Adds unit tests for keybinding.js

src/tests/lib/keybinding.test.js

@@ -0,0 +1,158 @@
+import { describe, it, expect, beforeEach, afterEach, vi } from 'vitest';
+import { keybinding } from '$lib/keybinding';
+
+describe('keybinding action', () => {
+    let node;
+    let mockWindow;
+    let currentHandler;
+
+    beforeEach(() => {
+        node = {
+            click: vi.fn()
+        };
+
+        mockWindow = {
+            addEventListener: vi.fn((event, handler) => {
+                if (event === 'keydown') {
+                    currentHandler = handler;
+                }
+            }),
+            removeEventListener: vi.fn((event, handler) => {
+                if (event === 'keydown' && handler === currentHandler) {
+                    currentHandler = null;
+                }
+            })
+        };
+
+        // Set up mock window
+        const originalWindow = global.window;
+        global.window = mockWindow;
+
+        beforeEach.cleanup = () => {
+            global.window = originalWindow;
+        };
+    });
+
+    afterEach(() => {
+        beforeEach.cleanup?.();
+        vi.clearAllMocks();
+        currentHandler = null;
+    });
+
+    const triggerKeydown = (keyParams) => {
+        const event = {
+            code: keyParams.code || '',
+            altKey: keyParams.alt || false,
+            shiftKey: keyParams.shift || false,
+            ctrlKey: keyParams.control || false,
+            metaKey: keyParams.control || false,
+            preventDefault: vi.fn()
+        };
+
+        if (currentHandler) {
+            currentHandler(event);
+        }
+        return event;
+    };
+
+    it('adds keydown event listener on initialization', () => {
+        keybinding(node, { code: 'KeyA' });
+        expect(mockWindow.addEventListener).toHaveBeenCalledWith('keydown', expect.any(Function));
+    });
+
+    it('removes existing listener before adding new one on update', () => {
+        let params = { code: 'KeyA' };
+        const action = keybinding(node, params);
+
+        // Clear the initial setup calls
+        mockWindow.addEventListener.mockClear();
+        mockWindow.removeEventListener.mockClear();
+
+        // Update the params object directly
+        params.code = 'KeyB';
+        action.update();
+
+        expect(mockWindow.removeEventListener).toHaveBeenCalledTimes(1);
+        expect(mockWindow.addEventListener).toHaveBeenCalledTimes(1);
+    });
+
+    it('removes listener on destroy', () => {
+        const action = keybinding(node, { code: 'KeyA' });
+        action.destroy();
+
+        expect(mockWindow.removeEventListener).toHaveBeenCalled();
+    });
+
+    it('only responds to matching key code', () => {
+        keybinding(node, { code: 'KeyA' });
+
+        triggerKeydown({ code: 'KeyB' });
+        expect(node.click).not.toHaveBeenCalled();
+
+        triggerKeydown({ code: 'KeyA' });
+        expect(node.click).toHaveBeenCalledTimes(1);
+    });
+
+    it('responds to updated key code', () => {
+        // Create params object that we'll modify
+        let params = { code: 'KeyA' };
+        const action = keybinding(node, params);
+
+        // Verify initial binding works
+        triggerKeydown({ code: 'KeyA' });
+        expect(node.click).toHaveBeenCalledTimes(1);
+
+        // Update params and trigger update
+        node.click.mockClear();
+        params.code = 'KeyB';
+        action.update();
+
+        // Verify new binding works
+        triggerKeydown({ code: 'KeyB' });
+        expect(node.click).toHaveBeenCalledTimes(1);
+
+        // Verify old binding doesn't work
+        node.click.mockClear();
+        triggerKeydown({ code: 'KeyA' });
+        expect(node.click).not.toHaveBeenCalled();
+    });
+
+    it('handles modifier keys correctly', () => {
+        keybinding(node, { 
+            code: 'KeyA',
+            alt: true,
+            shift: true,
+            control: true
+        });
+
+        triggerKeydown({ code: 'KeyA' });
+        expect(node.click).not.toHaveBeenCalled();
+
+        triggerKeydown({ code: 'KeyA', alt: true });
+        expect(node.click).not.toHaveBeenCalled();
+
+        triggerKeydown({ code: 'KeyA', alt: true, shift: true, control: true });
+        expect(node.click).toHaveBeenCalledTimes(1);
+    });
+
+    it('handles meta key as control', () => {
+        keybinding(node, { 
+            code: 'KeyA',
+            control: true
+        });
+
+        const event = triggerKeydown({ code: 'KeyA', control: true });
+        expect(node.click).toHaveBeenCalledTimes(1);
+        expect(event.preventDefault).toHaveBeenCalled();
+    });
+
+    it('triggers callback instead of click when provided', () => {
+        const callback = vi.fn();
+        keybinding(node, { code: 'KeyA', callback });
+
+        triggerKeydown({ code: 'KeyA' });
+
+        expect(callback).toHaveBeenCalledTimes(1);
+        expect(node.click).not.toHaveBeenCalled();
+    });
+});