| /*********************************************************************** |
| |
| A JavaScript tokenizer / parser / beautifier / compressor. |
| |
| This version is suitable for Node.js. With minimal changes (the |
| exports stuff) it should work on any JS platform. |
| |
| This file implements some AST processors. They work on data built |
| by parse-js. |
| |
| Exported functions: |
| |
| - ast_mangle(ast, options) -- mangles the variable/function names |
| in the AST. Returns an AST. |
| |
| - ast_squeeze(ast) -- employs various optimizations to make the |
| final generated code even smaller. Returns an AST. |
| |
| - gen_code(ast, options) -- generates JS code from the AST. Pass |
| true (or an object, see the code for some options) as second |
| argument to get "pretty" (indented) code. |
| |
| -------------------------------- (C) --------------------------------- |
| |
| Author: Mihai Bazon |
| <mihai.bazon@gmail.com> |
| http://mihai.bazon.net/blog |
| |
| Distributed under the BSD license: |
| |
| Copyright 2010 (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. |
| |
| ***********************************************************************/ |
| |
| var jsp = require("./parse-js"), |
| slice = jsp.slice, |
| member = jsp.member, |
| PRECEDENCE = jsp.PRECEDENCE, |
| OPERATORS = jsp.OPERATORS; |
| |
| /* -----[ helper for AST traversal ]----- */ |
| |
| function ast_walker(ast) { |
| function _vardefs(defs) { |
| return [ this[0], MAP(defs, function(def){ |
| var a = [ def[0] ]; |
| if (def.length > 1) |
| a[1] = walk(def[1]); |
| return a; |
| }) ]; |
| }; |
| var walkers = { |
| "string": function(str) { |
| return [ this[0], str ]; |
| }, |
| "num": function(num) { |
| return [ this[0], num ]; |
| }, |
| "name": function(name) { |
| return [ this[0], name ]; |
| }, |
| "toplevel": function(statements) { |
| return [ this[0], MAP(statements, walk) ]; |
| }, |
| "block": function(statements) { |
| var out = [ this[0] ]; |
| if (statements != null) |
| out.push(MAP(statements, walk)); |
| return out; |
| }, |
| "var": _vardefs, |
| "const": _vardefs, |
| "try": function(t, c, f) { |
| return [ |
| this[0], |
| MAP(t, walk), |
| c != null ? [ c[0], MAP(c[1], walk) ] : null, |
| f != null ? MAP(f, walk) : null |
| ]; |
| }, |
| "throw": function(expr) { |
| return [ this[0], walk(expr) ]; |
| }, |
| "new": function(ctor, args) { |
| return [ this[0], walk(ctor), MAP(args, walk) ]; |
| }, |
| "switch": function(expr, body) { |
| return [ this[0], walk(expr), MAP(body, function(branch){ |
| return [ branch[0] ? walk(branch[0]) : null, |
| MAP(branch[1], walk) ]; |
| }) ]; |
| }, |
| "break": function(label) { |
| return [ this[0], label ]; |
| }, |
| "continue": function(label) { |
| return [ this[0], label ]; |
| }, |
| "conditional": function(cond, t, e) { |
| return [ this[0], walk(cond), walk(t), walk(e) ]; |
| }, |
| "assign": function(op, lvalue, rvalue) { |
| return [ this[0], op, walk(lvalue), walk(rvalue) ]; |
| }, |
| "dot": function(expr) { |
| return [ this[0], walk(expr) ].concat(slice(arguments, 1)); |
| }, |
| "call": function(expr, args) { |
| return [ this[0], walk(expr), MAP(args, walk) ]; |
| }, |
| "function": function(name, args, body) { |
| return [ this[0], name, args.slice(), MAP(body, walk) ]; |
| }, |
| "defun": function(name, args, body) { |
| return [ this[0], name, args.slice(), MAP(body, walk) ]; |
| }, |
| "if": function(conditional, t, e) { |
| return [ this[0], walk(conditional), walk(t), walk(e) ]; |
| }, |
| "for": function(init, cond, step, block) { |
| return [ this[0], walk(init), walk(cond), walk(step), walk(block) ]; |
| }, |
| "for-in": function(vvar, key, hash, block) { |
| return [ this[0], walk(vvar), walk(key), walk(hash), walk(block) ]; |
| }, |
| "while": function(cond, block) { |
| return [ this[0], walk(cond), walk(block) ]; |
| }, |
| "do": function(cond, block) { |
| return [ this[0], walk(cond), walk(block) ]; |
| }, |
| "return": function(expr) { |
| return [ this[0], walk(expr) ]; |
| }, |
| "binary": function(op, left, right) { |
| return [ this[0], op, walk(left), walk(right) ]; |
| }, |
| "unary-prefix": function(op, expr) { |
| return [ this[0], op, walk(expr) ]; |
| }, |
| "unary-postfix": function(op, expr) { |
| return [ this[0], op, walk(expr) ]; |
| }, |
| "sub": function(expr, subscript) { |
| return [ this[0], walk(expr), walk(subscript) ]; |
| }, |
| "object": function(props) { |
| return [ this[0], MAP(props, function(p){ |
| return p.length == 2 |
| ? [ p[0], walk(p[1]) ] |
| : [ p[0], walk(p[1]), p[2] ]; // get/set-ter |
| }) ]; |
| }, |
| "regexp": function(rx, mods) { |
| return [ this[0], rx, mods ]; |
| }, |
| "array": function(elements) { |
| return [ this[0], MAP(elements, walk) ]; |
| }, |
| "stat": function(stat) { |
| return [ this[0], walk(stat) ]; |
| }, |
| "seq": function() { |
| return [ this[0] ].concat(MAP(slice(arguments), walk)); |
| }, |
| "label": function(name, block) { |
| return [ this[0], name, walk(block) ]; |
| }, |
| "with": function(expr, block) { |
| return [ this[0], walk(expr), walk(block) ]; |
| }, |
| "atom": function(name) { |
| return [ this[0], name ]; |
| } |
| }; |
| |
| var user = {}; |
| var stack = []; |
| function walk(ast) { |
| if (ast == null) |
| return null; |
| try { |
| stack.push(ast); |
| var type = ast[0]; |
| var gen = user[type]; |
| if (gen) { |
| var ret = gen.apply(ast, ast.slice(1)); |
| if (ret != null) |
| return ret; |
| } |
| gen = walkers[type]; |
| return gen.apply(ast, ast.slice(1)); |
| } finally { |
| stack.pop(); |
| } |
| }; |
| |
| function with_walkers(walkers, cont){ |
| var save = {}, i; |
| for (i in walkers) if (HOP(walkers, i)) { |
| save[i] = user[i]; |
| user[i] = walkers[i]; |
