src/ng/compile.js

@@ -871,7 +871,7 @@ function $CompileProvider($provide, $$sanitizeUriProvider) {
   var EVENT_HANDLER_ATTR_REGEXP = /^(on[a-z]+|formaction)$/;
   var bindingCache = createMap();
 
-  function parseIsolateBindings(scope, directiveName, isController) {
+  function parseIsolateBindings(scope, directiveName, isController, validatation) {
     var LOCAL_REGEXP = /^\s*([@&<]|=(\*?))(\??)\s*(\w*)\s*$/;
 
     var bindings = createMap();
@@ -898,6 +898,9 @@ function $CompileProvider($provide, $$sanitizeUriProvider) {
         optional: match[3] === '?',
         attrName: match[4] || scopeName
       };
+      if (hasOwnProperty.call(validatation, scopeName)) {
+        bindings[scopeName].validator = validatation[scopeName];
+      }
       if (match[4]) {
         bindingCache[definition] = bindings[scopeName];
       }
@@ -914,16 +917,16 @@ function $CompileProvider($provide, $$sanitizeUriProvider) {
     if (isObject(directive.scope)) {
       if (directive.bindToController === true) {
         bindings.bindToController = parseIsolateBindings(directive.scope,
-                                                         directiveName, true);
+                                                         directiveName, true, directive.validation);
         bindings.isolateScope = {};
       } else {
         bindings.isolateScope = parseIsolateBindings(directive.scope,
-                                                     directiveName, false);
+                                                     directiveName, false, directive.validation);
       }
     }
     if (isObject(directive.bindToController)) {
       bindings.bindToController =
-          parseIsolateBindings(directive.bindToController, directiveName, true);
+          parseIsolateBindings(directive.bindToController, directiveName, true, directive.validation);
     }
     if (isObject(bindings.bindToController)) {
       var controller = directive.controller;
@@ -969,6 +972,17 @@ function $CompileProvider($provide, $$sanitizeUriProvider) {
     return require;
   }
 
+  function processDirectiveValidation($injector, validation) {
+
+    if (isArray(validation) || isFunction(validation)) {
+        validation = $injector.invoke(validation);
+    } else if (!isObject(validation)) {
+        validation = createMap(); // or should throw?
+    }
+
+    return validation;
+  }
+
   /**
    * @ngdoc method
    * @name $compileProvider#directive
@@ -1007,6 +1021,7 @@ function $CompileProvider($provide, $$sanitizeUriProvider) {
                 directive.name = directive.name || name;
                 directive.require = getDirectiveRequire(directive);
                 directive.restrict = directive.restrict || 'EA';
+                directive.validation = processDirectiveValidation($injector, directive.validation);
                 directive.$$moduleName = directiveFactory.$$moduleName;
                 directives.push(directive);
               } catch (e) {
@@ -1133,7 +1148,8 @@ function $CompileProvider($provide, $$sanitizeUriProvider) {
         scope: {},
         bindToController: options.bindings || {},
         restrict: 'E',
-        require: options.require
+        require: options.require,
+        validation: processDirectiveValidation($injector, options.validation)
       };
 
       // Copy annotations (starting with $) over to the DDO
@@ -1287,9 +1303,9 @@ function $CompileProvider($provide, $$sanitizeUriProvider) {
 
   this.$get = [
             '$injector', '$interpolate', '$exceptionHandler', '$templateRequest', '$parse',
-            '$controller', '$rootScope', '$sce', '$animate', '$$sanitizeUri',
+            '$controller', '$rootScope', '$sce', '$animate', '$$sanitizeUri', '$log',
     function($injector,   $interpolate,   $exceptionHandler,   $templateRequest,   $parse,
-             $controller,   $rootScope,   $sce,   $animate,   $$sanitizeUri) {
+             $controller,   $rootScope,   $sce,   $animate,   $$sanitizeUri,   $log) {
 
     var SIMPLE_ATTR_NAME = /^\w/;
     var specialAttrHolder = window.document.createElement('div');
@@ -3134,6 +3150,28 @@ function $CompileProvider($provide, $$sanitizeUriProvider) {
       }
     }
 
