diff --git a/src/addons/transitions/__tests__/ReactCSSTransitionGroup-test.js b/src/addons/transitions/__tests__/ReactCSSTransitionGroup-test.js
index dabd3c5819..3c08014110 100644
--- a/src/addons/transitions/__tests__/ReactCSSTransitionGroup-test.js
+++ b/src/addons/transitions/__tests__/ReactCSSTransitionGroup-test.js
@@ -26,6 +26,7 @@ describe('ReactCSSTransitionGroup', function() {
     mocks = require('mocks');
 
     container = document.createElement('div');
+    spyOn(console, 'warn');
   });
 
   it('should warn after time with no transitionend', function() {
@@ -49,8 +50,6 @@ describe('ReactCSSTransitionGroup', function() {
     expect(a.getDOMNode().childNodes[0].id).toBe('two');
     expect(a.getDOMNode().childNodes[1].id).toBe('one');
 
-    console.warn = mocks.getMockFunction();
-
     // For some reason jst is adding extra setTimeout()s and grunt test isn't,
     // so we need to do this disgusting hack.
     for (var i = 0 ; i < setTimeout.mock.calls.length; i++) {
@@ -61,7 +60,7 @@ describe('ReactCSSTransitionGroup', function() {
     }
 
     expect(a.getDOMNode().childNodes.length).toBe(2);
-    expect(console.warn.mock.calls.length).toBe(1);
+    expect(console.warn.argsForCall.length).toBe(1);
   });
 
   it('should keep both sets of DOM nodes around', function() {
diff --git a/src/browser/server/__tests__/ReactServerRendering-test.js b/src/browser/server/__tests__/ReactServerRendering-test.js
index cee8ba19e8..50b03234af 100644
--- a/src/browser/server/__tests__/ReactServerRendering-test.js
+++ b/src/browser/server/__tests__/ReactServerRendering-test.js
@@ -48,6 +48,7 @@ describe('ReactServerRendering', function() {
 
     var DOMProperty = require('DOMProperty');
     ID_ATTRIBUTE_NAME = DOMProperty.ID_ATTRIBUTE_NAME;
+    spyOn(console, 'warn');
   });
 
   describe('renderToString', function() {
@@ -215,15 +216,12 @@ describe('ReactServerRendering', function() {
 
       // Now simulate a situation where the app is not idempotent. React should
       // warn but do the right thing.
-      var _warn = console.warn;
-      console.warn = mocks.getMockFunction();
       element.innerHTML = lastMarkup;
       var instance = React.render(<TestComponent name="y" />, element);
       expect(mountCount).toEqual(4);
-      expect(console.warn.mock.calls.length).toBe(1);
+      expect(console.warn.argsForCall.length).toBe(1);
       expect(element.innerHTML.length > 0).toBe(true);
       expect(element.innerHTML).not.toEqual(lastMarkup);
-      console.warn = _warn;
 
       // Ensure the events system works
       expect(numClicks).toEqual(0);
diff --git a/src/browser/ui/dom/components/__tests__/ReactDOMInput-test.js b/src/browser/ui/dom/components/__tests__/ReactDOMInput-test.js
index b20f3b60a2..ae1f3777f5 100644
--- a/src/browser/ui/dom/components/__tests__/ReactDOMInput-test.js
+++ b/src/browser/ui/dom/components/__tests__/ReactDOMInput-test.js
@@ -25,6 +25,7 @@ describe('ReactDOMInput', function() {
     React = require('React');
     ReactLink = require('ReactLink');
     ReactTestUtils = require('ReactTestUtils');
+    spyOn(console, 'warn');
   });
 
   it('should display `defaultValue` of number 0', function() {
@@ -212,42 +213,28 @@ describe('ReactDOMInput', function() {
   });
 
   it('should warn with value and no onChange handler', function() {
-    var oldWarn = console.warn;
-    try {
-      console.warn = mocks.getMockFunction();
+    var link = new ReactLink('yolo', mocks.getMockFunction());
+    ReactTestUtils.renderIntoDocument(<input type="text" valueLink={link} />);
+    expect(console.warn.argsForCall.length).toBe(0);
 