| } |
| var ret = cont(); |
| for (i in save) if (HOP(save, i)) { |
| if (!save[i]) delete user[i]; |
| else user[i] = save[i]; |
| } |
| return ret; |
| }; |
| |
| return { |
| walk: walk, |
| with_walkers: with_walkers, |
| parent: function() { |
| return stack[stack.length - 2]; // last one is current node |
| }, |
| stack: function() { |
| return stack; |
| } |
| }; |
| }; |
| |
| /* -----[ Scope and mangling ]----- */ |
| |
| function Scope(parent) { |
| this.names = {}; // names defined in this scope |
| this.mangled = {}; // mangled names (orig.name => mangled) |
| this.rev_mangled = {}; // reverse lookup (mangled => orig.name) |
| this.cname = -1; // current mangled name |
| this.refs = {}; // names referenced from this scope |
| this.uses_with = false; // will become TRUE if with() is detected in this or any subscopes |
| this.uses_eval = false; // will become TRUE if eval() is detected in this or any subscopes |
| this.parent = parent; // parent scope |
| this.children = []; // sub-scopes |
| if (parent) { |
| this.level = parent.level + 1; |
| parent.children.push(this); |
| } else { |
| this.level = 0; |
| } |
| }; |
| |
| var base54 = (function(){ |
| var DIGITS = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ$_"; |
| return function(num) { |
| var ret = ""; |
| do { |
| ret = DIGITS.charAt(num % 54) + ret; |
| num = Math.floor(num / 54); |
| } while (num > 0); |
| return ret; |
| }; |
| })(); |
| |
| Scope.prototype = { |
| has: function(name) { |
| for (var s = this; s; s = s.parent) |
| if (HOP(s.names, name)) |
| return s; |
| }, |
| has_mangled: function(mname) { |
| for (var s = this; s; s = s.parent) |
| if (HOP(s.rev_mangled, mname)) |
| return s; |
| }, |
| toJSON: function() { |
| return { |
| names: this.names, |
| uses_eval: this.uses_eval, |
| uses_with: this.uses_with |
| }; |
| }, |
| |
| next_mangled: function() { |
| // we must be careful that the new mangled name: |
| // |
| // 1. doesn't shadow a mangled name from a parent |
| // scope, unless we don't reference the original |
| // name from this scope OR from any sub-scopes! |
| // This will get slow. |
| // |
| // 2. doesn't shadow an original name from a parent |
| // scope, in the event that the name is not mangled |
| // in the parent scope and we reference that name |
| // here OR IN ANY SUBSCOPES! |
| // |
| // 3. doesn't shadow a name that is referenced but not |
| // defined (possibly global defined elsewhere). |
| for (;;) { |
| var m = base54(++this.cname), prior; |
| |
| // case 1. |
| prior = this.has_mangled(m); |
| if (prior && this.refs[prior.rev_mangled[m]] === prior) |
| continue; |
| |
| // case 2. |
| prior = this.has(m); |
| if (prior && prior !== this && this.refs[m] === prior && !prior.has_mangled(m)) |
| continue; |
| |
| // case 3. |
| if (HOP(this.refs, m) && this.refs[m] == null) |
| continue; |
| |
| // I got "do" once. :-/ |
| if (!is_identifier(m)) |
| continue; |
| |
| return m; |
| } |
| }, |
| get_mangled: function(name, newMangle) { |
| if (this.uses_eval || this.uses_with) return name; // no mangle if eval or with is in use |
| var s = this.has(name); |
| if (!s) return name; // not in visible scope, no mangle |
| if (HOP(s.mangled, name)) return s.mangled[name]; // already mangled in this scope |
| if (!newMangle) return name; // not found and no mangling requested |
| |
| var m = s.next_mangled(); |
| s.rev_mangled[m] = name; |
| return s.mangled[name] = m; |
| }, |
| define: function(name) { |
| if (name != null) |
| return this.names[name] = name; |
| } |
| }; |
| |
| function ast_add_scope(ast) { |
| |
| var current_scope = null; |
| var w = ast_walker(), walk = w.walk; |
| var having_eval = []; |
| |
| function with_new_scope(cont) { |
| current_scope = new Scope(current_scope); |
| var ret = current_scope.body = cont(); |
| ret.scope = current_scope; |
| current_scope = current_scope.parent; |
| return ret; |
| }; |
| |
| function define(name) { |
| return current_scope.define(name); |
| }; |
| |
| function reference(name) { |
| current_scope.refs[name] = true; |
| }; |
| |
| function _lambda(name, args, body) { |
| return [ this[0], this[0] == "defun" ? define(name) : name, args, with_new_scope(function(){ |
| MAP(args, define); |
| return MAP(body, walk); |
| })]; |
| }; |
| |
| return with_new_scope(function(){ |
| // process AST |
| var ret = w.with_walkers({ |
| "function": _lambda, |
| "defun": _lambda, |
| "with": function(expr, block) { |
| for (var s = current_scope; s; s = s.parent) |
| s.uses_with = true; |
| }, |
| "var": function(defs) { |
| MAP(defs, function(d){ define(d[0]) }); |
| }, |
| "const": function(defs) { |
| MAP(defs, function(d){ define(d[0]) }); |
| }, |
| "try": function(t, c, f) { |
| if (c != null) return [ |
| this[0], |
| MAP(t, walk), |
| [ define(c[0]), MAP(c[1], walk) ], |
| f != null ? MAP(f, walk) : null |
| ]; |
| }, |
| "name": function(name) { |
| if (name == "eval") |
| having_eval.push(current_scope); |
| reference(name); |
| } |
| }, function(){ |
| return walk(ast); |
| }); |
| |
| // the reason why we need an additional pass here is |
| // that names can be used prior to their definition. |
| |
| // scopes where eval was detected and their parents |
| // are marked with uses_eval, unless they define the |
| // "eval" name. |
| MAP(having_eval, function(scope){ |
| if (!scope.has("eval")) while (scope) { |
| scope.uses_eval = true; |
| scope = scope.parent; |
| } |
| }); |
| |
| // for referenced names it might be useful to know |
| // their origin scope. current_scope here is the |
| // toplevel one. |
| function fixrefs(scope, i) { |
| // do children first; order shouldn't matter |
| for (i = scope.children.length; --i >= 0;) |
