1 files changed, 128 insertions, 0 deletions
diff --git a/spec/frontend/__helpers__/vuex_action_helper.js b/spec/frontend/__helpers__/vuex_action_helper.js
new file mode 100644
index 00000000000..e482a8fbc71
--- /dev/null
+++ b/spec/frontend/__helpers__/vuex_action_helper.js
@@ -0,0 +1,128 @@
+const noop = () => {};
+
+/**
+ * Helper for testing action with expected mutations inspired in
+ * https://vuex.vuejs.org/en/testing.html
+ *
+ * @param {(Function|Object)} action to be tested, or object of named parameters
+ * @param {Object} payload will be provided to the action
+ * @param {Object} state will be provided to the action
+ * @param {Array} [expectedMutations=[]] mutations expected to be committed
+ * @param {Array} [expectedActions=[]] actions expected to be dispatched
+ * @param {Function} [done=noop] to be executed after the tests
+ * @return {Promise}
+ *
+ * @example
+ * testAction(
+ *   actions.actionName, // action
+ *   { }, // mocked payload
+ *   state, //state
+ *   // expected mutations
+ *   [
+ *    { type: types.MUTATION}
+ *    { type: types.MUTATION_1, payload: expect.any(Number)}
+ *   ],
+ *   // expected actions
+ *   [
+ *    { type: 'actionName', payload: {param: 'foobar'}},
+ *    { type: 'actionName1'}
+ *   ]
+ *   done,
+ * );
+ *
+ * @example
+ * testAction(
+ *   actions.actionName, // action
+ *   { }, // mocked payload
+ *   state, //state
+ *   [ { type: types.MUTATION} ], // expected mutations
+ *   [], // expected actions
+ * ).then(done)
+ * .catch(done.fail);
+ *
+ * @example
+ * await testAction({
+ *   action: actions.actionName,
+ *   payload: { deleteListId: 1 },
+ *   state: { lists: [1, 2, 3] },
+ *   expectedMutations: [ { type: types.MUTATION} ],
+ *   expectedActions: [],
+ * })
+ */
+export default (
+  actionArg,
+  payloadArg,
+  stateArg,
+  expectedMutationsArg = [],
+  expectedActionsArg = [],
+  doneArg = noop,
+) => {
+  let action = actionArg;
+  let payload = payloadArg;
+  let state = stateArg;
+  let expectedMutations = expectedMutationsArg;
+  let expectedActions = expectedActionsArg;
+  let done = doneArg;
+
+  if (typeof actionArg !== 'function') {
+    ({
+      action,
+      payload,
+      state,
+      expectedMutations = [],
+      expectedActions = [],
+      done = noop,
+    } = actionArg);
+  }
+
+  const mutations = [];
+  const actions = [];
+
+  // mock commit
+  const commit = (type, mutationPayload) => {
+    const mutation = { type };
+
+    if (typeof mutationPayload !== 'undefined') {
+      mutation.payload = mutationPayload;
+    }
+
+    mutations.push(mutation);
+  };
+
+  // mock dispatch
+  const dispatch = (type, actionPayload) => {
+    const dispatchedAction = { type };
+
+    if (typeof actionPayload !== 'undefined') {
+      dispatchedAction.payload = actionPayload;
+    }
+
+    actions.push(dispatchedAction);
+  };
+
+  const validateResults = () => {
+    expect({
+      mutations,
+      actions,
+    }).toEqual({
+      mutations: expectedMutations,
+      actions: expectedActions,
+    });
+    done();
+  };
+
+  const result = action(
+    { commit, state, dispatch, rootState: state, rootGetters: state, getters: state },
+    payload,
+  );
+
+  return (result || new Promise((resolve) => setImmediate(resolve)))
+    .catch((error) => {
+      validateResults();
+      throw error;
+    })
+    .then((data) => {
+      validateResults();
+      return data;
+    });
+};