Description

Add support for Span and ReadOnlySpan. Though they do not directly implement IEnumerable<T> interface it would be nice to be able to assert using NotContain etc.

Complete minimal example reproducing the issue

// Arrange
ReadOnlySpan<string> span = new ReadOnlySpan<string>(new[] {"a", "b", "c"});

// Act
span = span.Slice(1);

// Assert
span.Should().NotContain("a");

Expected behavior:

Test should pass.

Actual behavior:

Compilation error saying extension method Should does not exist for ReadOnlySpan.

Versions

• Which version of Fluent Assertions are you using? 5.4.1
• Which .NET runtime and version are you targeting? .NET Core 2.1.