| fixrefs(scope.children[i]); |
| for (i in scope.refs) if (HOP(scope.refs, i)) { |
| // find origin scope and propagate the reference to origin |
| for (var origin = scope.has(i), s = scope; s; s = s.parent) { |
| s.refs[i] = origin; |
| if (s === origin) break; |
| } |
| } |
| }; |
| fixrefs(current_scope); |
| |
| return ret; |
| }); |
| |
| }; |
| |
| /* -----[ mangle names ]----- */ |
| |
| function ast_mangle(ast, options) { |
| var w = ast_walker(), walk = w.walk, scope; |
| options = options || {}; |
| |
| function get_mangled(name, newMangle) { |
| if (!options.toplevel && !scope.parent) return name; // don't mangle toplevel |
| if (options.except && member(name, options.except)) |
| return name; |
| return scope.get_mangled(name, newMangle); |
| }; |
| |
| function _lambda(name, args, body) { |
| if (name) name = get_mangled(name); |
| body = with_scope(body.scope, function(){ |
| args = MAP(args, function(name){ return get_mangled(name) }); |
| return MAP(body, walk); |
| }); |
| return [ this[0], name, args, body ]; |
| }; |
| |
| function with_scope(s, cont) { |
| var _scope = scope; |
| scope = s; |
| for (var i in s.names) if (HOP(s.names, i)) { |
| get_mangled(i, true); |
| } |
| var ret = cont(); |
| ret.scope = s; |
| scope = _scope; |
| return ret; |
| }; |
| |
| function _vardefs(defs) { |
| return [ this[0], MAP(defs, function(d){ |
| return [ get_mangled(d[0]), walk(d[1]) ]; |
| }) ]; |
| }; |
| |
| return w.with_walkers({ |
| "function": _lambda, |
| "defun": function() { |
| // move function declarations to the top when |
| // they are not in some block. |
| var ast = _lambda.apply(this, arguments); |
| switch (w.parent()[0]) { |
| case "toplevel": |
| case "function": |
| case "defun": |
| return MAP.at_top(ast); |
| } |
| return ast; |
| }, |
| "var": _vardefs, |
| "const": _vardefs, |
| "name": function(name) { |
| return [ this[0], get_mangled(name) ]; |
| }, |
| "try": function(t, c, f) { |
| return [ this[0], |
| MAP(t, walk), |
| c != null ? [ get_mangled(c[0]), MAP(c[1], walk) ] : null, |
| f != null ? MAP(f, walk) : null ]; |
| }, |
| "toplevel": function(body) { |
| var self = this; |
| return with_scope(self.scope, function(){ |
| return [ self[0], MAP(body, walk) ]; |
| }); |
| } |
| }, function() { |
| return walk(ast_add_scope(ast)); |
| }); |
| }; |
| |
| /* -----[ |
| - compress foo["bar"] into foo.bar, |
| - remove block brackets {} where possible |
| - join consecutive var declarations |
| - various optimizations for IFs: |
| - if (cond) foo(); else bar(); ==> cond?foo():bar(); |
| - if (cond) foo(); ==> cond&&foo(); |
| - if (foo) return bar(); else return baz(); ==> return foo?bar():baz(); // also for throw |
| - if (foo) return bar(); else something(); ==> {if(foo)return bar();something()} |
| ]----- */ |
| |
| var warn = function(){}; |
| |
| function best_of(ast1, ast2) { |
| return gen_code(ast1).length > gen_code(ast2[0] == "stat" ? ast2[1] : ast2).length ? ast2 : ast1; |
| }; |
| |
| function last_stat(b) { |
| if (b[0] == "block" && b[1] && b[1].length > 0) |
| return b[1][b[1].length - 1]; |
| return b; |
| } |
| |
| function aborts(t) { |
| if (t) { |
| t = last_stat(t); |
| if (t[0] == "return" || t[0] == "break" || t[0] == "continue" || t[0] == "throw") |
| return true; |
| } |
| }; |
| |
| function boolean_expr(expr) { |
| return ( (expr[0] == "unary-prefix" |
| && member(expr[1], [ "!", "delete" ])) || |
| |
| (expr[0] == "binary" |
| && member(expr[1], [ "in", "instanceof", "==", "!=", "===", "!==", "<", "<=", ">=", ">" ])) || |
| |
| (expr[0] == "binary" |
| && member(expr[1], [ "&&", "||" ]) |
| && boolean_expr(expr[2]) |
| && boolean_expr(expr[3])) || |
| |
| (expr[0] == "conditional" |
| && boolean_expr(expr[2]) |
| && boolean_expr(expr[3])) || |
| |
| (expr[0] == "assign" |
| && expr[1] === true |
| && boolean_expr(expr[3])) || |
| |
| (expr[0] == "seq" |
| && boolean_expr(expr[expr.length - 1])) |
| ); |
| }; |
| |
| function make_conditional(c, t, e) { |
| if (c[0] == "unary-prefix" && c[1] == "!") { |
| return e ? [ "conditional", c[2], e, t ] : [ "binary", "||", c[2], t ]; |
| } else { |
| return e ? [ "conditional", c, t, e ] : [ "binary", "&&", c, t ]; |
| } |
| }; |
| |
| function empty(b) { |
| return !b || (b[0] == "block" && (!b[1] || b[1].length == 0)); |
| }; |
| |
| function is_string(node) { |
| return (node[0] == "string" || |
| node[0] == "unary-prefix" && node[1] == "typeof" || |
| node[0] == "binary" && node[1] == "+" && |
| (is_string(node[2]) || is_string(node[3]))); |
| }; |
| |
| var when_constant = (function(){ |
| |
| var $NOT_CONSTANT = {}; |
| |
| // this can only evaluate constant expressions. If it finds anything |
| // not constant, it throws $NOT_CONSTANT. |
| function evaluate(expr) { |
| switch (expr[0]) { |
| case "string": |
| case "num": |
| return expr[1]; |
| case "name": |
| case "atom": |
| switch (expr[1]) { |
| case "true": return true; |
| case "false": return false; |
| } |
| break; |
| case "unary-prefix": |
| switch (expr[1]) { |
| case "!": return !evaluate(expr[2]); |
| case "typeof": return typeof evaluate(expr[2]); |
| case "~": return ~evaluate(expr[2]); |
| case "-": return -evaluate(expr[2]); |
| case "+": return +evaluate(expr[2]); |
| } |
| break; |
| case "binary": |
| var left = expr[2], right = expr[3]; |
| switch (expr[1]) { |
| case "&&" : return evaluate(left) && evaluate(right); |
| case "||" : return evaluate(left) || evaluate(right); |
| case "|" : return evaluate(left) | evaluate(right); |
| case "&" : return evaluate(left) & evaluate(right); |
| case "^" : return evaluate(left) ^ evaluate(right); |
| case "+" : return evaluate(left) + evaluate(right); |
| case "*" : return evaluate(left) * evaluate(right); |
