1 files changed, 243 insertions, 1 deletions
diff --git a/spec/frontend/monitoring/components/charts/options_spec.js b/spec/frontend/monitoring/components/charts/options_spec.js
index 1c8fdc01e3e..3372d27e4f9 100644
--- a/spec/frontend/monitoring/components/charts/options_spec.js
+++ b/spec/frontend/monitoring/components/charts/options_spec.js
@@ -1,5 +1,9 @@
 import { SUPPORTED_FORMATS } from '~/lib/utils/unit_format';
-import { getYAxisOptions, getTooltipFormatter } from '~/monitoring/components/charts/options';
+import {
+  getYAxisOptions,
+  getTooltipFormatter,
+  getValidThresholds,
+} from '~/monitoring/components/charts/options';
 
 describe('options spec', () => {
   describe('getYAxisOptions', () => {
@@ -82,4 +86,242 @@ describe('options spec', () => {
       expect(formatter(1)).toBe('1.000B');
     });
   });
+
+  describe('getValidThresholds', () => {
+    const invalidCases = [null, undefined, NaN, 'a string', true, false];
+
+    let thresholds;
+
+    afterEach(() => {
+      thresholds = null;
+    });
+
+    it('returns same thresholds when passed values within range', () => {
+      thresholds = getValidThresholds({
+        mode: 'absolute',
+        range: { min: 0, max: 100 },
+        values: [10, 50],
+      });
+
+      expect(thresholds).toEqual([10, 50]);
+    });
+
+    it('filters out thresholds that are out of range', () => {
+      thresholds = getValidThresholds({
+        mode: 'absolute',
+        range: { min: 0, max: 100 },
+        values: [-5, 10, 110],
+      });
+
+      expect(thresholds).toEqual([10]);
+    });
+    it('filters out duplicate thresholds', () => {
+      thresholds = getValidThresholds({
+        mode: 'absolute',
+        range: { min: 0, max: 100 },
+        values: [5, 5, 10, 10],
+      });
+
+      expect(thresholds).toEqual([5, 10]);
+    });
+
+    it('sorts passed thresholds and applies only the first two in ascending order', () => {
+      thresholds = getValidThresholds({
+        mode: 'absolute',
+        range: { min: 0, max: 100 },
+        values: [10, 1, 35, 20, 5],
+      });
+
+      expect(thresholds).toEqual([1, 5]);
+    });
+
+    it('thresholds equal to min or max are filtered out', () => {
+      thresholds = getValidThresholds({
+        mode: 'absolute',
+        range: { min: 0, max: 100 },
+        values: [0, 100],
+      });
+
+      expect(thresholds).toEqual([]);
+    });
+
+    it.each(invalidCases)('invalid values for thresholds are filtered out', invalidValue => {
+      thresholds = getValidThresholds({
+        mode: 'absolute',
+        range: { min: 0, max: 100 },
+        values: [10, invalidValue],
+      });
+
+      expect(thresholds).toEqual([10]);
+    });
+
+    describe('range', () => {
+      it('when range is not defined, empty result is returned', () => {
+        thresholds = getValidThresholds({
+          mode: 'absolute',
+          values: [10, 20],
+        });
+
+        expect(thresholds).toEqual([]);
+      });
+
+      it('when min is not defined, empty result is returned', () => {
+        thresholds = getValidThresholds({
+          mode: 'absolute',
+          range: { max: 100 },
+          values: [10, 20],
+        });
+
+        expect(thresholds).toEqual([]);
+      });
+
+      it('when max is not defined, empty result is returned', () => {
+        thresholds = getValidThresholds({
+          mode: 'absolute',
+          range: { min: 0 },
+          values: [10, 20],
+        });
+
+        expect(thresholds).toEqual([]);
+      });
+
+      it('when min is larger than max, empty result is returned', () => {
+        thresholds = getValidThresholds({
+          mode: 'absolute',
+          range: { min: 100, max: 0 },
+          values: [10, 20],
+        });
+
+        expect(thresholds).toEqual([]);
+      });
+
+      it.each(invalidCases)(
+        'when min has invalid value, empty result is returned',
+        invalidValue => {
+          thresholds = getValidThresholds({
+            mode: 'absolute',
+            range: { min: invalidValue, max: 100 },
+            values: [10, 20],
+          });
+
+          expect(thresholds).toEqual([]);
+        },
+      );
+
+      it.each(invalidCases)(
+        'when max has invalid value, empty result is returned',
+        invalidValue => {
+          thresholds = getValidThresholds({
+            mode: 'absolute',
+            range: { min: 0, max: invalidValue },
+            values: [10, 20],
+          });
+
+          expect(thresholds).toEqual([]);
+        },
+      );
+    });
+
+    describe('values', () => {
+      it('if values parameter is omitted, empty result is returned', () => {
+        thresholds = getValidThresholds({
+          mode: 'absolute',
+          range: { min: 0, max: 100 },
+        });
+
+        expect(thresholds).toEqual([]);
+      });
+
+      it('if there are no values passed, empty result is returned', () => {
+        thresholds = getValidThresholds({
+          mode: 'absolute',
+          range: { min: 0, max: 100 },
+          values: [],
+        });
+
+        expect(thresholds).toEqual([]);
+      });
+
+      it.each(invalidCases)(
+        'if invalid values are passed, empty result is returned',
+        invalidValue => {
+          thresholds = getValidThresholds({
+            mode: 'absolute',
+            range: { min: 0, max: 100 },
+            values: [invalidValue],
+          });
+
+          expect(thresholds).toEqual([]);
+        },
+      );
+    });
+
+    describe('mode', () => {
+      it.each(invalidCases)(
+        'if invalid values are passed, empty result is returned',
+        invalidValue => {
+          thresholds = getValidThresholds({
+            mode: invalidValue,
+            range: { min: 0, max: 100 },
+            values: [10, 50],
+          });
+
+          expect(thresholds).toEqual([]);
+        },
+      );
+
+      it('if mode is not passed, empty result is returned', () => {
+        thresholds = getValidThresholds({
+          range: { min: 0, max: 100 },
+          values: [10, 50],
+        });
+
+        expect(thresholds).toEqual([]);
+      });
+
+      describe('absolute mode', () => {
+        it('absolute mode behaves correctly', () => {
+          thresholds = getValidThresholds({
+            mode: 'absolute',
+            range: { min: 0, max: 100 },
+            values: [10, 50],
+          });
+
+          expect(thresholds).toEqual([10, 50]);
+        });
+      });
+
+      describe('percentage mode', () => {
+        it('percentage mode behaves correctly', () => {
+          thresholds = getValidThresholds({
+            mode: 'percentage',
+            range: { min: 0, max: 1000 },
+            values: [10, 50],
+          });
+
+          expect(thresholds).toEqual([100, 500]);
+        });
+
+        const outOfPercentBoundsValues = [-1, 0, 100, 101];
+        it.each(outOfPercentBoundsValues)(
+          'when values out of 0-100 range are passed, empty result is returned',
+          invalidValue => {
+            thresholds = getValidThresholds({
+              mode: 'percentage',
+              range: { min: 0, max: 1000 },
+              values: [invalidValue],
+            });
+
+            expect(thresholds).toEqual([]);
+          },
+        );
+      });
+    });
+
+    it('calling without passing object parameter returns empty array', () => {
+      thresholds = getValidThresholds();
+
+      expect(thresholds).toEqual([]);
+    });
+  });
 });