-      var link = new ReactLink('yolo', mocks.getMockFunction());
-      ReactTestUtils.renderIntoDocument(<input type="text" valueLink={link} />);
-      expect(console.warn.mock.calls.length).toBe(0);
-
-      ReactTestUtils.renderIntoDocument(
-        <input type="text" value="zoink" onChange={mocks.getMockFunction()} />
-      );
-      expect(console.warn.mock.calls.length).toBe(0);
-      ReactTestUtils.renderIntoDocument(<input type="text" value="zoink" />);
-      expect(console.warn.mock.calls.length).toBe(1);
-    } finally {
-      console.warn = oldWarn;
-    }
+    ReactTestUtils.renderIntoDocument(
+      <input type="text" value="zoink" onChange={mocks.getMockFunction()} />
+    );
+    expect(console.warn.argsForCall.length).toBe(0);
+    ReactTestUtils.renderIntoDocument(<input type="text" value="zoink" />);
+    expect(console.warn.argsForCall.length).toBe(1);
   });
 
   it('should warn with value and no onChange handler and readOnly specified', function() {
-    var oldWarn = console.warn;
-    try {
-      console.warn = mocks.getMockFunction();
+    ReactTestUtils.renderIntoDocument(
+      <input type="text" value="zoink" readOnly={true} />
+    );
+    expect(console.warn.argsForCall.length).toBe(0);
 
-      ReactTestUtils.renderIntoDocument(
-        <input type="text" value="zoink" readOnly={true} />
-      );
-      expect(console.warn.mock.calls.length).toBe(0);
-
-      ReactTestUtils.renderIntoDocument(
-        <input type="text" value="zoink" readOnly={false} />
-      );
-      expect(console.warn.mock.calls.length).toBe(1);
-    } finally {
-      console.warn = oldWarn;
-    }
+    ReactTestUtils.renderIntoDocument(
+      <input type="text" value="zoink" readOnly={false} />
+    );
+    expect(console.warn.argsForCall.length).toBe(1);
   });
 
   it('should throw if both value and valueLink are provided', function() {
@@ -294,53 +281,39 @@ describe('ReactDOMInput', function() {
   });
 
   it('should warn with checked and no onChange handler', function() {
-    var oldWarn = console.warn;
-    try {
-      console.warn = mocks.getMockFunction();
+    var node = document.createElement('div');
+    var link = new ReactLink(true, mocks.getMockFunction());
+    React.render(<input type="checkbox" checkedLink={link} />, node);
+    expect(console.warn.argsForCall.length).toBe(0);
 
-      var node = document.createElement('div');
-      var link = new ReactLink(true, mocks.getMockFunction());
-      React.render(<input type="checkbox" checkedLink={link} />, node);
-      expect(console.warn.mock.calls.length).toBe(0);
+    ReactTestUtils.renderIntoDocument(
+      <input
+        type="checkbox"
+        checked="false"
+        onChange={mocks.getMockFunction()}
+      />
+    );
+    expect(console.warn.argsForCall.length).toBe(0);
 
-      ReactTestUtils.renderIntoDocument(
-        <input
-          type="checkbox"
-          checked="false"
-          onChange={mocks.getMockFunction()}
-        />
-      );
-      expect(console.warn.mock.calls.length).toBe(0);
+    ReactTestUtils.renderIntoDocument(
+      <input type="checkbox" checked="false" readOnly={true} />
+    );
+    expect(console.warn.argsForCall.length).toBe(0);
 
-      ReactTestUtils.renderIntoDocument(
-        <input type="checkbox" checked="false" readOnly={true} />
-      );
-      expect(console.warn.mock.calls.length).toBe(0);
-
-      ReactTestUtils.renderIntoDocument(<input type="checkbox" checked="false" />);
-      expect(console.warn.mock.calls.length).toBe(1);
-    } finally {
-      console.warn = oldWarn;
-    }
+    ReactTestUtils.renderIntoDocument(<input type="checkbox" checked="false" />);
+    expect(console.warn.argsForCall.length).toBe(1);
   });
 
   it('should warn with checked and no onChange handler with readOnly specified', function() {
-    var oldWarn = console.warn;
-    try {
-      console.warn = mocks.getMockFunction();
+    ReactTestUtils.renderIntoDocument(
+      <input type="checkbox" checked="false" readOnly={true} />
+    );
+    expect(console.warn.argsForCall.length).toBe(0);
 