| case "/" : return evaluate(left) / evaluate(right); |
| case "-" : return evaluate(left) - evaluate(right); |
| case "<<" : return evaluate(left) << evaluate(right); |
| case ">>" : return evaluate(left) >> evaluate(right); |
| case ">>>" : return evaluate(left) >>> evaluate(right); |
| case "==" : return evaluate(left) == evaluate(right); |
| case "===" : return evaluate(left) === evaluate(right); |
| case "!=" : return evaluate(left) != evaluate(right); |
| case "!==" : return evaluate(left) !== evaluate(right); |
| case "<" : return evaluate(left) < evaluate(right); |
| case "<=" : return evaluate(left) <= evaluate(right); |
| case ">" : return evaluate(left) > evaluate(right); |
| case ">=" : return evaluate(left) >= evaluate(right); |
| case "in" : return evaluate(left) in evaluate(right); |
| case "instanceof" : return evaluate(left) instanceof evaluate(right); |
| } |
| } |
| throw $NOT_CONSTANT; |
| }; |
| |
| return function(expr, yes, no) { |
| try { |
| var val = evaluate(expr), ast; |
| switch (typeof val) { |
| case "string": ast = [ "string", val ]; break; |
| case "number": ast = [ "num", val ]; break; |
| case "boolean": ast = [ "name", String(val) ]; break; |
| default: throw new Error("Can't handle constant of type: " + (typeof val)); |
| } |
| return yes.call(expr, ast, val); |
| } catch(ex) { |
| if (ex === $NOT_CONSTANT) { |
| if (expr[0] == "binary" |
| && (expr[1] == "===" || expr[1] == "!==") |
| && ((is_string(expr[2]) && is_string(expr[3])) |
| || (boolean_expr(expr[2]) && boolean_expr(expr[3])))) { |
| expr[1] = expr[1].substr(0, 2); |
| } |
| return no ? no.call(expr, expr) : null; |
| } |
| else throw ex; |
| } |
| }; |
| |
| })(); |
| |
| function warn_unreachable(ast) { |
| if (!empty(ast)) |
| warn("Dropping unreachable code: " + gen_code(ast, true)); |
| }; |
| |
| function ast_squeeze(ast, options) { |
| options = defaults(options, { |
| make_seqs : true, |
| dead_code : true, |
| keep_comps : true, |
| no_warnings : false |
| }); |
| |
| var w = ast_walker(), walk = w.walk, scope; |
| |
| function negate(c) { |
| var not_c = [ "unary-prefix", "!", c ]; |
| switch (c[0]) { |
| case "unary-prefix": |
| return c[1] == "!" && boolean_expr(c[2]) ? c[2] : not_c; |
| case "seq": |
| c = slice(c); |
| c[c.length - 1] = negate(c[c.length - 1]); |
| return c; |
| case "conditional": |
| return best_of(not_c, [ "conditional", c[1], negate(c[2]), negate(c[3]) ]); |
| case "binary": |
| var op = c[1], left = c[2], right = c[3]; |
| if (!options.keep_comps) switch (op) { |
| case "<=" : return [ "binary", ">", left, right ]; |
| case "<" : return [ "binary", ">=", left, right ]; |
| case ">=" : return [ "binary", "<", left, right ]; |
| case ">" : return [ "binary", "<=", left, right ]; |
| } |
| switch (op) { |
| case "==" : return [ "binary", "!=", left, right ]; |
| case "!=" : return [ "binary", "==", left, right ]; |
| case "===" : return [ "binary", "!==", left, right ]; |
| case "!==" : return [ "binary", "===", left, right ]; |
| case "&&" : return best_of(not_c, [ "binary", "||", negate(left), negate(right) ]); |
| case "||" : return best_of(not_c, [ "binary", "&&", negate(left), negate(right) ]); |
| } |
| break; |
| } |
| return not_c; |
| }; |
| |
| function with_scope(s, cont) { |
| var _scope = scope; |
| scope = s; |
| var ret = cont(); |
| ret.scope = s; |
| scope = _scope; |
| return ret; |
| }; |
| |
| function rmblock(block) { |
| if (block != null && block[0] == "block" && block[1]) { |
| if (block[1].length == 1) |
| block = block[1][0]; |
| else if (block[1].length == 0) |
| block = [ "block" ]; |
| } |
| return block; |
| }; |
| |
| function _lambda(name, args, body) { |
| return [ this[0], name, args, with_scope(body.scope, function(){ |
| return tighten(MAP(body, walk), "lambda"); |
| }) ]; |
| }; |
| |
| // we get here for blocks that have been already transformed. |
| // this function does a few things: |
| // 1. discard useless blocks |
| // 2. join consecutive var declarations |
| // 3. remove obviously dead code |
| // 4. transform consecutive statements using the comma operator |
| // 5. if block_type == "lambda" and it detects constructs like if(foo) return ... - rewrite like if (!foo) { ... } |
| function tighten(statements, block_type) { |
| statements = statements.reduce(function(a, stat){ |
| if (stat[0] == "block") { |
| if (stat[1]) { |
| a.push.apply(a, stat[1]); |
| } |
| } else { |
| a.push(stat); |
| } |
| return a; |
| }, []); |
| |
| statements = (function(a, prev){ |
| statements.forEach(function(cur){ |
| if (prev && ((cur[0] == "var" && prev[0] == "var") || |
| (cur[0] == "const" && prev[0] == "const"))) { |
| prev[1] = prev[1].concat(cur[1]); |
| } else { |
| a.push(cur); |
| prev = cur; |
| } |
| }); |
| return a; |
| })([]); |
| |
| if (options.dead_code) statements = (function(a, has_quit){ |
| statements.forEach(function(st){ |
| if (has_quit) { |
| if (member(st[0], [ "function", "defun" , "var", "const" ])) { |
| a.push(st); |
| } |
| else if (!options.no_warnings) |
| warn_unreachable(st); |
| } |
| else { |
| a.push(st); |
| if (member(st[0], [ "return", "throw", "break", "continue" ])) |
| has_quit = true; |
| } |
| }); |
| return a; |
| })([]); |
| |
| if (options.make_seqs) statements = (function(a, prev) { |
| statements.forEach(function(cur){ |
| if (prev && prev[0] == "stat" && cur[0] == "stat") { |
| prev[1] = [ "seq", prev[1], cur[1] ]; |
| } else { |
| a.push(cur); |
| prev = cur; |
| } |
| }); |
| return a; |
| })([]); |
| |
| if (block_type == "lambda") statements = (function(i, a, stat){ |
| while (i < statements.length) { |
| stat = statements[i++]; |
| if (stat[0] == "if" && !stat[3]) { |
| if (stat[2][0] == "return" && stat[2][1] == null) { |
