public async void ReadJSDataAsStreamAsync_ThrowsNotSupportedException() { // Arrange var runtime = new TestJSRuntime(); var dataReference = new JSStreamReference(runtime, 10, 10); // Act var exception = await Assert.ThrowsAsync <NotSupportedException>(async() => await runtime.ReadJSDataAsStreamAsync(dataReference, 10, CancellationToken.None)); // Assert Assert.Equal("The current JavaScript runtime does not support reading data streams.", exception.Message); }