✅ Add tests

test/unit/specs/helpers/options.spec.js

@@ -0,0 +1,30 @@
+import { mergeOptions } from 'src/helpers/options'
+
+describe('mergeOptions.js', () => {
+  const a = {
+    a: 'a',
+    b: 'a'
+  }
+
+  const b = {
+    a: 'b',
+    b: 'b'
+  }
+
+  const c = {
+    c: 'c'
+  }
+
+  it('should replace old a and b if a and b are new', () => {
+    let ab = mergeOptions(a, b)
+    expect(ab).to.have.property('a').and.to.equal('b')
+    expect(ab).to.have.property('b').and.to.equal('b')
+  })
+
+  it('should add c if c is new', () => {
+    let ac = mergeOptions(a, c)
+    expect(ac).to.have.property('a').and.to.equal('a')
+    expect(ac).to.have.property('b').and.to.equal('a')
+    expect(ac).to.have.property('c').and.to.equal('c')
+  })
+})