| a.push(make_if(negate(stat[1]), [ "block", statements.slice(i) ])); |
| break; |
| } |
| var last = last_stat(stat[2]); |
| if (last[0] == "return" && last[1] == null) { |
| a.push(make_if(stat[1], [ "block", stat[2][1].slice(0, -1) ], [ "block", statements.slice(i) ])); |
| break; |
| } |
| } |
| a.push(stat); |
| } |
| return a; |
| })(0, []); |
| |
| return statements; |
| }; |
| |
| function make_if(c, t, e) { |
| return when_constant(c, function(ast, val){ |
| if (val) { |
| warn_unreachable(e); |
| return t; |
| } else { |
| warn_unreachable(t); |
| return e; |
| } |
| }, function() { |
| return make_real_if(c, t, e); |
| }); |
| }; |
| |
| function make_real_if(c, t, e) { |
| c = walk(c); |
| t = walk(t); |
| e = walk(e); |
| |
| if (empty(t)) { |
| c = negate(c); |
| t = e; |
| e = null; |
| } else if (empty(e)) { |
| e = null; |
| } else { |
| // if we have both else and then, maybe it makes sense to switch them? |
| (function(){ |
| var a = gen_code(c); |
| var n = negate(c); |
| var b = gen_code(n); |
| if (b.length < a.length) { |
| var tmp = t; |
| t = e; |
| e = tmp; |
| c = n; |
| } |
| })(); |
| } |
| if (empty(e) && empty(t)) |
| return [ "stat", c ]; |
| var ret = [ "if", c, t, e ]; |
| if (t[0] == "if" && empty(t[3]) && empty(e)) { |
| ret = best_of(ret, walk([ "if", [ "binary", "&&", c, t[1] ], t[2] ])); |
| } |
| else if (t[0] == "stat") { |
| if (e) { |
| if (e[0] == "stat") { |
| ret = best_of(ret, [ "stat", make_conditional(c, t[1], e[1]) ]); |
| } |
| } |
| else { |
| ret = best_of(ret, [ "stat", make_conditional(c, t[1]) ]); |
| } |
| } |
| else if (e && t[0] == e[0] && (t[0] == "return" || t[0] == "throw") && t[1] && e[1]) { |
| ret = best_of(ret, [ t[0], make_conditional(c, t[1], e[1] ) ]); |
| } |
| else if (e && aborts(t)) { |
| ret = [ [ "if", c, t ] ]; |
| if (e[0] == "block") { |
| if (e[1]) ret = ret.concat(e[1]); |
| } |
| else { |
| ret.push(e); |
| } |
| ret = walk([ "block", ret ]); |
| } |
| else if (t && aborts(e)) { |
| ret = [ [ "if", negate(c), e ] ]; |
| if (t[0] == "block") { |
| if (t[1]) ret = ret.concat(t[1]); |
| } else { |
| ret.push(t); |
| } |
| ret = walk([ "block", ret ]); |
| } |
| return ret; |
| }; |
| |
| function _do_while(cond, body) { |
| return when_constant(cond, function(cond, val){ |
| if (!val) { |
| warn_unreachable(body); |
| return [ "block" ]; |
| } else { |
| return [ "for", null, null, null, walk(body) ]; |
| } |
| }); |
| }; |
| |
| return w.with_walkers({ |
| "sub": function(expr, subscript) { |
| if (subscript[0] == "string") { |
| var name = subscript[1]; |
| if (is_identifier(name)) |
| return [ "dot", walk(expr), name ]; |
| else if (/^[1-9][0-9]*$/.test(name) || name === "0") |
| return [ "sub", walk(expr), [ "num", parseInt(name, 10) ] ]; |
| } |
| }, |
| "if": make_if, |
| "toplevel": function(body) { |
| return [ "toplevel", with_scope(this.scope, function(){ |
| return tighten(MAP(body, walk)); |
| }) ]; |
| }, |
| "switch": function(expr, body) { |
| var last = body.length - 1; |
| return [ "switch", walk(expr), MAP(body, function(branch, i){ |
| var block = tighten(MAP(branch[1], walk)); |
| if (i == last && block.length > 0) { |
| var node = block[block.length - 1]; |
| if (node[0] == "break" && !node[1]) |
| block.pop(); |
| } |
| return [ branch[0] ? walk(branch[0]) : null, block ]; |
| }) ]; |
| }, |
| "function": function() { |
| var ret = _lambda.apply(this, arguments); |
| if (ret[1] && !HOP(scope.refs, ret[1])) { |
| ret[1] = null; |
| } |
| return ret; |
| }, |
| "defun": _lambda, |
| "block": function(body) { |
| if (body) return rmblock([ "block", tighten(MAP(body, walk)) ]); |
| }, |
| "binary": function(op, left, right) { |
| return when_constant([ "binary", op, walk(left), walk(right) ], function yes(c){ |
| return best_of(walk(c), this); |
| }, function no() { |
| return this; |
| }); |
| }, |
| "conditional": function(c, t, e) { |
| return make_conditional(walk(c), walk(t), walk(e)); |
| }, |
| "try": function(t, c, f) { |
| return [ |
| "try", |
| tighten(MAP(t, walk)), |
| c != null ? [ c[0], tighten(MAP(c[1], walk)) ] : null, |
| f != null ? tighten(MAP(f, walk)) : null |
| ]; |
| }, |
| "unary-prefix": function(op, expr) { |
| expr = walk(expr); |
| var ret = [ "unary-prefix", op, expr ]; |
| if (op == "!") |
| ret = best_of(ret, negate(expr)); |
| return when_constant(ret, function(ast, val){ |
| return walk(ast); // it's either true or false, so minifies to !0 or !1 |
| }, function() { return ret }); |
| }, |
| "name": function(name) { |
| switch (name) { |
| case "true": return [ "unary-prefix", "!", [ "num", 0 ]]; |
| case "false": return [ "unary-prefix", "!", [ "num", 1 ]]; |
| } |
| }, |
| "new": function(ctor, args) { |
| if (ctor[0] == "name" && ctor[1] == "Array" && !scope.has("Array")) { |
| if (args.length != 1) { |
| return [ "array", args ]; |
| } else { |
| return [ "call", [ "name", "Array" ], args ]; |
| } |
| } |
| }, |
| "call": function(expr, args) { |
| if (expr[0] == "name" && expr[1] == "Array" && args.length != 1 && !scope.has("Array")) { |
| return [ "array", args ]; |
| } |
| }, |
| "while": _do_while, |
| "do": _do_while |
| }, function() { |
| return walk(ast_add_scope(ast)); |
| }); |
| }; |
| |
| /* -----[ re-generate code from the AST ]----- */ |
| |
| var DOT_CALL_NO_PARENS = jsp.array_to_hash([ |
| "name", |
| "array", |
| "object", |
| "string", |
| "dot", |
| "sub", |
| "call", |
| "regexp" |
| ]); |
| |
| function make_string(str, ascii_only) { |
| var dq = 0, sq = 0; |
| str = str.replace(/[\\\b\f\n\r\t\x22\x27\u2028\u2029]/g, function(s){ |
| switch (s) { |
| case "\\": return "\\\\"; |
| case "\b": return "\\b"; |
| case "\f": return "\\f"; |
| case "\n": return "\\n"; |
