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diff --git a/spec/javascripts/smart_interval_spec.js.es6 b/spec/javascripts/smart_interval_spec.js.es6
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index 00000000000..651d1f0f975
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+++ b/spec/javascripts/smart_interval_spec.js.es6
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+//= require jquery
+//= require smart_interval
+
+(() => {
+  const DEFAULT_MAX_INTERVAL = 100;
+  const DEFAULT_STARTING_INTERVAL = 5;
+  const DEFAULT_SHORT_TIMEOUT = 75;
+  const DEFAULT_LONG_TIMEOUT = 1000;
+  const DEFAULT_INCREMENT_FACTOR = 2;
+
+  function createDefaultSmartInterval(config) {
+    const defaultParams = {
+      callback: () => {},
+      startingInterval: DEFAULT_STARTING_INTERVAL,
+      maxInterval: DEFAULT_MAX_INTERVAL,
+      incrementByFactorOf: DEFAULT_INCREMENT_FACTOR,
+      delayStartBy: 0,
+      lazyStart: false,
+    };
+
+    if (config) {
+      _.extend(defaultParams, config);
+    }
+
+    return new gl.SmartInterval(defaultParams);
+  }
+
+  describe('SmartInterval', function () {
+    describe('Increment Interval', function () {
+      beforeEach(function () {
+        this.smartInterval = createDefaultSmartInterval();
+      });
+
+      it('should increment the interval delay', function (done) {
+        const interval = this.smartInterval;
+        setTimeout(() => {
+          const intervalConfig = this.smartInterval.cfg;
+          const iterationCount = 4;
+          const maxIntervalAfterIterations = intervalConfig.startingInterval *
+            Math.pow(intervalConfig.incrementByFactorOf, (iterationCount - 1)); // 40
+          const currentInterval = interval.getCurrentInterval();
+
+          // Provide some flexibility for performance of testing environment
+          expect(currentInterval).toBeGreaterThan(intervalConfig.startingInterval);
+          expect(currentInterval <= maxIntervalAfterIterations).toBeTruthy();
+
+          done();
+        }, DEFAULT_SHORT_TIMEOUT); // 4 iterations, increment by 2x = (5 + 10 + 20 + 40)
+      });
+
+      it('should not increment past maxInterval', function (done) {
+        const interval = this.smartInterval;
+
+        setTimeout(() => {
+          const currentInterval = interval.getCurrentInterval();
+          expect(currentInterval).toBe(interval.cfg.maxInterval);
+
+          done();
+        }, DEFAULT_LONG_TIMEOUT);
+      });
+    });
+
+    describe('Public methods', function () {
+      beforeEach(function () {
+        this.smartInterval = createDefaultSmartInterval();
+      });
+
+      it('should cancel an interval', function (done) {
+        const interval = this.smartInterval;
+
+        setTimeout(() => {
+          interval.cancel();
+
+          const intervalId = interval.state.intervalId;
+          const currentInterval = interval.getCurrentInterval();
+          const intervalLowerLimit = interval.cfg.startingInterval;
+
+          expect(intervalId).toBeUndefined();
+          expect(currentInterval).toBe(intervalLowerLimit);
+
+          done();
+        }, DEFAULT_SHORT_TIMEOUT);
+      });
+
+      it('should resume an interval', function (done) {
+        const interval = this.smartInterval;
+
+        setTimeout(() => {
+          interval.cancel();
+
+          interval.resume();
+
+          const intervalId = interval.state.intervalId;
+
+          expect(intervalId).toBeTruthy();
+
+          done();
+        }, DEFAULT_SHORT_TIMEOUT);
+      });
+    });
+
+    describe('DOM Events', function () {
+      beforeEach(function () {
+        // This ensures DOM and DOM events are initialized for these specs.
+        fixture.set('<div></div>');
+
+        this.smartInterval = createDefaultSmartInterval();
+      });
+
+      it('should pause when page is not visible', function (done) {
+        const interval = this.smartInterval;
+
+        setTimeout(() => {
+          expect(interval.state.intervalId).toBeTruthy();
+
+          // simulates triggering of visibilitychange event
+          interval.state.pageVisibility = 'hidden';
+          interval.handleVisibilityChange();
+
+          expect(interval.state.intervalId).toBeUndefined();
+          done();
+        }, DEFAULT_SHORT_TIMEOUT);
+      });
+
+      it('should resume when page is becomes visible at the previous interval', function (done) {
+        const interval = this.smartInterval;
+
+        setTimeout(() => {
+          expect(interval.state.intervalId).toBeTruthy();
+
+          // simulates triggering of visibilitychange event
+          interval.state.pageVisibility = 'hidden';
+          interval.handleVisibilityChange();
+
+          expect(interval.state.intervalId).toBeUndefined();
+
+          // simulates triggering of visibilitychange event
+          interval.state.pageVisibility = 'visible';
+          interval.handleVisibilityChange();
+
+          expect(interval.state.intervalId).toBeTruthy();
+
+          done();
+        }, DEFAULT_SHORT_TIMEOUT);
+      });
+
+      it('should cancel on page unload', function (done) {
+        const interval = this.smartInterval;
+
+        setTimeout(() => {
+          $(document).trigger('page:before-unload');
+          expect(interval.state.intervalId).toBeUndefined();
+          expect(interval.getCurrentInterval()).toBe(interval.cfg.startingInterval);
+          done();
+        }, DEFAULT_SHORT_TIMEOUT);
+      });
+    });
+  });
+})(window.gl || (window.gl = {}));