Case insensitive comparison in Contains under nUnit

Question

I'm trying to assert that a list contains a certain string. Since I'd need the condition to be evaluated case insensitively, I used a workaround (something along this blog post). However, I'd like to know why there seems not to be a way to make the Assert.Contains method perform the comparison without regard of case sensitivity. Or is there a way to do that? (When I googled it, I only got hits on constraints for the Assert.That method on the official page for nUnit.)

Accepted Answer

There is no way to specify ignoreCase in the `Assert.Contains`. Whether it's something that is overlooked or intended I do not know. You can, however, use

```
StringAssert.AreEqualIgnoringCase(left, right);
```

in your unit tests to achieve the same results.

Alternatively, if you wish to stick with the `Assert.Foo()` "theme", you could do something like this:

```
Assert.IsTrue(string.Equals(left, right, StringComparison.OrdinalIgnoreCase));
```

or, since `Contains` treats arrays:

```
Assert.IsTrue(list.Any(element => element.ToUpper() == "VILTERSTEN"));
```

where you call `ToUpper()` on both the left and right string operands, which effectively makes the comparison ignore case as well. `OrdinalIgnoreCase` is to ensure some corner cases (read: Turkish) of cultures do not cause unexpected results. If you are interested in reading up on that, have a look at the Turkey test.

Case insensitive comparison in Contains under nUnit

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