fix: check for element in text

Author: eddyerburgh

src/wrappers/wrapper.js

@@ -312,6 +312,10 @@ export default class Wrapper implements BaseWrapper {
    * Return text of wrapper element
    */
   text (): string {
+    if (!this.element) {
+      throwError('cannot call wrapper.text() on a wrapper without an element')
+    }
+
     return this.element.textContent
   }
 

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

@@ -9,4 +9,13 @@ describe('text', () => {
 
     expect(wrapper.text()).to.equal(text)
   })
+
+  it('throws error if wrapper does not contain eleemnt', () => {
+    const compiled = compileToFunctions(`<div />`)
+    const wrapper = mount(compiled)
+    wrapper.element = null
+    const fn = () => wrapper.text()
+    const message = '[vue-test-utils]: cannot call wrapper.text() on a wrapper without an element'
+    expect(fn).to.throw().with.property('message', message)
+  })
 })