequency = new Map();
|
||
|
|
leading.forEach(function(ch) {
|
||
|
|
frequency.set(ch, 0);
|
||
|
|
});
|
||
|
|
digits.forEach(function(ch) {
|
||
|
|
frequency.set(ch, 0);
|
||
|
|
});
|
||
|
|
}
|
||
|
|
function consider(str, delta) {
|
||
|
|
for (var i = str.length; --i >= 0;) {
|
||
|
|
frequency.set(str[i], frequency.get(str[i]) + delta);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
function compare(a, b) {
|
||
|
|
return frequency.get(b) - frequency.get(a);
|
||
|
|
}
|
||
|
|
function sort() {
|
||
|
|
chars = mergeSort(leading, compare).concat(mergeSort(digits, compare));
|
||
|
|
}
|
||
|
|
// Ensure this is in a usable initial state.
|
||
|
|
reset();
|
||
|
|
sort();
|
||
|
|
function base54(num) {
|
||
|
|
var ret = "", base = 54;
|
||
|
|
num++;
|
||
|
|
do {
|
||
|
|
num--;
|
||
|
|
ret += chars[num % base];
|
||
|
|
num = Math.floor(num / base);
|
||
|
|
base = 64;
|
||
|
|
} while (num > 0);
|
||
|
|
return ret;
|
||
|
|
}
|
||
|
|
|
||
|
|
return {
|
||
|
|
get: base54,
|
||
|
|
consider,
|
||
|
|
reset,
|
||
|
|
sort
|
||
|
|
};
|
||
|
|
})();
|
||
|
|
|
||
|
|
export {
|
||
|
|
base54,
|
||
|
|
SymbolDef,
|
||
|
|
};
|