+    function checkDirectiveBindingSpec(directive, destination, validator, scopeName) {
+      // todo: check for debug mode
+
+      var error;
+
+      if (!isFunction(validator)) {
+        return;
+      }
+
+      /**
+       * Validator can throw, so application should not crash
+       */
+      try {
+        error = validator(destination, scopeName, directive.name);
+      } catch (cacthedError) {
+        error = cacthedError;
+      }
+
+      if (error instanceof Error) {
+        $log.warn('Failed scope validation:', error.message);
+      }
+    }
 
     // Set up $watches for isolate scope and controller bindings. This process
     // only occurs for isolate scopes and new scopes with controllerAs.
@@ -3145,6 +3183,7 @@ function $CompileProvider($provide, $$sanitizeUriProvider) {
         var attrName = definition.attrName,
         optional = definition.optional,
         mode = definition.mode, // @, =, or &
+        validator = definition.validator,
         lastValue,
         parentGet, parentSet, compare, removeWatch;
 
@@ -3153,12 +3192,17 @@ function $CompileProvider($provide, $$sanitizeUriProvider) {
           case '@':
             if (!optional && !hasOwnProperty.call(attrs, attrName)) {
               destination[scopeName] = attrs[attrName] = void 0;
+              checkDirectiveBindingSpec(directive, destination, validator, scopeName);
             }
             attrs.$observe(attrName, function(value) {
               if (isString(value) || isBoolean(value)) {
                 var oldValue = destination[scopeName];
                 recordChanges(scopeName, value, oldValue);
                 destination[scopeName] = value;
+
+                if (oldValue !== value) {
+                    checkDirectiveBindingSpec(directive, destination, validator, scopeName);
+                }
               }
             });
             attrs.$$observers[attrName].$$scope = scope;
@@ -3172,6 +3216,12 @@ function $CompileProvider($provide, $$sanitizeUriProvider) {
               // the value to boolean rather than a string, so we special case this situation
               destination[scopeName] = lastValue;
             }
+
+            // Should it be called before SimpleChange?
+            if (!optional || (optional && hasOwnProperty.call(attrs, attrName))) {
+                checkDirectiveBindingSpec(directive, destination, validator, scopeName);
+            }
+
             initialChanges[scopeName] = new SimpleChange(_UNINITIALIZED_VALUE, destination[scopeName]);
             break;
 
@@ -3196,6 +3246,8 @@ function $CompileProvider($provide, $$sanitizeUriProvider) {
                   attrs[attrName], attrName, directive.name);
             };
             lastValue = destination[scopeName] = parentGet(scope);
+            checkDirectiveBindingSpec(directive, destination, validator, scopeName);
+
             var parentValueWatch = function parentValueWatch(parentValue) {
               if (!compare(parentValue, destination[scopeName])) {
                 // we are out of sync and need to copy
@@ -3206,6 +3258,7 @@ function $CompileProvider($provide, $$sanitizeUriProvider) {
                   // if the parent can be assigned then do so
                   parentSet(scope, parentValue = destination[scopeName]);
                 }
+                checkDirectiveBindingSpec(directive, destination, validator, scopeName);
               }
               return lastValue = parentValue;
             };
@@ -3228,6 +3281,7 @@ function $CompileProvider($provide, $$sanitizeUriProvider) {
             parentGet = $parse(attrs[attrName]);
 
             var initialValue = destination[scopeName] = parentGet(scope);
+            checkDirectiveBindingSpec(directive, destination, validator, scopeName); // Should it be called before SimpleChange?
             initialChanges[scopeName] = new SimpleChange(_UNINITIALIZED_VALUE, destination[scopeName]);
 
             removeWatch = scope.$watch(parentGet, function parentValueWatchAction(newValue, oldValue) {
@@ -3237,6 +3291,7 @@ function $CompileProvider($provide, $$sanitizeUriProvider) {
               }
               recordChanges(scopeName, newValue, oldValue);
               destination[scopeName] = newValue;
+              checkDirectiveBindingSpec(directive, destination, validator, scopeName);
             }, parentGet.literal);
 
             removeWatchCollection.push(removeWatch);
@@ -3249,6 +3304,10 @@ function $CompileProvider($provide, $$sanitizeUriProvider) {
             // Don't assign noop to destination if expression is not valid
             if (parentGet === noop && optional) break;
 
+            // What should be checked here?
+            // If can't check result of the expression, because we can't be sure that the expression is idempotent.
+            // By now let just leave `&` binding
+
             destination[scopeName] = function(locals) {
               return parentGet(scope, locals);
             };