| case "\r": return "\\r"; |
| case "\t": return "\\t"; |
| case "\u2028": return "\\u2028"; |
| case "\u2029": return "\\u2029"; |
| case '"': ++dq; return '"'; |
| case "'": ++sq; return "'"; |
| } |
| return s; |
| }); |
| if (ascii_only) str = to_ascii(str); |
| if (dq > sq) return "'" + str.replace(/\x27/g, "\\'") + "'"; |
| else return '"' + str.replace(/\x22/g, '\\"') + '"'; |
| }; |
| |
| function to_ascii(str) { |
| return str.replace(/[\u0080-\uffff]/g, function(ch) { |
| var code = ch.charCodeAt(0).toString(16); |
| while (code.length < 4) code = "0" + code; |
| return "\\u" + code; |
| }); |
| }; |
| |
| function gen_code(ast, options) { |
| options = defaults(options, { |
| indent_start : 0, |
| indent_level : 4, |
| quote_keys : false, |
| space_colon : false, |
| beautify : false, |
| ascii_only : false |
| }); |
| var beautify = !!options.beautify; |
| var indentation = 0, |
| newline = beautify ? "\n" : "", |
| space = beautify ? " " : ""; |
| |
| function encode_string(str) { |
| return make_string(str, options.ascii_only); |
| }; |
| |
| function make_name(name) { |
| name = name.toString(); |
| if (options.ascii_only) |
| name = to_ascii(name); |
| return name; |
| }; |
| |
| function indent(line) { |
| if (line == null) |
| line = ""; |
| if (beautify) |
| line = repeat_string(" ", options.indent_start + indentation * options.indent_level) + line; |
| return line; |
| }; |
| |
| function with_indent(cont, incr) { |
| if (incr == null) incr = 1; |
| indentation += incr; |
| try { return cont.apply(null, slice(arguments, 1)); } |
| finally { indentation -= incr; } |
| }; |
| |
| function add_spaces(a) { |
| if (beautify) |
| return a.join(" "); |
| var b = []; |
| for (var i = 0; i < a.length; ++i) { |
| var next = a[i + 1]; |
| b.push(a[i]); |
| if (next && |
| ((/[a-z0-9_\x24]$/i.test(a[i].toString()) && /^[a-z0-9_\x24]/i.test(next.toString())) || |
| (/[\+\-]$/.test(a[i].toString()) && /^[\+\-]/.test(next.toString())))) { |
| b.push(" "); |
| } |
| } |
| return b.join(""); |
| }; |
| |
| function add_commas(a) { |
| return a.join("," + space); |
| }; |
| |
| function parenthesize(expr) { |
| var gen = make(expr); |
| for (var i = 1; i < arguments.length; ++i) { |
| var el = arguments[i]; |
| if ((el instanceof Function && el(expr)) || expr[0] == el) |
| return "(" + gen + ")"; |
| } |
| return gen; |
| }; |
| |
| function best_of(a) { |
| if (a.length == 1) { |
| return a[0]; |
| } |
| if (a.length == 2) { |
| var b = a[1]; |
| a = a[0]; |
| return a.length <= b.length ? a : b; |
| } |
| return best_of([ a[0], best_of(a.slice(1)) ]); |
| }; |
| |
| function needs_parens(expr) { |
| if (expr[0] == "function" || expr[0] == "object") { |
| // dot/call on a literal function requires the |
| // function literal itself to be parenthesized |
| // only if it's the first "thing" in a |
| // statement. This means that the parent is |
| // "stat", but it could also be a "seq" and |
| // we're the first in this "seq" and the |
| // parent is "stat", and so on. Messy stuff, |
| // but it worths the trouble. |
| var a = slice($stack), self = a.pop(), p = a.pop(); |
| while (p) { |
| if (p[0] == "stat") return true; |
| if (((p[0] == "seq" || p[0] == "call" || p[0] == "dot" || p[0] == "sub" || p[0] == "conditional") && p[1] === self) || |
| ((p[0] == "binary" || p[0] == "assign" || p[0] == "unary-postfix") && p[2] === self)) { |
| self = p; |
| p = a.pop(); |
| } else { |
| return false; |
| } |
| } |
| } |
| return !HOP(DOT_CALL_NO_PARENS, expr[0]); |
| }; |
| |
| function make_num(num) { |
| var str = num.toString(10), a = [ str.replace(/^0\./, ".") ], m; |
| if (Math.floor(num) === num) { |
| a.push("0x" + num.toString(16).toLowerCase(), // probably pointless |
| "0" + num.toString(8)); // same. |
| if ((m = /^(.*?)(0+)$/.exec(num))) { |
| a.push(m[1] + "e" + m[2].length); |
| } |
| } else if ((m = /^0?\.(0+)(.*)$/.exec(num))) { |
| a.push(m[2] + "e-" + (m[1].length + m[2].length), |
| str.substr(str.indexOf("."))); |
| } |
| return best_of(a); |
| }; |
| |
| var generators = { |
| "string": encode_string, |
| "num": make_num, |
| "name": make_name, |
| "toplevel": function(statements) { |
| return make_block_statements(statements) |
| .join(newline + newline); |
| }, |
| "block": make_block, |
| "var": function(defs) { |
| return "var " + add_commas(MAP(defs, make_1vardef)) + ";"; |
| }, |
| "const": function(defs) { |
| return "const " + add_commas(MAP(defs, make_1vardef)) + ";"; |
| }, |
| "try": function(tr, ca, fi) { |
| var out = [ "try", make_block(tr) ]; |
| if (ca) out.push("catch", "(" + ca[0] + ")", make_block(ca[1])); |
| if (fi) out.push("finally", make_block(fi)); |
| return add_spaces(out); |
| }, |
| "throw": function(expr) { |
| return add_spaces([ "throw", make(expr) ]) + ";"; |
| }, |
| "new": function(ctor, args) { |
| args = args.length > 0 ? "(" + add_commas(MAP(args, make)) + ")" : ""; |
| return add_spaces([ "new", parenthesize(ctor, "seq", "binary", "conditional", "assign", function(expr){ |
| var w = ast_walker(), has_call = {}; |
| try { |
| w.with_walkers({ |
| "call": function() { throw has_call }, |
| "function": function() { return this } |
| }, function(){ |
| w.walk(expr); |
| }); |
| } catch(ex) { |
| if (ex === has_call) |
| return true; |
| throw ex; |
| } |
| }) + args ]); |
| }, |
| "switch": function(expr, body) { |
| return add_spaces([ "switch", "(" + make(expr) + ")", make_switch_block(body) ]); |
| }, |
| "break": function(label) { |
| var out = "break"; |
| if (label != null) |
| out += " " + make_name(label); |
| return out + ";"; |
| }, |
| "continue": function(label) { |
| var out = "continue"; |
| if (label != null) |
| out += " " + make_name(label); |
