```
render () {
  <input type="number" value={this.props.value} />
}
```

for example, when the original value is '.98', we need format it to '0.98'. but it is not  take effect。

```javascript
class Test extends React.Component {
 state = {
    value: '.98',
  }
 changeValue = () => {
    alert(0.98);
    this.setState({
      value: '0.98',
    });
  }

 render() {
    return <div>
      <input type="number" value={this.state.value} />
      <button onClick={this.changeValue}>changeValue</button>
    </div>;
  }
}

ReactDOM.render(<Test />, mountNode);
```



ReactTestUtils.Simulate.change(bNode);
    
    expect(aNode.checked).toBe(true);
    expect(bNode.checked).toBe(false);
  });
  it('should warn with value and no onChange handler and readOnly specified', () => {
    ReactTestUtils.renderIntoDocument(
      <input type="text" value="zoink" readOnly={true} />,
    );
    expectDev(console.error.calls.count()).toBe(0);
    ReactTestUtils.renderIntoDocument(
      <input type="text" value="zoink" readOnly={false} />,
    );
    expectDev(console.error.calls.count()).toBe(1);
    expectDev(normalizeCodeLocInfo(console.error.calls.argsFor(0)[0])).toBe(
      'Warning: Failed form propType: You provided a `value` prop to a form ' +
        'field without an `onChange` handler. This will render a read-only ' +
        'field. If the field should be mutable use `defaultValue`. ' +
        'Otherwise, set either `onChange` or `readOnly`.\n' +
        '    in input (at **)',
    );
  });
  it('should have a this value of undefined if bind is not used', () => {
    var unboundInputOnChange = function() {
      expect(this).toBe(undefined);
    };
    var instance = <input type="text" onChange={unboundInputOnChange} />;
    instance = ReactTestUtils.renderIntoDocument(instance);
    ReactTestUtils.Simulate.change(instance);