-      ReactTestUtils.renderIntoDocument(
-        <input type="checkbox" checked="false" readOnly={true} />
-      );
-      expect(console.warn.mock.calls.length).toBe(0);
-
-      ReactTestUtils.renderIntoDocument(
-        <input type="checkbox" checked="false" readOnly={false} />
-      );
-      expect(console.warn.mock.calls.length).toBe(1);
-    } finally {
-      console.warn = oldWarn;
-    }
+    ReactTestUtils.renderIntoDocument(
+      <input type="checkbox" checked="false" readOnly={false} />
+    );
+    expect(console.warn.argsForCall.length).toBe(1);
   });
 
   it('should throw if both checked and checkedLink are provided', function() {
diff --git a/src/classic/__tests__/ReactContextValidator-test.js b/src/classic/__tests__/ReactContextValidator-test.js
index bc504a3531..097d8ad99f 100644
--- a/src/classic/__tests__/ReactContextValidator-test.js
+++ b/src/classic/__tests__/ReactContextValidator-test.js
@@ -32,7 +32,7 @@ describe('ReactContextValidator', function() {
     reactComponentExpect = require('reactComponentExpect');
     mocks = require('mocks');
 
-    console.warn = mocks.getMockFunction();
+    spyOn(console, 'warn');
   });
 
   // TODO: This behavior creates a runtime dependency on propTypes. We should
@@ -145,8 +145,8 @@ describe('ReactContextValidator', function() {
 
     ReactTestUtils.renderIntoDocument(<Component />);
 
-    expect(console.warn.mock.calls.length).toBe(1);
-    expect(console.warn.mock.calls[0][0]).toBe(
+    expect(console.warn.argsForCall.length).toBe(1);
+    expect(console.warn.argsForCall[0][0]).toBe(
       'Warning: Required context `foo` was not specified in `Component`.'
     );
 
@@ -171,7 +171,7 @@ describe('ReactContextValidator', function() {
     );
 
     // Previous call should not error
-    expect(console.warn.mock.calls.length).toBe(1);
+    expect(console.warn.argsForCall.length).toBe(1);
 
     var ComponentInFooNumberContext = React.createClass({
       childContextTypes: {
@@ -191,8 +191,8 @@ describe('ReactContextValidator', function() {
 
     ReactTestUtils.renderIntoDocument(<ComponentInFooNumberContext fooValue={123} />);
 
-    expect(console.warn.mock.calls.length).toBe(2);
-    expect(console.warn.mock.calls[1][0]).toBe(
+    expect(console.warn.argsForCall.length).toBe(2);
+    expect(console.warn.argsForCall[1][0]).toBe(
       'Warning: Invalid context `foo` of type `number` supplied ' +
       'to `Component`, expected `string`.' +
       ' Check the render method of `ComponentInFooNumberContext`.'
@@ -216,18 +216,18 @@ describe('ReactContextValidator', function() {
     });
 
     ReactTestUtils.renderIntoDocument(<Component testContext={{bar: 123}} />);
-    expect(console.warn.mock.calls.length).toBe(2);
-    expect(console.warn.mock.calls[0][0]).toBe(
+    expect(console.warn.argsForCall.length).toBe(2);
+    expect(console.warn.argsForCall[0][0]).toBe(
       'Warning: Required child context `foo` was not specified in `Component`.'
     );
-    expect(console.warn.mock.calls[1][0]).toBe(
+    expect(console.warn.argsForCall[1][0]).toBe(
       'Warning: Required child context `foo` was not specified in `Component`.'
     );
 
     ReactTestUtils.renderIntoDocument(<Component testContext={{foo: 123}} />);
 
-    expect(console.warn.mock.calls.length).toBe(4);
-    expect(console.warn.mock.calls[3][0]).toBe(
+    expect(console.warn.argsForCall.length).toBe(4);
+    expect(console.warn.argsForCall[3][0]).toBe(
       'Warning: Invalid child context `foo` of type `number` ' +
       'supplied to `Component`, expected `string`.'
     );
@@ -241,7 +241,7 @@ describe('ReactContextValidator', function() {
     );
 
     // Previous calls should not log errors
-    expect(console.warn.mock.calls.length).toBe(4);
+    expect(console.warn.argsForCall.length).toBe(4);
   });
 
