feat(wrapper): add support for getting prop, attribute and classes by…

… key (#941)

docs/api/wrapper/attributes.md

@@ -1,8 +1,11 @@
-## attributes()
+## attributes([key])
 
-Returns `Wrapper` DOM node attribute object.
+Returns `Wrapper` DOM node attribute object. If `key` is provided, the value for the `key` will be returned.
 
-- **Returns:** `{[attribute: string]: any}`
+- **Arguments:**
+  - `{string} key`  **optional**
+
+- **Returns:** `{[attribute: string]: any} | string`
 
 - **Example:**
 
@@ -12,4 +15,5 @@ import Foo from './Foo.vue'
 
 const wrapper = mount(Foo)
 expect(wrapper.attributes().id).toBe('foo')
+expect(wrapper.attributes('id')).toBe('foo')
 ```

docs/api/wrapper/classes.md

@@ -1,10 +1,13 @@
-## classes()
+## classes([className])
 
 Return `Wrapper` DOM node classes.
 
-Returns Array of class names.
+Returns Array of class names. Or a boolean if a class name is provided.
 
-- **Returns:** `Array<{string}>`
+- **Arguments:**
+  - `{string} className`  **optional**
+
+- **Returns:** `Array<{string}> | boolean`
 
 - **Example:**
 
@@ -14,4 +17,5 @@ import Foo from './Foo.vue'
 
 const wrapper = mount(Foo)
 expect(wrapper.classes()).toContain('bar')
+expect(wrapper.classes('bar')).toBe(true)
 ```

docs/api/wrapper/props.md

@@ -1,10 +1,13 @@
-## props()
+## props([key])
 
-Return `Wrapper` `vm` props object.
+Return `Wrapper` `vm` props object. If `key` is provided, the value for the `key` will be returned.
 
 **Note the Wrapper must contain a Vue instance.**
 
-- **Returns:** `{[prop: string]: any}`
+- **Arguments:**
+  - `{string} key`  **optional**
+
+- **Returns:** `{[prop: string]: any} | any`
 
