Added Unit Test for Swap-Source.ts

Author: silky-x0

src/sources/swap-source.test.ts

@@ -0,0 +1,126 @@
+import type { Observable } from 'rxjs';
+
+import { Subject } from 'rxjs';
+import { MockElement, MockEvent } from '../test-support';
+import { Swap, swap } from './swap-source';
+
+describe('Swap Event Adapter', () => {
+
+    it('Swaps a value in an element with a static string', () => {
+        const oldValue = 'old data';
+        const newValue = 'new data';
+
+        const el = MockElement({
+            tagName: 'INPUT',
+            type: 'text',
+            value: oldValue,
+        });
+
+        const eventData = MockEvent('input', {
+            target: el as HTMLInputElement
+        });
+
+        const handlerSpy = jest.fn();
+        const source = Swap(newValue)(handlerSpy);
+        source.next(eventData);
+
+        expect(handlerSpy).toHaveBeenCalledWith(oldValue);
+        expect(el.value).toEqual(newValue);
+    });
+
+    it('Swaps a value in an element using a function', () => {
+        const oldValue = 'old data';
+
+        const el = MockElement({
+            tagName: 'INPUT',
+            type: 'text',
+            value: oldValue,
+        });
+
+        const eventData = MockEvent('input', {
+            target: el as HTMLInputElement
+        });
+
+        const replaceFn = (v: string) => v.toUpperCase();
+
+        const handlerSpy = jest.fn();
+        const source = Swap(replaceFn)(handlerSpy);
+        source.next(eventData);
+
+        expect(handlerSpy).toHaveBeenCalledWith(oldValue);
+        expect(el.value).toEqual('OLD DATA');
+    });
+
+    it('Swaps a value in an element with empty string by default', () => {
+        const oldValue = 'old data';
+
+        const el = MockElement({
+            tagName: 'INPUT',
+            type: 'text',
+            value: oldValue,
+        });
+
+        const eventData = MockEvent('input', {
+            target: el as HTMLInputElement
+        });
+
+        const handlerSpy = jest.fn();
+        const source = Swap()(handlerSpy);
+        source.next(eventData);
+
+        expect(handlerSpy).toHaveBeenCalledWith(oldValue);
+        expect(el.value).toEqual('');
+    });
+
+});
+
+describe('swap Event Operator', () => {
+
+    it('Swaps and emits a value from an element with static string', () => {
+        const oldValue = 'old data';
+        const newValue = 'new data';
+
+        const el = MockElement({
+            tagName: 'INPUT',
+            type: 'text',
+            value: oldValue,
+        });
+
+        const eventData = MockEvent('input', {
+            target: el as HTMLInputElement
+        });
+
+        const handlerSpy = jest.fn();
+        const pipeline = new Subject<typeof eventData>().pipe(swap(newValue)) as Observable<string> & Subject<typeof eventData>;
+        pipeline.subscribe(x => handlerSpy(x));
+        pipeline.next(eventData);
+
+        expect(handlerSpy).toHaveBeenCalledWith(oldValue);
+        expect(el.value).toEqual(newValue);
+    });
+
+    it('Swaps and emits a value from an element using function', () => {
+        const oldValue = 'old data';
+
+        const el = MockElement({
+            tagName: 'INPUT',
+            type: 'text',
+            value: oldValue,
+        });
+
+        const eventData = MockEvent('input', {
+            target: el as HTMLInputElement
+        });
+
+        const replaceFn = (v: string) => v.toUpperCase();
+
+        const handlerSpy = jest.fn();
+        const pipeline = new Subject<typeof eventData>().pipe(swap(replaceFn)) as Observable<string> & Subject<typeof eventData>;
+        pipeline.subscribe(x => handlerSpy(x));
+        pipeline.next(eventData);
+
+        expect(handlerSpy).toHaveBeenCalledWith(oldValue);
+        expect(el.value).toEqual('OLD DATA');
+    });
+
+});