test for helpers/api/general

app/helpers/api/general.test.ts

@@ -0,0 +1,90 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+import {debounce} from './general';
+
+describe('helpers/api/general', () => {
+    beforeEach(() => {
+        jest.useFakeTimers();
+    });
+
+    afterEach(() => {
+        jest.useRealTimers();
+    });
+    describe('debounce', () => {
+        test('should debounce function calls', () => {
+            const func = jest.fn();
+            const debouncedFunc = debounce(func, 100);
+
+            // Call debounced function multiple times
+            debouncedFunc();
+            debouncedFunc();
+            debouncedFunc();
+
+            // Function should not have been called yet
+            expect(func).not.toHaveBeenCalled();
+
+            // Fast forward time
+            jest.runAllTimers();
+
+            // Function should have been called once
+            expect(func).toHaveBeenCalledTimes(1);
+        });
+
+        test('should execute callback after debounced function', () => {
+            const func = jest.fn();
+            const callback = jest.fn();
+            const debouncedFunc = debounce(func, 100, false, callback);
+
+            debouncedFunc();
+
+            // Neither function should have been called yet
+            expect(func).not.toHaveBeenCalled();
+            expect(callback).not.toHaveBeenCalled();
+
+            // Fast forward time
+            jest.runAllTimers();
+
+            // Both functions should have been called once
+            expect(func).toHaveBeenCalledTimes(1);
+            expect(callback).toHaveBeenCalledTimes(1);
+        });
+
+        test('should execute immediately when immediate flag is true', () => {
+            const func = jest.fn();
+            const callback = jest.fn();
+            const debouncedFunc = debounce(func, 100, true, callback);
+
+            debouncedFunc();
+
+            // Both functions should be called immediately
+            expect(func).toHaveBeenCalledTimes(1);
+            expect(callback).toHaveBeenCalledTimes(1);
+
+            // Call it again immediately
+            debouncedFunc();
+
+            // Should not call again immediately
+            expect(func).toHaveBeenCalledTimes(1);
+            expect(callback).toHaveBeenCalledTimes(1);
+
+            // Fast forward time
+            jest.runAllTimers();
+
+            // Counts should remain the same
+            expect(func).toHaveBeenCalledTimes(1);
+            expect(callback).toHaveBeenCalledTimes(1);
+        });
+
+        test('should pass arguments to the debounced function', () => {
+            const func = jest.fn();
+            const debouncedFunc = debounce(func, 100);
+            const args = ['arg1', 'arg2'];
+
+            debouncedFunc(...args);
+            jest.runAllTimers();
+
+            expect(func).toHaveBeenCalledWith(...args);
+        });
+    });
+});