Index: chrome/third_party/jstemplate/jsevalcontext.js |
=================================================================== |
--- chrome/third_party/jstemplate/jsevalcontext.js (revision 177458) |
+++ chrome/third_party/jstemplate/jsevalcontext.js (working copy) |
@@ -1,409 +0,0 @@ |
-// Copyright 2006 Google Inc. |
-// |
-// Licensed under the Apache License, Version 2.0 (the "License"); |
-// you may not use this file except in compliance with the License. |
-// You may obtain a copy of the License at |
-// |
-// http://www.apache.org/licenses/LICENSE-2.0 |
-// |
-// Unless required by applicable law or agreed to in writing, software |
-// distributed under the License is distributed on an "AS IS" BASIS, |
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or |
-// implied. See the License for the specific language governing |
-// permissions and limitations under the License. |
-/** |
- * Author: Steffen Meschkat <mesch@google.com> |
- * |
- * @fileoverview This class is used to evaluate expressions in a local |
- * context. Used by JstProcessor. |
- */ |
- |
- |
-/** |
- * Names of special variables defined by the jstemplate evaluation |
- * context. These can be used in js expression in jstemplate |
- * attributes. |
- */ |
-var VAR_index = '$index'; |
-var VAR_count = '$count'; |
-var VAR_this = '$this'; |
-var VAR_context = '$context'; |
-var VAR_top = '$top'; |
- |
- |
-/** |
- * The name of the global variable which holds the value to be returned if |
- * context evaluation results in an error. |
- * Use JsEvalContext.setGlobal(GLOB_default, value) to set this. |
- */ |
-var GLOB_default = '$default'; |
- |
- |
-/** |
- * Un-inlined literals, to avoid object creation in IE6. TODO(mesch): |
- * So far, these are only used here, but we could use them thoughout |
- * the code and thus move them to constants.js. |
- */ |
-var CHAR_colon = ':'; |
-var REGEXP_semicolon = /\s*;\s*/; |
- |
- |
-/** |
- * See constructor_() |
- * @param {Object|null} opt_data |
- * @param {Object} opt_parent |
- * @constructor |
- */ |
-function JsEvalContext(opt_data, opt_parent) { |
- this.constructor_.apply(this, arguments); |
-} |
- |
-/** |
- * Context for processing a jstemplate. The context contains a context |
- * object, whose properties can be referred to in jstemplate |
- * expressions, and it holds the locally defined variables. |
- * |
- * @param {Object|null} opt_data The context object. Null if no context. |
- * |
- * @param {Object} opt_parent The parent context, from which local |
- * variables are inherited. Normally the context object of the parent |
- * context is the object whose property the parent object is. Null for the |
- * context of the root object. |
- */ |
-JsEvalContext.prototype.constructor_ = function(opt_data, opt_parent) { |
- var me = this; |
- |
- /** |
- * The context for variable definitions in which the jstemplate |
- * expressions are evaluated. Other than for the local context, |
- * which replaces the parent context, variable definitions of the |
- * parent are inherited. The special variable $this points to data_. |
- * |
- * If this instance is recycled from the cache, then the property is |
- * already initialized. |
- * |
- * @type {Object} |
- */ |
- if (!me.vars_) { |
- me.vars_ = {}; |
- } |
- if (opt_parent) { |
- // If there is a parent node, inherit local variables from the |
- // parent. |
- copyProperties(me.vars_, opt_parent.vars_); |
- } else { |
- // If a root node, inherit global symbols. Since every parent |
- // chain has a root with no parent, global variables will be |
- // present in the case above too. This means that globals can be |
- // overridden by locals, as it should be. |
- copyProperties(me.vars_, JsEvalContext.globals_); |
- } |
- |
- /** |
- * The current context object is assigned to the special variable |
- * $this so it is possible to use it in expressions. |
- * @type Object |
- */ |
- me.vars_[VAR_this] = opt_data; |
- |
- /** |
- * The entire context structure is exposed as a variable so it can be |
- * passed to javascript invocations through jseval. |
- */ |
- me.vars_[VAR_context] = me; |
- |
- /** |
- * The local context of the input data in which the jstemplate |
- * expressions are evaluated. Notice that this is usually an Object, |
- * but it can also be a scalar value (and then still the expression |
- * $this can be used to refer to it). Notice this can even be value, |