 });
diff --git a/src/classic/class/__tests__/ReactClass-test.js b/src/classic/class/__tests__/ReactClass-test.js
index b0d3b45b5a..64543e6c60 100644
--- a/src/classic/class/__tests__/ReactClass-test.js
+++ b/src/classic/class/__tests__/ReactClass-test.js
@@ -21,6 +21,7 @@ describe('ReactClass-spec', function() {
   beforeEach(function() {
     React = require('React');
     ReactTestUtils = require('ReactTestUtils');
+    spyOn(console, 'warn');
   });
 
   it('should throw when `render` is not specified', function() {
@@ -49,10 +50,9 @@ describe('ReactClass-spec', function() {
         return <div />;
       }
     });
-    console.warn = mocks.getMockFunction();
     expect(TestComponent.type).toBe(TestComponent);
-    expect(console.warn.mock.calls.length).toBe(1);
-    expect(console.warn.mock.calls[0][0]).toBe(
+    expect(console.warn.argsForCall.length).toBe(1);
+    expect(console.warn.argsForCall[0][0]).toBe(
       'Warning: TestComponent.type is deprecated. Use TestComponent ' +
       'directly to access the class.'
     );
@@ -126,44 +126,37 @@ describe('ReactClass-spec', function() {
   });
 
   it('should warn when mispelling shouldComponentUpdate', function() {
-    var warn = console.warn;
-    console.warn = mocks.getMockFunction();
+    React.createClass({
+      componentShouldUpdate: function() {
+        return false;
+      },
+      render: function() {
+        return <div />;
+      }
+    });
+    expect(console.warn.argsForCall.length).toBe(1);
+    expect(console.warn.argsForCall[0][0]).toBe(
+      'A component has a method called componentShouldUpdate(). Did you ' +
+      'mean shouldComponentUpdate()? The name is phrased as a question ' +
+      'because the function is expected to return a value.'
+    );
 
-    try {
-      React.createClass({
-        componentShouldUpdate: function() {
-          return false;
-        },
-        render: function() {
-          return <div />;
-        }
-      });
-      expect(console.warn.mock.calls.length).toBe(1);
-      expect(console.warn.mock.calls[0][0]).toBe(
-        'A component has a method called componentShouldUpdate(). Did you ' +
-        'mean shouldComponentUpdate()? The name is phrased as a question ' +
-        'because the function is expected to return a value.'
-      );
+    var NamedComponent = React.createClass({
+      componentShouldUpdate: function() {
+        return false;
+      },
+      render: function() {
+        return <div />;
+      }
+    });
+    expect(console.warn.argsForCall.length).toBe(2);
+    expect(console.warn.argsForCall[1][0]).toBe(
+      'NamedComponent has a method called componentShouldUpdate(). Did you ' +
+      'mean shouldComponentUpdate()? The name is phrased as a question ' +
+      'because the function is expected to return a value.'
+    );
 
-      var NamedComponent = React.createClass({
-        componentShouldUpdate: function() {
-          return false;
-        },
-        render: function() {
-          return <div />;
-        }
-      });
-      expect(console.warn.mock.calls.length).toBe(2);
-      expect(console.warn.mock.calls[1][0]).toBe(
-        'NamedComponent has a method called componentShouldUpdate(). Did you ' +
-        'mean shouldComponentUpdate()? The name is phrased as a question ' +
-        'because the function is expected to return a value.'
-      );
-
-      <NamedComponent />; // Shut up lint
-    } finally {
-      console.warn = warn;
-    }
+    <NamedComponent />; // Shut up lint
   });
 
   it('should throw if a reserved property is in statics', function() {
@@ -192,44 +185,38 @@ describe('ReactClass-spec', function() {
   // TODO: Consider actually moving these to statics or drop this unit test.
 