| return out + ";"; |
| }, |
| "conditional": function(co, th, el) { |
| return add_spaces([ parenthesize(co, "assign", "seq", "conditional"), "?", |
| parenthesize(th, "seq"), ":", |
| parenthesize(el, "seq") ]); |
| }, |
| "assign": function(op, lvalue, rvalue) { |
| if (op && op !== true) op += "="; |
| else op = "="; |
| return add_spaces([ make(lvalue), op, parenthesize(rvalue, "seq") ]); |
| }, |
| "dot": function(expr) { |
| var out = make(expr), i = 1; |
| if (expr[0] == "num") { |
| if (!/\./.test(expr[1])) |
| out += "."; |
| } else if (needs_parens(expr)) |
| out = "(" + out + ")"; |
| while (i < arguments.length) |
| out += "." + make_name(arguments[i++]); |
| return out; |
| }, |
| "call": function(func, args) { |
| var f = make(func); |
| if (needs_parens(func)) |
| f = "(" + f + ")"; |
| return f + "(" + add_commas(MAP(args, function(expr){ |
| return parenthesize(expr, "seq"); |
| })) + ")"; |
| }, |
| "function": make_function, |
| "defun": make_function, |
| "if": function(co, th, el) { |
| var out = [ "if", "(" + make(co) + ")", el ? make_then(th) : make(th) ]; |
| if (el) { |
| out.push("else", make(el)); |
| } |
| return add_spaces(out); |
| }, |
| "for": function(init, cond, step, block) { |
| var out = [ "for" ]; |
| init = (init != null ? make(init) : "").replace(/;*\s*$/, ";" + space); |
| cond = (cond != null ? make(cond) : "").replace(/;*\s*$/, ";" + space); |
| step = (step != null ? make(step) : "").replace(/;*\s*$/, ""); |
| var args = init + cond + step; |
| if (args == "; ; ") args = ";;"; |
| out.push("(" + args + ")", make(block)); |
| return add_spaces(out); |
| }, |
| "for-in": function(vvar, key, hash, block) { |
| return add_spaces([ "for", "(" + |
| (vvar ? make(vvar).replace(/;+$/, "") : make(key)), |
| "in", |
| make(hash) + ")", make(block) ]); |
| }, |
| "while": function(condition, block) { |
| return add_spaces([ "while", "(" + make(condition) + ")", make(block) ]); |
| }, |
| "do": function(condition, block) { |
| return add_spaces([ "do", make(block), "while", "(" + make(condition) + ")" ]) + ";"; |
| }, |
| "return": function(expr) { |
| var out = [ "return" ]; |
| if (expr != null) out.push(make(expr)); |
| return add_spaces(out) + ";"; |
| }, |
| "binary": function(operator, lvalue, rvalue) { |
| var left = make(lvalue), right = make(rvalue); |
| // XXX: I'm pretty sure other cases will bite here. |
| // we need to be smarter. |
| // adding parens all the time is the safest bet. |
| if (member(lvalue[0], [ "assign", "conditional", "seq" ]) || |
| lvalue[0] == "binary" && PRECEDENCE[operator] > PRECEDENCE[lvalue[1]]) { |
| left = "(" + left + ")"; |
| } |
| if (member(rvalue[0], [ "assign", "conditional", "seq" ]) || |
| rvalue[0] == "binary" && PRECEDENCE[operator] >= PRECEDENCE[rvalue[1]] && |
| !(rvalue[1] == operator && member(operator, [ "&&", "||", "*" ]))) { |
| right = "(" + right + ")"; |
| } |
| return add_spaces([ left, operator, right ]); |
| }, |
| "unary-prefix": function(operator, expr) { |
| var val = make(expr); |
| if (!(expr[0] == "num" || (expr[0] == "unary-prefix" && !HOP(OPERATORS, operator + expr[1])) || !needs_parens(expr))) |
| val = "(" + val + ")"; |
| return operator + (jsp.is_alphanumeric_char(operator.charAt(0)) ? " " : "") + val; |
| }, |
| "unary-postfix": function(operator, expr) { |
| var val = make(expr); |
| if (!(expr[0] == "num" || (expr[0] == "unary-postfix" && !HOP(OPERATORS, operator + expr[1])) || !needs_parens(expr))) |
| val = "(" + val + ")"; |
| return val + operator; |
| }, |
| "sub": function(expr, subscript) { |
| var hash = make(expr); |
| if (needs_parens(expr)) |
| hash = "(" + hash + ")"; |
| return hash + "[" + make(subscript) + "]"; |
| }, |
| "object": function(props) { |
| if (props.length == 0) |
| return "{}"; |
| return "{" + newline + with_indent(function(){ |
| return MAP(props, function(p){ |
| if (p.length == 3) { |
| // getter/setter. The name is in p[0], the arg.list in p[1][2], the |
| // body in p[1][3] and type ("get" / "set") in p[2]. |
| return indent(make_function(p[0], p[1][2], p[1][3], p[2])); |
| } |
| var key = p[0], val = make(p[1]); |
| if (options.quote_keys) { |
| key = encode_string(key); |
| } else if ((typeof key == "number" || !beautify && +key + "" == key) |
| && parseFloat(key) >= 0) { |
| key = make_num(+key); |
| } else if (!is_identifier(key)) { |
| key = encode_string(key); |
| } |
| return indent(add_spaces(beautify && options.space_colon |
| ? [ key, ":", val ] |
| : [ key + ":", val ])); |
| }).join("," + newline); |
| }) + newline + indent("}"); |
| }, |
| "regexp": function(rx, mods) { |
| return "/" + rx + "/" + mods; |
| }, |
| "array": function(elements) { |
| if (elements.length == 0) return "[]"; |
| return add_spaces([ "[", add_commas(MAP(elements, function(el){ |
| if (!beautify && el[0] == "atom" && el[1] == "undefined") return ""; |
| return parenthesize(el, "seq"); |
| })), "]" ]); |
| }, |
| "stat": function(stmt) { |
| return make(stmt).replace(/;*\s*$/, ";"); |
| }, |
| "seq": function() { |
| return add_commas(MAP(slice(arguments), make)); |
| }, |
| "label": function(name, block) { |
| return add_spaces([ make_name(name), ":", make(block) ]); |
| }, |
| "with": function(expr, block) { |
| return add_spaces([ "with", "(" + make(expr) + ")", make(block) ]); |
| }, |
| "atom": function(name) { |
| return make_name(name); |
| } |
| }; |
| |
| // The squeezer replaces "block"-s that contain only a single |
| // statement with the statement itself; technically, the AST |
| // is correct, but this can create problems when we output an |
| // IF having an ELSE clause where the THEN clause ends in an |
| // IF *without* an ELSE block (then the outer ELSE would refer |
