prevent "Zero-day streak" giving a 21-day streak achievement + tests - fixes #2578 (#9688)

* prevent "Zero-day streak" giving a 21-day streak achievement - fixes #2578

* add tests for streak achievements

* remove .only from set of tests

* refactor(test): fix linting

test/common/ops/scoreTask.test.js

@@ -74,13 +74,6 @@ describe('shared.ops.scoreTask', () => {
     }
   });
 
-  it('checks that the streak parameters affects the score', () => {
-    let task = generateDaily({ userId: ref.afterUser._id, text: 'task to check streak' });
-    scoreTask({ user: ref.afterUser, task, direction: 'up', cron: false });
-    scoreTask({ user: ref.afterUser, task, direction: 'up', cron: false });
-    expect(task.streak).to.eql(2);
-  });
-
   it('completes when the task direction is up', () => {
     let task = generateTodo({ userId: ref.afterUser._id, text: 'todo to complete', cron: false });
     scoreTask({ user: ref.afterUser, task, direction: 'up' });
@@ -123,6 +116,64 @@ describe('shared.ops.scoreTask', () => {
     });
   });
 
+  it('checks that the streak parameters affects the score', () => {
+    let task = generateDaily({ userId: ref.afterUser._id, text: 'task to check streak' });
+    scoreTask({ user: ref.afterUser, task, direction: 'up', cron: false });
+    scoreTask({ user: ref.afterUser, task, direction: 'up', cron: false });
+    expect(task.streak).to.eql(2);
+  });
+
+  describe('verifies that 21-day streak achievements are given/removed correctly', () => {
+    let initialStreakCount = 20; // 1 before the streak achievement is awarded
+    beforeEach(() => {
+      ref = beforeAfter();
+    });
+
+    it('awards the first streak achievement', () => {
+      let task = generateDaily({ userId: ref.afterUser._id, text: 'some daily', streak: initialStreakCount });
+      scoreTask({ user: ref.afterUser, task, direction: 'up' });
+      expect(ref.afterUser.achievements.streak).to.equal(1);
+    });
+
+    it('increments the streak achievement for a second streak', () => {
+      let task1 = generateDaily({ userId: ref.afterUser._id, text: 'first daily', streak: initialStreakCount });
+      scoreTask({ user: ref.afterUser, task: task1, direction: 'up' });
+      let task2 = generateDaily({ userId: ref.afterUser._id, text: 'second daily', streak: initialStreakCount });
+      scoreTask({ user: ref.afterUser, task: task2, direction: 'up' });
+      expect(ref.afterUser.achievements.streak).to.equal(2);
+    });
+
+    it('removes the first streak achievement when unticking a Daily', () => {
+      let task = generateDaily({ userId: ref.afterUser._id, text: 'some daily', streak: initialStreakCount });
+      scoreTask({ user: ref.afterUser, task, direction: 'up' });
+      scoreTask({ user: ref.afterUser, task, direction: 'down' });
+      expect(ref.afterUser.achievements.streak).to.equal(0);
+    });
+
+    it('decrements a multiple streak achievement when unticking a Daily', () => {
+      let task1 = generateDaily({ userId: ref.afterUser._id, text: 'first daily', streak: initialStreakCount });
+      scoreTask({ user: ref.afterUser, task: task1, direction: 'up' });
+      let task2 = generateDaily({ userId: ref.afterUser._id, text: 'second daily', streak: initialStreakCount });
+      scoreTask({ user: ref.afterUser, task: task2, direction: 'up' });
+      scoreTask({ user: ref.afterUser, task: task2, direction: 'down' });
+      expect(ref.afterUser.achievements.streak).to.equal(1);
+    });
+
+    it('does not give a streak achievement for a streak of zero', () => {
+      let task = generateDaily({ userId: ref.afterUser._id, text: 'some daily', streak: -1 });
+      scoreTask({ user: ref.afterUser, task, direction: 'up' });
+      expect(ref.afterUser.achievements.streak).to.be.undefined;
+    });
+
+    it('does not remove a streak achievement when unticking a Daily gives a streak of zero', () => {
+      let task1 = generateDaily({ userId: ref.afterUser._id, text: 'first daily', streak: initialStreakCount });
+      scoreTask({ user: ref.afterUser, task: task1, direction: 'up' });
+      let task2 = generateDaily({ userId: ref.afterUser._id, text: 'second daily', streak: 1 });
+      scoreTask({ user: ref.afterUser, task: task2, direction: 'down' });
+      expect(ref.afterUser.achievements.streak).to.equal(1);
+    });
+  });
+
   describe('scores', () => {
     let options = {};
     let habit;

website/common/script/ops/scoreTask.js

@@ -238,14 +238,14 @@ module.exports = function scoreTask (options = {}, req = {}) {
       if (direction === 'up') {
         task.streak += 1;
         // Give a streak achievement when the streak is a multiple of 21
-        if (task.streak % 21 === 0) {
+        if (task.streak !== 0 && task.streak % 21 === 0) {
           user.achievements.streak = user.achievements.streak ? user.achievements.streak + 1 : 1;
           if (user.addNotification) user.addNotification('STREAK_ACHIEVEMENT');
         }
         task.completed = true;
       } else if (direction === 'down') {
         // Remove a streak achievement if streak was a multiple of 21 and the daily was undone
-        if (task.streak % 21 === 0) user.achievements.streak = user.achievements.streak ? user.achievements.streak - 1 : 0;
+        if (task.streak !== 0 && task.streak % 21 === 0) user.achievements.streak = user.achievements.streak ? user.achievements.streak - 1 : 0;
         task.streak -= 1;
         task.completed = false;
       }