Improve readability of assertion failure messages

[vbreuss]

Fixes #764 as also discussed in this comment by

• Moving the assertion expression at the end
• Replacing the GetFailureMessage with GetExpectation which returns only the expectation from the BaseAssertCondition
• Replacing the Passes method with GetResult which returns not only a boolean value, but an AssertionResult which also contains the failure message.

This allows the assertion message to be combined to read like an english sentence, e.g.
instead of

Assert.That(myClass).HasMember(x => x.Nested.Nested.Nested.Number).EqualTo(1)
MyClass.Number:
    Expected: 1
    Received: 123

it would read

Expected myClass MyClass.Number to be equal to 1, but received 123.
At Assert.That(myClass).HasMember(x => x.Nested.Nested.Nested.Number).EqualTo(1)

Also added some tests for correctly throwing exceptions (see #294) where the new output reads e.g.

Expected action to have Message equal to "Fails_For_Some_Other_Reason", but it differs at index 10:
              ↓
   "Fails_For_Exceptions_With_Different_Message"
   "Fails_For_Some_Other_Reason"
              ↑.
At Assert.That(action).ThrowsException.With.Message.EqualTo("Fails_For_Some_Other_Reason", StringCompar...

[vbreuss]

@thomhurst : I don't understand why the pipeline fails.
Locally all unit tests compile and succeed, but on the pipeline the TimeoutTests5 fail 🙈

[thomhurst]

@thomhurst : I don't understand why the pipeline fails. Locally all unit tests compile and succeed, but on the pipeline the TimeoutTests5 fail 🙈

It looks like one of the assertions has broken. If you go to the pipeline output, then scroll above the table you can expand each step to see it's full output.

I'm seeing this:

failed MatrixTest(2) (46ms)
    Expected value to be equal to 1
     or
    to be equal to 2
     or
    to be equal to 3, but the received value 2 is different and the received value
  2 is different.
    At Assert.That(value).IsEqualTo(1).Or.IsEqualTo(2).Or.IsEqualTo(3)

[thomhurst]

Does this need to take a func? Looks like it invokes it immediately. Couldn't you just pass in the boolean result directly?

[vbreuss]

I could probably get rid of it here, but not in the OrFailIf method, as it would then throw, e.g. in

		=> AssertionResult
			.FailIf(
				() => actualValue is null,
				$"{ActualExpression ?? typeof(TActual).Name} is null")
			.OrFailIf(
				() => actualValue.Contains(inner, equalityComparer),
				"it was found in the collection");

because both conditions are always evaluated and not just when all previous conditions didn't fail.
However having different method signatures for FailIf and OrFailIf looks strange to me...

[thomhurst]

Any reason for the tab increase?

[vbreuss]

No, it seems I got somehow tabs mixed within. Will have a general look at my files to use consistently spaces, as in the other files...

[thomhurst]

Thanks @vbreuss !