do not return 1 entry for nil values

Author: Elizabeth Lunsford

features/sizes.feature

@@ -35,4 +35,4 @@ Feature: Sizes
     When I get the JSON
     Then the JSON at "one" should have 1 entry
     And the JSON at "two" should have 2 values
-    And the JSON at "three" should have 3 numbers
+    And the JSON at "three" should have 3 numbers

lib/json_spec/matchers/have_json_size.rb

@@ -10,8 +10,12 @@ def initialize(size)
 
       def matches?(json)
         ruby = parse_json(json, @path)
-        @actual = Enumerable === ruby ? ruby.size : 1
-        @actual == @expected
+        if ruby.nil? && !@expected.nil?
+          false
+        else
+          @actual = Enumerable === ruby ? ruby.size : 1
+          @actual == @expected
+        end
       end
 
       def at_path(path)

spec/json_spec/matchers/have_json_size_spec.rb

@@ -46,4 +46,16 @@
     matcher.matches?(%({"id":1,"json":["spec"]}))
     matcher.description.should == %(have JSON size "1" at path "json")
   end
+
+  it "provides an error when parsing nil" do
+    matcher = have_json_size(0).at_path("json")
+    expect { matcher.matches?(%({"id":1,"json":null})) }.to
+      raise_error(JsonSpec::EnumerableExpected, "Enumerable expected, got nil.")
+  end
+
+  it "provides an error when parsing nil" do
+    matcher = have_json_size(0).at_path("json")
+    expect { matcher.matches?(%({"id":1,"json":12345})) }.to
+      raise_error(JsonSpec::EnumerableExpected, "Enumerable expected, got 12345.")
+  end
 end