fix: return boolean in hasAttribute

Author: eddyerburgh

src/wrappers/wrapper.js

@@ -66,7 +66,7 @@ export default class Wrapper implements BaseWrapper {
       throwError('wrapper.hasAttribute() must be passed value as a string')
     }
 
-    return this.element && this.element.getAttribute(attribute) === value
+    return !!(this.element && this.element.getAttribute(attribute) === value)
   }
 
   /**

test/unit/specs/mount/Wrapper/hasAttribute.spec.js

@@ -16,6 +16,13 @@ describe('hasAttribute', () => {
     expect(wrapper.hasAttribute('attribute', 'value')).to.equal(false)
   })
 
+  it('returns false if wrapper element is null', () => {
+    const compiled = compileToFunctions('<div />')
+    const wrapper = mount(compiled)
+    wrapper.element = null
+    expect(wrapper.hasAttribute('attribute', 'value')).to.equal(false)
+  })
+
   it('throws an error if attribute is not a string', () => {
     const compiled = compileToFunctions('<div />')
     const wrapper = mount(compiled)