test: add tests for isInCurrentMonth

src/date-picker/date-picker.ts

@@ -16,7 +16,7 @@ import { adjustOutOfRangeValue } from '../helpers/adjust-out-of-range-value.js';
 import { dateValidator } from '../helpers/date-validator.js';
 import { dispatchCustomEvent } from '../helpers/dispatch-custom-event.js';
 import { focusElement } from '../helpers/focus-element.js';
-import { isInTargetMonth } from '../helpers/is-in-current-month.js';
+import { isInCurrentMonth } from '../helpers/is-in-current-month.js';
 import { splitString } from '../helpers/split-string.js';
 import { toDateString } from '../helpers/to-date-string.js';
 import { toFormatters } from '../helpers/to-formatters.js';
@@ -190,8 +190,8 @@ export class DatePicker extends DatePickerMixin(DatePickerMinMaxMixin(LitElement
       if (changedProperties.has('_currentDate') && this.#shouldUpdateFocusInNavigationButtons) {
         const currentDate = this._currentDate;
 
-        isInTargetMonth(this._min, currentDate) && focusElement(this._navigationNext);
-        isInTargetMonth(this._max, currentDate) && focusElement(this._navigationPrevious);
+        isInCurrentMonth(this._min, currentDate) && focusElement(this._navigationNext);
+        isInCurrentMonth(this._max, currentDate) && focusElement(this._navigationPrevious);
 
         this.#shouldUpdateFocusInNavigationButtons = false;
       }
@@ -234,8 +234,8 @@ export class DatePicker extends DatePickerMixin(DatePickerMinMaxMixin(LitElement
           nothing :
           html`
           <div class=month-pagination>
-            ${this.#renderNavigationButton('previous', !isInTargetMonth(min, currentDate))}
-            ${this.#renderNavigationButton('next', !isInTargetMonth(max, currentDate))}
+            ${this.#renderNavigationButton('previous', !isInCurrentMonth(min, currentDate))}
+            ${this.#renderNavigationButton('next', !isInCurrentMonth(max, currentDate))}
           </div>
           `
       }

src/helpers/is-in-current-month.ts

@@ -1,4 +1,4 @@
-export function isInTargetMonth(targetDate: Date, sourceDate: Date): boolean {
+export function isInCurrentMonth(targetDate: Date, sourceDate: Date): boolean {
   const targetDateFy = targetDate.getUTCFullYear();
   const targetDateM = targetDate.getUTCMonth();
   const sourceDateFY = sourceDate.getUTCFullYear();

src/month-calendar/month-calendar.ts

@@ -9,7 +9,7 @@ import { navigationKeySetGrid } from '../constants.js';
 import { computeNextSelectedDate } from '../helpers/compute-next-selected-date.js';
 import { dispatchCustomEvent } from '../helpers/dispatch-custom-event.js';
 import { focusElement } from '../helpers/focus-element.js';
-import { isInTargetMonth } from '../helpers/is-in-current-month.js';
+import { isInCurrentMonth } from '../helpers/is-in-current-month.js';
 import { toClosestTarget } from '../helpers/to-closest-target.js';
 import { toResolvedDate } from '../helpers/to-resolved-date.js';
 import { keyHome } from '../key-values.js';
@@ -106,7 +106,7 @@ export class MonthCalendar extends LitElement implements MonthCalendarProperties
        * When there is a selected date in the current month, tab to focus on selected date.
        * Otherwise, set the first day of month tabbable so that tapping on Tab focuses that.
        */
-      const tabbableDate = isInTargetMonth(date, currentDate) ?
+      const tabbableDate = isInCurrentMonth(date, currentDate) ?
         date :
         computeNextSelectedDate({
           currentDate,

src/tests/helpers/is-in-current-month.test.ts

@@ -0,0 +1,34 @@
+import { expect } from '@open-wc/testing';
+
+import { isInCurrentMonth } from '../../helpers/is-in-current-month';
+import { messageFormatter } from '../test-utils/message-formatter';
+
+type A = [Date, Date, boolean];
+
+const cases: A[] = [
+  [
+    new Date('2020-02-02'),
+    new Date('2020-02-12'),
+    true,
+  ],
+  [
+    new Date('2020-02-02'),
+    new Date('2020-03-12'),
+    false,
+  ],
+];
+
+describe(isInCurrentMonth.name, () => {
+  cases.forEach(a => {
+    it(
+      messageFormatter('returns if %s is current month of %s', a),
+      () => {
+        const [testTarget, testSource, expected] = a;
+
+        const result = isInCurrentMonth(testTarget, testSource);
+
+        expect(result).equal(expected);
+      }
+    );
+  });
+});