options computed test

test/unit/features/options/computed.spec.js

@@ -0,0 +1,110 @@
+import Vue from 'vue'
+
+describe('Options computed', () => {
+  it('basic usage', done => {
+    const vm = new Vue({
+      template: '<div>{{ b }}</div>',
+      data: {
+        a: 1
+      },
+      computed: {
+        b () {
+          return this.a + 1
+        }
+      }
+    }).$mount()
+    expect(vm.b).toBe(2)
+    expect(vm.$el.textContent).toBe('2')
+    vm.a = 2
+    expect(vm.b).toBe(3)
+    waitForUpdate(() => {
+      expect(vm.$el.textContent).toBe('3')
+    }).then(done)
+  })
+
+  it('with setter', done => {
+    const vm = new Vue({
+      template: '<div>{{ b }}</div>',
+      data: {
+        a: 1
+      },
+      computed: {
+        b: {
+          get () { return this.a + 1 },
+          set (v) { this.a = v - 1 }
+        }
+      }
+    }).$mount()
+    expect(vm.b).toBe(2)
+    expect(vm.$el.textContent).toBe('2')
+    vm.a = 2
+    expect(vm.b).toBe(3)
+    waitForUpdate(() => {
+      expect(vm.$el.textContent).toBe('3')
+      vm.b = 1
+      expect(vm.a).toBe(0)
+    }).then(() => {
+      expect(vm.$el.textContent).toBe('1')
+    }).then(done)
+  })
+
+  it('watching computed', done => {
+    const spy = jasmine.createSpy('watch computed')
+    const vm = new Vue({
+      data: {
+        a: 1
+      },
+      computed: {
+        b () { return this.a + 1 }
+      }
+    })
+    vm.$watch('b', spy)
+    vm.a = 2
+    waitForUpdate(() => {
+      expect(spy).toHaveBeenCalledWith(3, 2)
+    }).then(done)
+  })
+
+  it('caching', () => {
+    const spy = jasmine.createSpy('cached computed')
+    const vm = new Vue({
+      data: {
+        a: 1
+      },
+      computed: {
+        b () {
+          spy()
+          return this.a + 1
+        }
+      }
+    })
+    expect(spy.calls.count()).toBe(0)
+    vm.b
+    expect(spy.calls.count()).toBe(1)
+    vm.b
+    expect(spy.calls.count()).toBe(1)
+  })
+
+  it('cache: false', () => {
+    const spy = jasmine.createSpy('cached computed')
+    const vm = new Vue({
+      data: {
+        a: 1
+      },
+      computed: {
+        b: {
+          cache: false,
+          get () {
+            spy()
+            return this.a + 1
+          }
+        }
+      }
+    })
+    expect(spy.calls.count()).toBe(0)
+    vm.b
+    expect(spy.calls.count()).toBe(1)
+    vm.b
+    expect(spy.calls.count()).toBe(2)
+  })
+})