   xit('should warn when using deprecated non-static spec keys', function() {
-    var warn = console.warn;
-    console.warn = mocks.getMockFunction();
-    try {
-      React.createClass({
-        mixins: [{}],
-        propTypes: {
-          foo: React.PropTypes.string
-        },
-        contextTypes: {
-          foo: React.PropTypes.string
-        },
-        childContextTypes: {
-          foo: React.PropTypes.string
-        },
-        render: function() {
-          return <div />;
-        }
-      });
-      expect(console.warn.mock.calls.length).toBe(4);
-      expect(console.warn.mock.calls[0][0]).toBe(
-        'createClass(...): `mixins` is now a static property and should ' +
-        'be defined inside "statics".'
-      );
-      expect(console.warn.mock.calls[1][0]).toBe(
-        'createClass(...): `propTypes` is now a static property and should ' +
-        'be defined inside "statics".'
-      );
-      expect(console.warn.mock.calls[2][0]).toBe(
-        'createClass(...): `contextTypes` is now a static property and ' +
-        'should be defined inside "statics".'
-      );
-      expect(console.warn.mock.calls[3][0]).toBe(
-        'createClass(...): `childContextTypes` is now a static property and ' +
-        'should be defined inside "statics".'
-      );
-    } finally {
-      console.warn = warn;
-    }
+    React.createClass({
+      mixins: [{}],
+      propTypes: {
+        foo: React.PropTypes.string
+      },
+      contextTypes: {
+        foo: React.PropTypes.string
+      },
+      childContextTypes: {
+        foo: React.PropTypes.string
+      },
+      render: function() {
+        return <div />;
+      }
+    });
+    expect(console.warn.argsForCall.length).toBe(4);
+    expect(console.warn.argsForCall[0][0]).toBe(
+      'createClass(...): `mixins` is now a static property and should ' +
+      'be defined inside "statics".'
+    );
+    expect(console.warn.argsForCall[1][0]).toBe(
+      'createClass(...): `propTypes` is now a static property and should ' +
+      'be defined inside "statics".'
+    );
+    expect(console.warn.argsForCall[2][0]).toBe(
+      'createClass(...): `contextTypes` is now a static property and ' +
+      'should be defined inside "statics".'
+    );
+    expect(console.warn.argsForCall[3][0]).toBe(
+      'createClass(...): `childContextTypes` is now a static property and ' +
+      'should be defined inside "statics".'
+    );
   });
 
   it('should support statics', function() {
diff --git a/src/core/__tests__/ReactCompositeComponent-test.js b/src/core/__tests__/ReactCompositeComponent-test.js
index ee705d4e2f..c01444cea5 100644
--- a/src/core/__tests__/ReactCompositeComponent-test.js
+++ b/src/core/__tests__/ReactCompositeComponent-test.js
@@ -24,8 +24,6 @@ var ReactTestUtils;
 var cx;
 var reactComponentExpect;
 var mocks;
-var warn;
-
 
 describe('ReactCompositeComponent', function() {
 
@@ -75,12 +73,7 @@ describe('ReactCompositeComponent', function() {
       }
     });
 
-    warn = console.warn;
-    console.warn = mocks.getMockFunction();
-  });
-
-  afterEach(function() {
-    console.warn = warn;
+    spyOn(console, 'warn');
   });
 
   it('should support rendering to different child types over time', function() {
@@ -118,7 +111,6 @@ describe('ReactCompositeComponent', function() {
     var container = document.createElement('div');
     container.innerHTML = markup;
 
-    spyOn(console, 'warn');
     React.render(<Parent />, container);
     expect(console.warn).not.toHaveBeenCalled();
   });
@@ -161,8 +153,6 @@ describe('ReactCompositeComponent', function() {
   });
 
   it('should auto bind methods and values correctly', function() {
-    spyOn(console, 'warn');
-
     var ComponentClass = React.createClass({
       getInitialState: function() {
         return {valueToReturn: 'hi'};
@@ -470,35 +460,28 @@ describe('ReactCompositeComponent', function() {
   });
 
   it('should warn when shouldComponentUpdate() returns undefined', function() {
-    var warn = console.warn;
-    console.warn = mocks.getMockFunction();
+    var Component = React.createClass({
+      getInitialState: function () {
+        return {bogus: false};
+      },
 
-    try {
-      var Component = React.createClass({
-        getInitialState: function () {
-          return {bogus: false};
-        },
+      shouldComponentUpdate: function() {
+        return undefined;
+      },
 
-        shouldComponentUpdate: function() {
-          return undefined;
-        },
+      render: function() {
+        return <div />;
+      }
+    });
 
-        render: function() {
-          return <div />;
-        }
-      });
+    var instance = ReactTestUtils.renderIntoDocument(<Component />);
+    instance.setState({bogus: true});
 
-      var instance = ReactTestUtils.renderIntoDocument(<Component />);
-      instance.setState({bogus: true});
-
-      expect(console.warn.mock.calls.length).toBe(1);
-      expect(console.warn.mock.calls[0][0]).toBe(
-        'Component.shouldComponentUpdate(): Returned undefined instead of a ' +
-        'boolean value. Make sure to return true or false.'
-      );
-    } finally {
-      console.warn = warn;
-    }
+    expect(console.warn.argsForCall.length).toBe(1);
+    expect(console.warn.argsForCall[0][0]).toBe(
+      'Component.shouldComponentUpdate(): Returned undefined instead of a ' +
+      'boolean value. Make sure to return true or false.'
+    );
   });
 
   it('should pass context', function() {
@@ -579,8 +562,8 @@ describe('ReactCompositeComponent', function() {
 