| // to the inner IF). This function checks for this case and |
| // adds the block brackets if needed. |
| function make_then(th) { |
| if (th[0] == "do") { |
| // https://github.com/mishoo/UglifyJS/issues/#issue/57 |
| // IE croaks with "syntax error" on code like this: |
| // if (foo) do ... while(cond); else ... |
| // we need block brackets around do/while |
| return make([ "block", [ th ]]); |
| } |
| var b = th; |
| while (true) { |
| var type = b[0]; |
| if (type == "if") { |
| if (!b[3]) |
| // no else, we must add the block |
| return make([ "block", [ th ]]); |
| b = b[3]; |
| } |
| else if (type == "while" || type == "do") b = b[2]; |
| else if (type == "for" || type == "for-in") b = b[4]; |
| else break; |
| } |
| return make(th); |
| }; |
| |
| function make_function(name, args, body, keyword) { |
| var out = keyword || "function"; |
| if (name) { |
| out += " " + make_name(name); |
| } |
| out += "(" + add_commas(MAP(args, make_name)) + ")"; |
| return add_spaces([ out, make_block(body) ]); |
| }; |
| |
| function make_block_statements(statements) { |
| for (var a = [], last = statements.length - 1, i = 0; i <= last; ++i) { |
| var stat = statements[i]; |
| var code = make(stat); |
| if (code != ";") { |
| if (!beautify && i == last) { |
| if ((stat[0] == "while" && empty(stat[2])) || |
| (member(stat[0], [ "for", "for-in"] ) && empty(stat[4])) || |
| (stat[0] == "if" && empty(stat[2]) && !stat[3]) || |
| (stat[0] == "if" && stat[3] && empty(stat[3]))) { |
| code = code.replace(/;*\s*$/, ";"); |
| } else { |
| code = code.replace(/;+\s*$/, ""); |
| } |
| } |
| a.push(code); |
| } |
| } |
| return MAP(a, indent); |
| }; |
| |
| function make_switch_block(body) { |
| var n = body.length; |
| if (n == 0) return "{}"; |
| return "{" + newline + MAP(body, function(branch, i){ |
| var has_body = branch[1].length > 0, code = with_indent(function(){ |
| return indent(branch[0] |
| ? add_spaces([ "case", make(branch[0]) + ":" ]) |
| : "default:"); |
| }, 0.5) + (has_body ? newline + with_indent(function(){ |
| return make_block_statements(branch[1]).join(newline); |
| }) : ""); |
| if (!beautify && has_body && i < n - 1) |
| code += ";"; |
| return code; |
| }).join(newline) + newline + indent("}"); |
| }; |
| |
| function make_block(statements) { |
| if (!statements) return ";"; |
| if (statements.length == 0) return "{}"; |
| return "{" + newline + with_indent(function(){ |
| return make_block_statements(statements).join(newline); |
| }) + newline + indent("}"); |
| }; |
| |
| function make_1vardef(def) { |
| var name = def[0], val = def[1]; |
| if (val != null) |
| name = add_spaces([ make_name(name), "=", parenthesize(val, "seq") ]); |
| return name; |
| }; |
| |
| var $stack = []; |
| |
| function make(node) { |
| var type = node[0]; |
| var gen = generators[type]; |
| if (!gen) |
| throw new Error("Can't find generator for \"" + type + "\""); |
| $stack.push(node); |
| var ret = gen.apply(type, node.slice(1)); |
| $stack.pop(); |
| return ret; |
| }; |
| |
| return make(ast); |
| }; |
| |
| function split_lines(code, max_line_length) { |
| var splits = [ 0 ]; |
| jsp.parse(function(){ |
| var next_token = jsp.tokenizer(code); |
| var last_split = 0; |
| var prev_token; |
| function current_length(tok) { |
| return tok.pos - last_split; |
| }; |
| function split_here(tok) { |
| last_split = tok.pos; |
| splits.push(last_split); |
| }; |
| function custom(){ |
| var tok = next_token.apply(this, arguments); |
| out: { |
| if (prev_token) { |
| if (prev_token.type == "keyword") break out; |
| } |
| if (current_length(tok) > max_line_length) { |
| switch (tok.type) { |
| case "keyword": |
| case "atom": |
| case "name": |
| case "punc": |
| split_here(tok); |
| break out; |
| } |
| } |
| } |
| prev_token = tok; |
| return tok; |
| }; |
| custom.context = function() { |
| return next_token.context.apply(this, arguments); |
| }; |
| return custom; |
| }()); |
| return splits.map(function(pos, i){ |
| return code.substring(pos, splits[i + 1] || code.length); |
| }).join("\n"); |
| }; |
| |
| /* -----[ Utilities ]----- */ |
| |
| function repeat_string(str, i) { |
| if (i <= 0) return ""; |
| if (i == 1) return str; |
| var d = repeat_string(str, i >> 1); |
| d += d; |
| if (i & 1) d += str; |
| return d; |
| }; |
| |
| function defaults(args, defs) { |
| var ret = {}; |
| if (args === true) |
| args = {}; |
| for (var i in defs) if (HOP(defs, i)) { |
| ret[i] = (args && HOP(args, i)) ? args[i] : defs[i]; |
| } |
| return ret; |
| }; |
| |
| function is_identifier(name) { |
| return /^[a-z_$][a-z0-9_$]*$/i.test(name) |
| && name != "this" |
| && !HOP(jsp.KEYWORDS_ATOM, name) |
| && !HOP(jsp.RESERVED_WORDS, name) |
| && !HOP(jsp.KEYWORDS, name); |
| }; |
| |
| function HOP(obj, prop) { |
| return Object.prototype.hasOwnProperty.call(obj, prop); |
| }; |
| |
| // some utilities |
| |
| var MAP; |
| |
| (function(){ |
| MAP = function(a, f, o) { |
| var ret = []; |
| for (var i = 0; i < a.length; ++i) { |
| var val = f.call(o, a[i], i); |
| if (val instanceof AtTop) ret.unshift(val.v); |
| else ret.push(val); |
| } |
| return ret; |
| }; |
| MAP.at_top = function(val) { return new AtTop(val) }; |
| function AtTop(val) { this.v = val }; |
| })(); |
| |
| /* -----[ Exports ]----- */ |
| |
| exports.ast_walker = ast_walker; |
| exports.ast_mangle = ast_mangle; |
| exports.ast_squeeze = ast_squeeze; |
| exports.gen_code = gen_code; |
| exports.ast_add_scope = ast_add_scope; |
| exports.set_logger = function(logger) { warn = logger }; |
| exports.make_string = make_string; |
| exports.split_lines = split_lines; |
| exports.MAP = MAP; |
| |
| // keep this last! |
| exports.ast_squeeze_more = require("./squeeze-more").ast_squeeze_more; |
