public/assets/knockout-3-4-0/src/templating/templateRewriting.js

   1
   2 ko.templateRewriting = (function () {
   3     var memoizeDataBindingAttributeSyntaxRegex = /(<([a-z]+\d*)(?:\s+(?!data-bind\s*=\s*)[a-z0-9\-]+(?:=(?:\"[^\"]*\"|\'[^\']*\'|[^>]*))?)*\s+)data-bind\s*=\s*(["'])([\s\S]*?)\3/gi;
   4     var memoizeVirtualContainerBindingSyntaxRegex = /<!--\s*ko\b\s*([\s\S]*?)\s*-->/g;
   5
   6     function validateDataBindValuesForRewriting(keyValueArray) {
   7         var allValidators = ko.expressionRewriting.bindingRewriteValidators;
   8         for (var i = 0; i < keyValueArray.length; i++) {
   9             var key = keyValueArray[i]['key'];
  10             if (allValidators.hasOwnProperty(key)) {
  11                 var validator = allValidators[key];
  12
  13                 if (typeof validator === "function") {
  14                     var possibleErrorMessage = validator(keyValueArray[i]['value']);
  15                     if (possibleErrorMessage)
  16                         throw new Error(possibleErrorMessage);
  17                 } else if (!validator) {
  18                     throw new Error("This template engine does not support the '" + key + "' binding within its templates");
  19                 }
  20             }
  21         }
  22     }
  23
  24     function constructMemoizedTagReplacement(dataBindAttributeValue, tagToRetain, nodeName, templateEngine) {
  25         var dataBindKeyValueArray = ko.expressionRewriting.parseObjectLiteral(dataBindAttributeValue);
  26         validateDataBindValuesForRewriting(dataBindKeyValueArray);
  27         var rewrittenDataBindAttributeValue = ko.expressionRewriting.preProcessBindings(dataBindKeyValueArray, {'valueAccessors':true});
  28
  29         // For no obvious reason, Opera fails to evaluate rewrittenDataBindAttributeValue unless it's wrapped in an additional
  30         // anonymous function, even though Opera's built-in debugger can evaluate it anyway. No other browser requires this
  31         // extra indirection.
  32         var applyBindingsToNextSiblingScript =
  33             "ko.__tr_ambtns(function($context,$element){return(function(){return{ " + rewrittenDataBindAttributeValue + " } })()},'" + nodeName.toLowerCase() + "')";
  34         return templateEngine['createJavaScriptEvaluatorBlock'](applyBindingsToNextSiblingScript) + tagToRetain;
  35     }
  36
  37     return {
  38         ensureTemplateIsRewritten: function (template, templateEngine, templateDocument) {
  39             if (!templateEngine['isTemplateRewritten'](template, templateDocument))
  40                 templateEngine['rewriteTemplate'](template, function (htmlString) {
  41                     return ko.templateRewriting.memoizeBindingAttributeSyntax(htmlString, templateEngine);
  42                 }, templateDocument);
  43         },
  44
  45         memoizeBindingAttributeSyntax: function (htmlString, templateEngine) {
  46             return htmlString.replace(memoizeDataBindingAttributeSyntaxRegex, function () {
  47                 return constructMemoizedTagReplacement(/* dataBindAttributeValue: */ arguments[4], /* tagToRetain: */ arguments[1], /* nodeName: */ arguments[2], templateEngine);
  48             }).replace(memoizeVirtualContainerBindingSyntaxRegex, function() {
  49                 return constructMemoizedTagReplacement(/* dataBindAttributeValue: */ arguments[1], /* tagToRetain: */ "<!-- ko -->", /* nodeName: */ "#comment", templateEngine);
  50             });
  51         },
  52
  53         applyMemoizedBindingsToNextSibling: function (bindings, nodeName) {
  54             return ko.memoization.memoize(function (domNode, bindingContext) {
  55                 var nodeToBind = domNode.nextSibling;
  56                 if (nodeToBind && nodeToBind.nodeName.toLowerCase() === nodeName) {
  57                     ko.applyBindingAccessorsToNode(nodeToBind, bindings, bindingContext);
  58                 }
  59             });
  60         }
  61     }
  62 })();
  63
  64
  65 // Exported only because it has to be referenced by string lookup from within rewritten template
  66 ko.exportSymbol('__tr_ambtns', ko.templateRewriting.applyMemoizedBindingsToNextSibling);