初始化

client/test/memoryhelper.test.js

@@ -0,0 +1,67 @@
+import { 
+  MemoryHelper
+} from "../src/memoryhelper.js";
+
+describe(`MemoryHelper.writeSingleBit`, () => {
+  test('turn on with offset 0', () => {
+    let bytes = new ArrayBuffer(3);
+    MemoryHelper.writeSingleBit(bytes, 0, false);
+
+    // check 00 00 00
+    const view = new Uint8Array(bytes);
+    expect(view[0]).toBe(0);
+    expect(view[1]).toBe(0);
+    expect(view[2]).toBe(0);
+  });
+  test('turn off with offset 0', () => {
+    let bytes = new ArrayBuffer(3);
+    MemoryHelper.writeSingleBit(bytes, 0, true);
+
+    // check 00 00 01
+    const view = new Uint8Array(bytes);
+    expect(view[0]).toBe(1);
+    expect(view[1]).toBe(0);
+    expect(view[2]).toBe(0);
+
+    MemoryHelper.writeSingleBit(bytes, 0, false);
+
+    // check 00 00 00
+    expect(view[0]).toBe(0);
+    expect(view[1]).toBe(0);
+    expect(view[2]).toBe(0);
+  });
+  test('turn on with offset 32', () => {
+    let bytes = new ArrayBuffer(3);
+    MemoryHelper.writeSingleBit(bytes, 8, true);
+
+    // check 00 01 00
+    const view = new Uint8Array(bytes);
+    expect(view[0]).toBe(0);
+    expect(view[1]).toBe(1);
+    expect(view[2]).toBe(0);
+
+    MemoryHelper.writeSingleBit(bytes, 0, true);
+
+    // check 00 01 01
+    expect(view[0]).toBe(1);
+    expect(view[1]).toBe(1);
+    expect(view[2]).toBe(0);
+  });
+  test('turn on with offset 15', () => {
+    let bytes = new ArrayBuffer(3);
+    MemoryHelper.writeSingleBit(bytes, 15, true);
+
+    // check 00 80 00
+    const view = new Uint8Array(bytes);
+    expect(view[0]).toBe(0);
+    expect(view[1]).toBe(128);
+    expect(view[2]).toBe(0);
+
+    MemoryHelper.writeSingleBit(bytes, 15, false);
+
+    // check 00 00 00
+    expect(view[0]).toBe(0);
+    expect(view[1]).toBe(0);
+    expect(view[2]).toBe(0);
+  });  
+});