tests/object.fy in fancy-0.6.0 vs tests/object.fy in fancy-0.7.0

@@ -169,33 +169,31 @@
         4 == 5
       }
     }
     MyClass new do_wacky_things is: false
 
-    {
-      true is: false
-    } call_with_receiver: (MyClass new)
+    @{ true is: false } call: [MyClass new]
   }
 
   it: "overrides nil" with: 'nil when: {
     class MyClass {
       def nil {
         true
       }
     }
 
-    { nil is: true } call_with_receiver: (MyClass new)
+    @{ nil is: true } call: [MyClass new]
   }
 
   it: "overrides false" with: 'false when: {
     class MyClass2 {
       def false {
         true
       }
     }
 
-    { false is: true } call_with_receiver: (MyClass2 new)
+    @{ false is: true } call: [MyClass2 new]
   }
 
   it: "implicitly sends a message to self if no receiver is specified" when: {
     def test { 42 }
     test is: 42
@@ -275,7 +273,35 @@
     }
 
     v = []
     bar: [1,2,3] values: v . is: 1
     v is: [1]
+  }
+
+  it: "provides temporarily mutable slots" with: 'with_mutable_slots: when: {
+    class Student {
+      read_slots: ('name, 'age, 'city)
+      def initialize: block {
+        with_mutable_slots: ('name, 'age, 'city) do: block
+      }
+    }
+
+    p = Student new: @{
+      name: "Chris"
+      age: 24
+      city: "Osnabrück"
+    }
+
+    p name is: "Chris"
+    p age is: 24
+    p city is: "Osnabrück"
+
+    { p name: "New Name" } raises: NoMethodError
+    { p age: 25 } raises: NoMethodError
+    { p city: "New City" } raises: NoMethodError
+
+    # no changes
+    p name is: "Chris"
+    p age is: 24
+    p city is: "Osnabrück"
   }
 }