 - **Example:**
 
@@ -18,4 +21,5 @@ const wrapper = mount(Foo, {
   }
 })
 expect(wrapper.props().bar).toBe('baz')
+expect(wrapper.props('bar')).toBe('baz')
 ```

flow/wrapper.flow.js

@@ -9,8 +9,8 @@ declare type Components = { [name: string]: Component };
 declare interface BaseWrapper {
   // eslint-disable-line no-undef
   at(index: number): Wrapper | void;
-  attributes(): { [name: string]: string } | void;
-  classes(): Array<string> | void;
+  attributes(key?: string): { [name: string]: string } | string | void;
+  classes(className?: string): Array<string> | boolean | void;
   contains(selector: Selector): boolean | void;
   emitted(
     event?: string
@@ -31,7 +31,7 @@ declare interface BaseWrapper {
   isVisible(): boolean | void;
   isVueInstance(): boolean | void;
   name(): string | void;
-  props(): { [name: string]: any } | void;
+  props(key?: string): { [name: string]: any } | any | void;
   text(): string | void;
   setData(data: Object): void;
   setComputed(computed: Object): void;

packages/test-utils/src/wrapper.js

@@ -78,22 +78,25 @@ export default class Wrapper implements BaseWrapper {
   /**
    * Returns an Object containing all the attribute/value pairs on the element.
    */
-  attributes (): { [name: string]: string } {
+  attributes (key?: string): { [name: string]: string } | string {
     const attributes = this.element.attributes
     const attributeMap = {}
     for (let i = 0; i < attributes.length; i++) {
       const att = attributes.item(i)
       attributeMap[att.localName] = att.value
     }
+    if (key) {
+      return attributeMap[key]
+    }
     return attributeMap
   }
 
   /**
    * Returns an Array containing all the classes on the element
    */
-  classes (): Array<string> {
-    const className = this.element.getAttribute('class')
-    let classes = className ? className.split(' ') : []
+  classes (className?: string): Array<string> | boolean {
+    const classAttribute = this.element.getAttribute('class')
+    let classes = classAttribute ? classAttribute.split(' ') : []
     // Handle converting cssmodules identifiers back to the original class name
     if (this.vm && this.vm.$style) {
       const cssModuleIdentifiers = Object.keys(this.vm.$style)
@@ -106,9 +109,17 @@ export default class Wrapper implements BaseWrapper {
           return acc
         }, {})
       classes = classes.map(
-        className => cssModuleIdentifiers[className] || className
+        name => cssModuleIdentifiers[name] || name
       )
     }
+
+    if (className) {
+      if (classes.indexOf(className) > -1) {
+        return true
+      } else {
+        return false
+      }
+    }
     return classes
   }
 
@@ -436,7 +447,7 @@ export default class Wrapper implements BaseWrapper {
   /**
    * Returns an Object containing the prop name/value pairs on the element
    */
-  props (): { [name: string]: any } {
+  props (key?: string): { [name: string]: any } | any {
     if (this.isFunctionalComponent) {
       throwError(
         `wrapper.props() cannot be called on a mounted ` +
@@ -457,6 +468,11 @@ export default class Wrapper implements BaseWrapper {
         }
       })
     }
+
+    if (key) {
+      return props[key]
+    }
+
     return props
   }
 
@@ -468,6 +484,7 @@ export default class Wrapper implements BaseWrapper {
       throwError('wrapper.setChecked() must be passed a boolean')
     }
     const tagName = this.element.tagName
+    // $FlowIgnore
     const type = this.attributes().type
 
     if (tagName === 'SELECT') {
@@ -515,6 +532,7 @@ export default class Wrapper implements BaseWrapper {
    */
   setSelected (): void {
     const tagName = this.element.tagName
+    // $FlowIgnore
     const type = this.attributes().type
 
     if (tagName === 'OPTION') {
@@ -744,6 +762,7 @@ export default class Wrapper implements BaseWrapper {
    */
   setValue (value: any): void {
     const tagName = this.element.tagName
+    // $FlowIgnore
     const type = this.attributes().type
 
     if (tagName === 'SELECT') {

packages/test-utils/types/index.d.ts

@@ -56,8 +56,11 @@ interface BaseWrapper {
   visible (): boolean
 
   attributes(): { [name: string]: string }
+  attributes(key: string): string | void
   classes(): Array<string>
+  classes(className: string): boolean
   props(): { [name: string]: any }
+  props(key: string): any | void
 
   hasAttribute (attribute: string, value: string): boolean
   hasClass (className: string): boolean

test/specs/wrapper/attributes.spec.js

@@ -15,4 +15,20 @@ describeWithShallowAndMount('attributes', mountingMethod => {
     const wrapper = mountingMethod(compiled)
     expect(wrapper.attributes()).to.eql({})
   })
+
+  it('returns the given attribute if wrapper contains attribute matching value', () => {
+    const attribute = 'attribute'
+    const value = 'value'
+    const compiled = compileToFunctions(`<div ${attribute}=${value}></div>`)
+    const wrapper = mountingMethod(compiled)
+    expect(wrapper.attributes('attribute')).to.eql(value)
+  })
+
+  it('returns undefined if the wrapper does not contain the matching value', () => {
+    const attribute = 'attribute'
+    const value = 'value'
+    const compiled = compileToFunctions(`<div ${attribute}=${value}></div>`)
+    const wrapper = mountingMethod(compiled)
+    expect(wrapper.attributes('fake')).to.eql(undefined)
+  })
 })

test/specs/wrapper/classes.spec.js

@@ -30,4 +30,20 @@ describeWithShallowAndMount('classes', mountingMethod => {
     expect(wrapper.classes()).to.contain('b-class')
     expect(wrapper.find('text').classes()).to.contain('c-class')
   })
+
+  it('returns true if the element has the class', () => {
+    const compiled = compileToFunctions(
+      '<svg class="a-class b-class"><text class="c-class"/></svg>'
+    )
+    const wrapper = mountingMethod(compiled)
+    expect(wrapper.classes('a-class')).to.eql(true)
+    expect(wrapper.classes('b-class')).to.eql(true)
+    expect(wrapper.find('text').classes('c-class')).to.eql(true)
+    expect(wrapper.classes('x-class')).to.eql(false)
+  })
+
+  it('returns false if the element does not have the class', () => {
+    const wrapper = mountingMethod(ComponentWithCssModules)
+    expect(wrapper.classes('x-class')).to.eql(false)
+  })
 })

test/specs/wrapper/props.spec.js

@@ -91,4 +91,23 @@ describeWithShallowAndMount('props', mountingMethod => {
       .to.throw()
       .with.property('message', message)
   })
+
+  it('returns the given prop if a key is provided', () => {
+    const prop1 = {}
+    const prop2 = 'string val'
+    const wrapper = mountingMethod(ComponentWithProps, {
+      propsData: { prop1, prop2 }
+    })
+    expect(wrapper.props('prop1')).to.eql({})
+    expect(wrapper.props('prop2')).to.eql('string val')
+  })
+
+  it('returns undefined if the given key is not found', () => {
+    const prop1 = {}
+    const prop2 = 'string val'
+    const wrapper = mountingMethod(ComponentWithProps, {
+      propsData: { prop1, prop2 }
+    })
+    expect(wrapper.props('propNotHere')).to.eql(undefined)
+  })
 })