The internal method BeInOrder does not cater for duplicate values.
An array like this {1, 6 12, 12, 15 ,17, 26}
Reports that the item at index 2 is in the wrong order. Looking at the code I can see this is because the comparison of items is done with
int indexOfActualItem = Array.IndexOf(actualItems, orderedItem);
Which of course is going to return 2 for both instances of 12.
Comments: Fixed in commit https://fluentassertions.codeplex.com/SourceControl/changeset/23647ff8786a7cabfd0974d3dcefb6b123722f41. The assertion itself was correctly implemented, but the index reported was wrong.
An array like this {1, 6 12, 12, 15 ,17, 26}
Reports that the item at index 2 is in the wrong order. Looking at the code I can see this is because the comparison of items is done with
int indexOfActualItem = Array.IndexOf(actualItems, orderedItem);
Which of course is going to return 2 for both instances of 12.
Comments: Fixed in commit https://fluentassertions.codeplex.com/SourceControl/changeset/23647ff8786a7cabfd0974d3dcefb6b123722f41. The assertion itself was correctly implemented, but the index reported was wrong.