- * undefined or null. Hence, we have to protect jsexec() from using |
- * undefined or null, yet we want $this to reflect the true value of |
- * the current context. Thus we assign the original value to $this, |
- * above, but for the expression context we replace null and |
- * undefined by the empty string. |
- * |
- * @type {Object|null} |
- */ |
- me.data_ = getDefaultObject(opt_data, STRING_empty); |
- |
- if (!opt_parent) { |
- // If this is a top-level context, create a variable reference to the data |
- // to allow for accessing top-level properties of the original context |
- // data from child contexts. |
- me.vars_[VAR_top] = me.data_; |
- } |
-}; |
- |
- |
-/** |
- * A map of globally defined symbols. Every instance of JsExprContext |
- * inherits them in its vars_. |
- * @type Object |
- */ |
-JsEvalContext.globals_ = {} |
- |
- |
-/** |
- * Sets a global symbol. It will be available like a variable in every |
- * JsEvalContext instance. This is intended mainly to register |
- * immutable global objects, such as functions, at load time, and not |
- * to add global data at runtime. I.e. the same objections as to |
- * global variables in general apply also here. (Hence the name |
- * "global", and not "global var".) |
- * @param {string} name |
- * @param {Object|null} value |
- */ |
-JsEvalContext.setGlobal = function(name, value) { |
- JsEvalContext.globals_[name] = value; |
-}; |
- |
- |
-/** |
- * Set the default value to be returned if context evaluation results in an |
- * error. (This can occur if a non-existent value was requested). |
- */ |
-JsEvalContext.setGlobal(GLOB_default, null); |
- |
- |
-/** |
- * A cache to reuse JsEvalContext instances. (IE6 perf) |
- * |
- * @type Array.<JsEvalContext> |
- */ |
-JsEvalContext.recycledInstances_ = []; |
- |
- |
-/** |
- * A factory to create a JsEvalContext instance, possibly reusing |
- * one from recycledInstances_. (IE6 perf) |
- * |
- * @param {Object} opt_data |
- * @param {JsEvalContext} opt_parent |
- * @return {JsEvalContext} |
- */ |
-JsEvalContext.create = function(opt_data, opt_parent) { |
- if (jsLength(JsEvalContext.recycledInstances_) > 0) { |
- var instance = JsEvalContext.recycledInstances_.pop(); |
- JsEvalContext.call(instance, opt_data, opt_parent); |
- return instance; |
- } else { |
- return new JsEvalContext(opt_data, opt_parent); |
- } |
-}; |
- |
- |
-/** |
- * Recycle a used JsEvalContext instance, so we can avoid creating one |
- * the next time we need one. (IE6 perf) |
- * |
- * @param {JsEvalContext} instance |
- */ |
-JsEvalContext.recycle = function(instance) { |
- for (var i in instance.vars_) { |
- // NOTE(mesch): We avoid object creation here. (IE6 perf) |
- delete instance.vars_[i]; |
- } |
- instance.data_ = null; |
- JsEvalContext.recycledInstances_.push(instance); |
-}; |
- |
- |
-/** |
- * Executes a function created using jsEvalToFunction() in the context |
- * of vars, data, and template. |
- * |
- * @param {Function} exprFunction A javascript function created from |
- * a jstemplate attribute value. |
- * |
- * @param {Element} template DOM node of the template. |
- * |
- * @return {Object|null} The value of the expression from which |
- * exprFunction was created in the current js expression context and |
- * the context of template. |
- */ |
-JsEvalContext.prototype.jsexec = function(exprFunction, template) { |
- try { |
- return exprFunction.call(template, this.vars_, this.data_); |
- } catch (e) { |
- log('jsexec EXCEPTION: ' + e + ' at ' + template + |
- ' with ' + exprFunction); |
- return JsEvalContext.globals_[GLOB_default]; |
- } |
-}; |
- |
- |
-/** |
- * Clones the current context for a new context object. The cloned |
- * context has the data object as its context object and the current |
- * context as its parent context. It also sets the $index variable to |
- * the given value. This value usually is the position of the data |
- * object in a list for which a template is instantiated multiply. |
- * |
- * @param {Object} data The new context object. |
- * |
- * @param {number} index Position of the new context when multiply |
- * instantiated. (See implementation of jstSelect().) |
- * |
- * @param {number} count The total number of contexts that were multiply |
- * instantiated. (See implementation of jstSelect().) |
- * |
- * @return {JsEvalContext} |
- */ |
-JsEvalContext.prototype.clone = function(data, index, count) { |
- var ret = JsEvalContext.create(data, this); |