     // Two warnings, one for the component and one for the div
     // We may want to make this expect one warning in the future
-    expect(console.warn.mock.calls.length).toBe(1);
-    expect(console.warn.mock.calls[0][0]).toBe(
+    expect(console.warn.argsForCall.length).toBe(1);
+    expect(console.warn.argsForCall[0][0]).toBe(
       'Warning: owner-based and parent-based contexts differ '+
       '(values: `bar` vs `undefined`) for key (foo) '+
       'while mounting Component (see: http://fb.me/react-context-by-parent)'
@@ -622,8 +605,8 @@ describe('ReactCompositeComponent', function() {
 
     // Two warnings, one for the component and one for the div
     // We may want to make this expect one warning in the future
-    expect(console.warn.mock.calls.length).toBe(1);
-    expect(console.warn.mock.calls[0][0]).toBe(
+    expect(console.warn.argsForCall.length).toBe(1);
+    expect(console.warn.argsForCall[0][0]).toBe(
       'Warning: owner-based and parent-based contexts differ ' +
       '(values: `noise` vs `bar`) for key (foo) while mounting Component ' +
       '(see: http://fb.me/react-context-by-parent)'
@@ -665,7 +648,7 @@ describe('ReactCompositeComponent', function() {
     });
     React.render(<Parent>{componentWithSameContext}</Parent>, div);
 
-    expect(console.warn.mock.calls.length).toBe(0);
+    expect(console.warn.argsForCall.length).toBe(0);
 
     var componentWithDifferentContext = React.withContext({foo: 'noise'}, function() {
       return <Component />;
@@ -674,8 +657,8 @@ describe('ReactCompositeComponent', function() {
 
     // Two warnings, one for the component and one for the div
     // We may want to make this expect one warning in the future
-    expect(console.warn.mock.calls.length).toBe(1);
-    expect(console.warn.mock.calls[0][0]).toBe(
+    expect(console.warn.argsForCall.length).toBe(1);
+    expect(console.warn.argsForCall[0][0]).toBe(
       'Warning: owner-based and parent-based contexts differ ' +
       '(values: `noise` vs `bar`) for key (foo) while mounting Component ' +
       '(see: http://fb.me/react-context-by-parent)'
@@ -728,8 +711,8 @@ describe('ReactCompositeComponent', function() {
 
     // Two warnings, one for the component and one for the div
     // We may want to make this expect one warning in the future
-    expect(console.warn.mock.calls.length).toBe(1);
-    expect(console.warn.mock.calls[0][0]).toBe(
+    expect(console.warn.argsForCall.length).toBe(1);
+    expect(console.warn.argsForCall[0][0]).toBe(
       'Warning: owner-based and parent-based contexts differ ' +
       '(values: `noise` vs `bar`) for key (foo) while mounting Component ' +
       '(see: http://fb.me/react-context-by-parent)'
@@ -810,7 +793,6 @@ describe('ReactCompositeComponent', function() {
   });
 
   it('should disallow nested render calls', function() {
-    spyOn(console, 'warn');
     var Inner = React.createClass({
       render: function() {
         return <div />;
diff --git a/src/utils/__tests__/cloneWithProps-test.js b/src/utils/__tests__/cloneWithProps-test.js
index e4712ea00b..f6bd903325 100644
--- a/src/utils/__tests__/cloneWithProps-test.js
+++ b/src/utils/__tests__/cloneWithProps-test.js
@@ -82,6 +82,8 @@ describe('cloneWithProps', function() {
   });
 
   it('should warn when cloning with refs', function() {
+    spyOn(console, 'warn');
+
     var Grandparent = React.createClass({
       render: function() {
         return <Parent><div ref="yolo" /></Parent>;
@@ -97,17 +99,9 @@ describe('cloneWithProps', function() {
       }
     });
 
-    var _warn = console.warn;
-
-    try {
-      console.warn = mocks.getMockFunction();
-
-      var component = ReactTestUtils.renderIntoDocument(<Grandparent />);
-      expect(component.refs).toBe(emptyObject);
-      expect(console.warn.mock.calls.length).toBe(1);
-    } finally {
-      console.warn = _warn;
-    }
+    var component = ReactTestUtils.renderIntoDocument(<Grandparent />);
+    expect(component.refs).toBe(emptyObject);
+    expect(console.warn.argsForCall.length).toBe(1);
   });
 
   it('should transfer the key property', function() {