Add additional jest tests

Add tests for the `omitEmptyProperties` method

Minor refactor of the `omitEmptyProperties` method
and adds some jest tests.

app/assets/javascripts/init_confirm_danger.js

 import Vue from 'vue';
-import { parseBoolean } from './lib/utils/common_utils';
+import { parseBoolean, omitEmptyProperties } from './lib/utils/common_utils';
 import ConfirmDanger from './vue_shared/components/confirm_danger/confirm_danger.vue';
 
-const omitEmptyProperties = (fields) => {
-  return Object.entries(fields).reduce((acc, [key, value]) => {
-    if (value) {
-      return { ...acc, [key]: value };
-    }
-    return acc;
-  }, {});
-};
-
 export default () => {
   const el = document.querySelector('.js-confirm-danger');
   if (!el) return null;

app/assets/javascripts/lib/utils/common_utils.js

@@ -746,3 +746,25 @@ export const isLoggedIn = () => Boolean(window.gon?.current_user_id);
  */
 export const convertArrayOfObjectsToCamelCase = (array) =>
   array.map((o) => convertObjectPropsToCamelCase(o));
+
+/**
+ * This method takes an object and omits any properties
+ * that are null, undefined, false or empty. The returned
+ * object only includes properties that have a `truthy` value.
+ *
+ * @param {Object} obj - Target object to be checked
+ * @returns {Object} Resulting object with only truthy properties
+ */
+export const omitEmptyProperties = (obj = {}) => {
+  const entries = Object.entries(obj);
+  if (!entries.length) {
+    return obj;
+  }
+
+  return entries.reduce((acc, [key, value]) => {
+    if (!value) {
+      return acc;
+    }
+    return { ...acc, [key]: value };
+  }, {});
+};

spec/frontend/lib/utils/common_utils_spec.js

@@ -1051,4 +1051,30 @@ describe('common_utils', () => {
       expect(result).toEqual([{ hello: '' }, { helloWorld: '' }]);
     });
   });
+
+  describe('omitEmptyProperties', () => {
+    let res;
+    const empty = { foo: null, bar: undefined, baz: '', qux: false };
+    const values = { a: 'a', b: 1, c: { d: 'd' }, e: ['f'] };
+
+    beforeEach(() => {
+      res = Object.keys(
+        commonUtils.omitEmptyProperties({
+          ...empty,
+          ...values,
+        }),
+      );
+    });
+
+    it('returns an object with properties that have a value', () => {
+      const valueKeys = Object.keys(values);
+      expect(res).toEqual(valueKeys);
+    });
+
+    it('ignores properties that are empty, nullable or falsy', () => {
+      Object.keys(empty).forEach((key) => {
+        expect(res).not.toContain(key);
+      });
+    });
+  });
 });

spec/frontend/vue_shared/components/confirm_danger/confirm_danger_spec.js

@@ -10,6 +10,7 @@ describe('Confirm Danger Modal', () => {
   const phrase = 'En Taro Adun';
   const buttonText = 'Click me!';
   const buttonClass = 'gl-w-full';
+  const buttonVariant = 'info';
   const modalId = CONFIRM_DANGER_MODAL_ID;
 
   const findBtn = () => wrapper.findComponent(GlButton);
@@ -21,6 +22,7 @@ describe('Confirm Danger Modal', () => {
       propsData: {
         buttonText,
         buttonClass,
+        buttonVariant,
         phrase,
         ...props,
       },
@@ -57,6 +59,10 @@ describe('Confirm Danger Modal', () => {
     expect(findBtn().classes()).toContain(buttonClass);
   });
 
+  it('passes `buttonVariant` prop to button', () => {
+    expect(findBtn().attributes('variant')).toBe(buttonVariant);
+  });
+
   it('will emit `confirm` when the modal confirms', () => {
     expect(wrapper.emitted('confirm')).toBeUndefined();