fix(parser): Handle exceptions with grace

Author: jbdeboer

lib/parser.dart

@@ -161,10 +161,11 @@ getterChild(value, childKey) {
 
   InstanceMirror instanceMirror = reflect(value);
   Symbol curSym = new Symbol(childKey);
+
   try {
     // maybe it is a member field?
     return [true, instanceMirror.getField(curSym).reflectee];
-  } catch (e) {
+  } on NoSuchMethodError catch (e) {
     // maybe it is a member method?
     if (instanceMirror.type.members.containsKey(curSym)) {
       MethodMirror methodMirror = instanceMirror.type.members[curSym];
@@ -178,10 +179,16 @@ getterChild(value, childKey) {
       })];
     }
     return [false, null];
+  } catch (e) {
+    throw;
   }
 }
 
 getter(scope, locals, path) {
+  if (scope == null) {
+    return null;
+  }
+
   List<String> pathKeys = path.split('.');
   var pathKeysLength = pathKeys.length;
 

test/compiler_spec.dart

@@ -315,7 +315,7 @@ main() {
         expect(() {
           var element = $('<tab local><pane></pane><pane local></pane></tab>');
           $compile(element)(injector, element);
-        }, throwsA(contains('No provider found for LocalAttrDirective! (resolving LocalAttrDirective)')));
+        }).toThrow('No provider found for LocalAttrDirective! (resolving LocalAttrDirective)');
       }));
 
       it('should publish component controller into the scope', async(inject((Scope $rootScope) {

test/parser_spec.dart

@@ -690,6 +690,32 @@ main() {
         Parser.parse('{}()')({});
       }).toThrow('{} is not a function');
     });
+
+    it('should let null be null', () {
+      scope['map'] = {};
+
+      expect(eval('null')).toBe(null);
+      expect(eval('map.null')).toBe(null);
+    });
+
+
+    it('should behave gracefully with a null scope', () {
+      expect(Parser.parse('null')(null)).toBe(null);
+    });
+
+
+    it('should pass exceptions through getters', () {
+      expect(() {
+        Parser.parse('boo')(new ScopeWithErrors());
+      }).toThrow('boo to you');
+    });
+
+
+    it('should pass exceptions through methods', () {
+      expect(() {
+        Parser.parse('foo()')(new ScopeWithErrors());
+      }).toThrow('foo to you');
+    });
   });
 
   describe('assignable', () {
@@ -714,5 +740,9 @@ main() {
       expect(Parser.parse('a.b')({'a': {'b': 5}}, {'a': null})).toEqual(null);
     });
   });
+}
 
+class ScopeWithErrors {
+  String get boo { dump("got a boo"); throw "boo to you"; }
+  String foo() { dump("got a foo"); throw "foo to you"; }
 }