public async Task TestThreadSafety() { int flag1 = 0; Assert.True(ThreadSafety.FlipToTrue(ref flag1)); Assert.Equal(1, flag1); Assert.False(ThreadSafety.FlipToTrue(ref flag1)); Assert.Equal(1, flag1); Assert.True(ThreadSafety.FlipToFalse(ref flag1)); Assert.Equal(0, flag1); Assert.False(ThreadSafety.FlipToFalse(ref flag1)); Assert.Equal(0, flag1); }