Move the test into the proper file

Author: matthieu-foucault

test/index.spec.js

@@ -84,15 +84,4 @@ describe('immutableStateInvariantMiddleware', () => {
       dispatch({type: 'SOME_ACTION', x});
     }).toNotThrow();
   });
-
-  it('works correctly with NaN', () => {
-    const next = action => action;
-
-    const dispatch = middleware(next);
-
-    state = {foo: NaN};
-    expect(() => {
-      dispatch({type: 'SOME_ACTION'});
-    }).toNotThrow();
-  })
 });

test/trackForMutations.spec.js

@@ -226,6 +226,10 @@ describe('trackForMutations', () => {
       fn: (s) => {
         return {...s, foo: {}};
       }
+    },
+    'having a NaN in the state': {
+      getState: () => ({ a:NaN, b: Number.NaN }),
+      fn: (s) => s
     }
   };