- ret.setVariable(VAR_index, index); |
- ret.setVariable(VAR_count, count); |
- return ret; |
-}; |
- |
- |
-/** |
- * Binds a local variable to the given value. If set from jstemplate |
- * jsvalue expressions, variable names must start with $, but in the |
- * API they only have to be valid javascript identifier. |
- * |
- * @param {string} name |
- * |
- * @param {Object?} value |
- */ |
-JsEvalContext.prototype.setVariable = function(name, value) { |
- this.vars_[name] = value; |
-}; |
- |
- |
-/** |
- * Returns the value bound to the local variable of the given name, or |
- * undefined if it wasn't set. There is no way to distinguish a |
- * variable that wasn't set from a variable that was set to |
- * undefined. Used mostly for testing. |
- * |
- * @param {string} name |
- * |
- * @return {Object?} value |
- */ |
-JsEvalContext.prototype.getVariable = function(name) { |
- return this.vars_[name]; |
-}; |
- |
- |
-/** |
- * Evaluates a string expression within the scope of this context |
- * and returns the result. |
- * |
- * @param {string} expr A javascript expression |
- * @param {Element} opt_template An optional node to serve as "this" |
- * |
- * @return {Object?} value |
- */ |
-JsEvalContext.prototype.evalExpression = function(expr, opt_template) { |
- var exprFunction = jsEvalToFunction(expr); |
- return this.jsexec(exprFunction, opt_template); |
-}; |
- |
- |
-/** |
- * Uninlined string literals for jsEvalToFunction() (IE6 perf). |
- */ |
-var STRING_a = 'a_'; |
-var STRING_b = 'b_'; |
-var STRING_with = 'with (a_) with (b_) return '; |
- |
- |
-/** |
- * Cache for jsEvalToFunction results. |
- * @type Object |
- */ |
-JsEvalContext.evalToFunctionCache_ = {}; |
- |
- |
-/** |
- * Evaluates the given expression as the body of a function that takes |
- * vars and data as arguments. Since the resulting function depends |
- * only on expr, we cache the result so we save some Function |
- * invocations, and some object creations in IE6. |
- * |
- * @param {string} expr A javascript expression. |
- * |
- * @return {Function} A function that returns the value of expr in the |
- * context of vars and data. |
- */ |
-function jsEvalToFunction(expr) { |
- if (!JsEvalContext.evalToFunctionCache_[expr]) { |
- try { |
- // NOTE(mesch): The Function constructor is faster than eval(). |
- JsEvalContext.evalToFunctionCache_[expr] = |
- new Function(STRING_a, STRING_b, STRING_with + expr); |
- } catch (e) { |
- log('jsEvalToFunction (' + expr + ') EXCEPTION ' + e); |
- } |
- } |
- return JsEvalContext.evalToFunctionCache_[expr]; |
-} |
- |
- |
-/** |
- * Evaluates the given expression to itself. This is meant to pass |
- * through string attribute values. |
- * |
- * @param {string} expr |
- * |
- * @return {string} |
- */ |
-function jsEvalToSelf(expr) { |
- return expr; |
-} |
- |
- |
-/** |
- * Parses the value of the jsvalues attribute in jstemplates: splits |
- * it up into a map of labels and expressions, and creates functions |
- * from the expressions that are suitable for execution by |
- * JsEvalContext.jsexec(). All that is returned as a flattened array |
- * of pairs of a String and a Function. |
- * |
- * @param {string} expr |
- * |
- * @return {Array} |
- */ |
-function jsEvalToValues(expr) { |
- // TODO(mesch): It is insufficient to split the values by simply |
- // finding semi-colons, as the semi-colon may be part of a string |
- // constant or escaped. |
- var ret = []; |
- var values = expr.split(REGEXP_semicolon); |
- for (var i = 0, I = jsLength(values); i < I; ++i) { |
- var colon = values[i].indexOf(CHAR_colon); |
- if (colon < 0) { |
- continue; |
- } |
- var label = stringTrim(values[i].substr(0, colon)); |
- var value = jsEvalToFunction(values[i].substr(colon + 1)); |
- ret.push(label, value); |
- } |
- return ret; |
-} |
- |
- |
-/** |
- * Parses the value of the jseval attribute of jstemplates: splits it |
- * up into a list of expressions, and creates functions from the |
- * expressions that are suitable for execution by |
- * JsEvalContext.jsexec(). All that is returned as an Array of |
- * Function. |
- * |
- * @param {string} expr |
- * |
- * @return {Array.<Function>} |
- */ |
-function jsEvalToExpressions(expr) { |
- var ret = []; |
- var values = expr.split(REGEXP_semicolon); |
- for (var i = 0, I = jsLength(values); i < I; ++i) { |
- if (values[i]) { |
- var value = jsEvalToFunction(values[i]); |
- ret.push(value); |
- } |
- } |
- return ret; |
-} |