feat: add attributes, classes, and props to wrapper type definitions (#311)

* Add wrapper attributes/classes to TypeScript types

* Add wrapper attributes/classes to Flow types

* Add wrapper props to TypeScript types

* Add wrapper props to Flow types

* Flow types can return void

* TypeScript types can return void

Author: pshrmn

Diff for: flow/wrapper.flow.js

@@ -7,6 +7,8 @@ declare type Selector = any
 
 declare interface BaseWrapper { // eslint-disable-line no-undef
     at(index: number): Wrapper | void,
+    attributes(): { [name: string]: string } | void,
+    classes(): Array<string> | void,
     contains(selector: Selector): boolean | void,
     emitted(event?: string): { [name: string]: Array<Array<any>> } | Array<Array<any>> | void,
     emittedByOrder(): Array<{ name: string; args: Array<any> }> | void,
@@ -22,6 +24,7 @@ declare interface BaseWrapper { // eslint-disable-line no-undef
     isEmpty(): boolean | void,
     isVueInstance(): boolean | void,
     name(): string | void,
+    props(): { [name: string]: any } | void,
     text(): string | void,
     setData(data: Object): void,
     setComputed(computed: Object): void,

Diff for: types/index.d.ts

@@ -40,6 +40,10 @@ interface BaseWrapper {
   contains (selector: Selector): boolean
   exists (): boolean
 
+  attributes(): { [name: string]: string } | void
+  classes(): Array<string> | void
+  props(): { [name: string]: any } | void
+
   hasAttribute (attribute: string, value: string): boolean
   hasClass (className: string): boolean
   hasProp (prop: string, value: any): boolean