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docs: adds a cost input example to showcase fireEvent with React (#196)
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| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,65 @@ | ||
| import React from 'react' | ||
| import {render, fireEvent, cleanup} from 'react-testing-library' | ||
|
|
||
| class CostInput extends React.Component { | ||
| state = { | ||
| value: '', | ||
| } | ||
|
|
||
| removeDollarSign = value => (value[0] === '$' ? value.slice(1) : value) | ||
| getReturnValue = value => (value === '' ? '' : `$${value}`) | ||
| handleChange = ev => { | ||
| ev.preventDefault() | ||
| const inputtedValue = ev.currentTarget.value | ||
| const noDollarSign = this.removeDollarSign(inputtedValue) | ||
| if (isNaN(noDollarSign)) return | ||
| this.setState({value: this.getReturnValue(noDollarSign)}) | ||
| } | ||
|
|
||
| render() { | ||
| return ( | ||
| <input | ||
| value={this.state.value} | ||
| aria-label="cost-input" | ||
| onChange={this.handleChange} | ||
| /> | ||
| ) | ||
| } | ||
| } | ||
|
|
||
| const setup = () => { | ||
| const utils = render(<CostInput />) | ||
| const input = utils.getByLabelText('cost-input') | ||
| return { | ||
| input, | ||
| ...utils, | ||
| } | ||
| } | ||
|
|
||
| afterEach(cleanup) | ||
|
|
||
| test('It should keep a $ in front of the input', () => { | ||
| const {input} = setup() | ||
| fireEvent.change(input, {target: {value: '23'}}) | ||
| expect(input.value).toBe('$23') | ||
| }) | ||
| test('It should allow a $ to be in the input when the value is changed', () => { | ||
| const {input} = setup() | ||
| fireEvent.change(input, {target: {value: '$23.0'}}) | ||
| expect(input.value).toBe('$23.0') | ||
| }) | ||
|
|
||
| test('It should not allow letters to be inputted', () => { | ||
| const {input} = setup() | ||
| expect(input.value).toBe('') // empty before | ||
| fireEvent.change(input, {target: {value: 'Good Day'}}) | ||
| expect(input.value).toBe('') //empty after | ||
| }) | ||
|
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||
| test('It should allow the $ to be deleted', () => { | ||
| const {input} = setup() | ||
| fireEvent.change(input, {target: {value: '23'}}) | ||
| expect(input.value).toBe('$23') // need to make a change so React registers "" as a change | ||
| fireEvent.change(input, {target: {value: ''}}) | ||
| expect(input.value).toBe('') | ||
| }) |