adding Persistable#save! tests

Gemfile.lock

@@ -1,10 +1,11 @@
 PATH
   remote: .
   specs:
-    gitmodel (0.0.0)
+    gitmodel (0.0.1)
       activemodel (>= 3.0.1)
       activesupport (>= 3.0.1)
       grit (>= 2.3.0)
+      json
       lockfile (>= 1.4.3)
 
 GEM
@@ -25,6 +26,7 @@ GEM
       diff-lcs (~> 1.1)
       mime-types (~> 1.15)
     i18n (0.4.1)
+    json (1.5.1)
     lockfile (1.4.3)
     mime-types (1.16)
     rspec (2.0.1)
@@ -50,5 +52,6 @@ DEPENDENCIES
   autotest-fsevent (>= 0.2.3)
   gitmodel!
   grit (>= 2.3.0)
+  json
   lockfile (>= 1.4.3)
   rspec (>= 2.0.1)

spec/gitmodel/persistable_spec.rb

@@ -87,11 +87,26 @@ def setup
 
   describe '#save!' do
 
-    it "calls save and returns the non-false and non-nil result"
+    it "calls save and returns the non-false and non-nil result" do
+      o = TestEntity.new
+      o.should_receive(:save).and_return(o)
+
+      o.save!.should == o
+    end
+
+    it "calls save and raises an exception if the result is nil" do
+      o = TestEntity.new
+      o.should_receive(:save).and_return(nil)
 
-    it "calls save and raises an exception if the result is nil"
+      expect { o.save! }.to raise_error      
+    end
 
-    it "calls save and raises an exception if the result is false"
+    it "calls save and raises an exception if the result is false" do
+      o = TestEntity.new
+      o.should_receive(:save).and_return(false)
+
+      expect { o.save! }.to raise_error
+    end
 
   end