FixedLengthTruncator throws exception in some cases

[bambuca]

"Short".Truncate(100, null); will throw exception:

In the Truncate method this code casues error, because value is shorter than lenght and thus value.Substring(0, legth) throws exception

https://github.com/Humanizr/Humanizer/blob/main/src/Humanizer/Truncation/FixedLengthTruncator.cs , line 21-26
if (truncationString == null || truncationString.Length > length)
{
return truncateFrom == TruncateFrom.Right
? value.Substring(0, length)
: value.Substring(value.Length - length);
}

[hangy]

Do you have a short repro for this? "Short".Truncate(100, null) doesn't even compile for me, as the overloads are ambiguous. "Short".Truncate(100) correctly returns "Short". There are actually test cases for a case when the input string is shorter than the length.

[bambuca]

Sorry, my bad. The null parameter should be (string)null. See here https://dotnetfiddle.net/qZcZ7f

In FixedLengthTruncator.cs, you correctly check if (value.Length > length) in most cases. However, this check is missing when truncationString == null. In that case, you call value.Substring(0, length), which can fail if value is shorter than the specified length.

I crated PR for that #1547