Moq verify with object parameter

.net, c#, moq, unit-testing

Solution

The first attempt is closer to what you want to achieve.

The reason it fails is that Moq (probably) uses `Object.Equals` under the cover to test if the `ImageFilterOptions` parameter that the method was called with is the same instance as the one you supplied in the call to `Verify`.

It is impossible for them to be the same instance, because in `Verify` you create a `new ImageFilterOptions()`.

Instead of performing the parameter check this way, you could use Moq's `It.Is` syntax to provide an expression that verifies the parameter was the expected one.

In your case, you want to check that the parameter is of type `ImageFilterOptions` and that both the `Width` and the `Height` are set to `256`. The expression that allows you to do that is:

It.Is<ImageFilterOptions>(p => p.Width == 256 && p.Height == 256)

So, your call to `Verify` could look like this:

this.MockImageResizeFilter.Verify(m => m.Filter(
            this.UploadedFileData,
            It.Is<ImageFilterOptions>(p => p.Width == 256 && p.Height == 256)));

Problem

I am trying to verify a parameter that is a class. The code being tested is fine. The bug is in the test. I have tried two methods, both of which have failed. Here are my attempts: 1: ``` this.MockImageResizeFilter.Verify(m => m.Filter(this.UploadedFileData, new ImageFilterOptions() { Width = 256, Height = 256, })); ``` This always fails, even though an object passed as the second parameter has equal properties. The first parameter is verified fine. 2: ``` this.MockImageResizeFilter.Setup(m => m.Filter(It.IsAny<byte[]>(), It.IsAny<ImageFilterOptions>())) .Callback<byte[], ImageFilterOptions>((data, options) => { Assert.AreEqual(this.UploadedFileData, data, "data"); Assert.AreEqual(filterOptions.Width, options.Width, "Width"); Assert.AreEqual(filterOptions.Height, options.Height, "Height"); } ); ``` This always passes, even when it should fail. The Asserts in the callback do fail, but the exception is not passed to the outer context, and thus the test always passes. Can you help me find what I am doing wrong?

Original source