我写了以下测试：

  it('componentDidUpdate should mount and change props',() => {
    const onChange = jest.fn();
    const wrapper = enzyme
      .mount(
        <JsonInput
          onChange={onChange}
          onValueChange={mockOnValueChange}
          value={exampleJsonStringValidated}
        />,{ wrappingComponent: withTestThemeWrapper },);
    console.log(wrapper.debug());
    expect(wrapper.find(JsonInput).hasClass('valid')).toEqual(true);
    wrapper.setProps({ value: exampleJsonStringNotValidated });
    expect(wrapper.find(JsonInput).hasClass('invalid')).toBe(true);
  });

和console.log显示：

  <JsonInput onChange={[Function: mockConstructor]} onValueChange={[Function: mockConstructor]} value="{"firstName":"John","lastName":"Doe","age":210}">
    <styled.textarea onChange={[Function]} value="{"firstName":"John","age":210}" height="">
      <StyledComponent onChange={[Function]} value="{"firstName":"John","age":210}" height="" forwardedComponent={{...}} forwardedRef={{...}}>
        <textarea onChange={[Function]} value="{"firstName":"John","age":210}" height="" classname="sc-bdVaJa lavZWj" />
      </StyledComponent>
    </styled.textarea>
  </JsonInput>

在组件中，代码classname="sc-bdVaJa lavZWj"是valid和invalid，但现在我看到没有可读的类名，如何对其进行测试？

组件（样式部分）

export const styledtextArea = styled.textarea<{ height: string }>`
margin: 0;
box-sizing: border-box;
width: 350px;
outline: none;
border: none;
height: ${props => props.height};
box-shadow: 0 1px 3px 0 rgba(0,0.23);
background-color: ${props => props.theme.palette.foreground};
color: ${props => props.theme.palette.text};
cursor: text;

&:focus{
  border-bottom: 2px solid ${props => props.theme.palette.active};
}

&:valid{
  border-bottom: 2px solid ${props => props.theme.palette.positive};
}

&:invalid{
  border-bottom: 2px solid ${props => props.theme.palette.negative};
}
`;

并渲染：

render() {
  // to exclude unknown property 'onValueChange' for JsonInput for DevTools
  const { height = '',onValueChange,...restProps } = this.props;
  return (
    <styledtextArea
      ref={this.JsonInputRef}
      {...restProps}
      onChange={this.handleValueChange}
      height={height}
    />
  );
}