fails:Array#pack with format 'U' raises a TypeError when passed nil
fails:Array#pack with format 'U' raises a TypeError when passed an Integer
fails:Array#pack with format 'U' ignores whitespace in the format string
fails:Array#pack with format 'U' calls #to_str to coerce the directives string
fails:Array#pack with format 'U' taints the output string if the format string is tainted
fails:Array#pack with format 'U' raises an ArgumentError if there are fewer elements than the format requires
fails:Array#pack with format 'U' encodes ASCII values as a Unicode codepoint
fails:Array#pack with format 'U' encodes UTF-8 BMP codepoints
fails:Array#pack with format 'U' encodes UTF-8 max codepoints
fails:Array#pack with format 'U' encodes values larger than UTF-8 max codepoints
fails:Array#pack with format 'U' encodes the number of array elements specified by the count modifier
fails:Array#pack with format 'U' encodes all remaining elements when passed the '*' modifier
fails:Array#pack with format 'U' calls #to_int to convert the pack argument to an Integer
fails:Array#pack with format 'U' raises a TypeError if #to_int does not return an Integer
fails:Array#pack with format 'U' ignores NULL bytes between directives
fails:Array#pack with format 'U' ignores spaces between directives
fails:Array#pack with format 'U' raises a RangeError if passed a negative number
fails:Array#pack with format 'U' raises a RangeError if passed a number larger than an unsigned 32-bit integer
fails:Array#pack with format 'U' sets the output string to UTF-8 encoding
fails:Array#pack with format 'u' raises a TypeError when passed nil
fails:Array#pack with format 'u' raises a TypeError when passed an Integer
fails:Array#pack with format 'u' ignores whitespace in the format string
fails:Array#pack with format 'u' calls #to_str to coerce the directives string
fails:Array#pack with format 'u' taints the output string if the format string is tainted
fails:Array#pack with format 'u' raises an ArgumentError if there are fewer elements than the format requires
fails:Array#pack with format 'u' encodes an empty string as an empty string
fails:Array#pack with format 'u' appends a newline to the end of the encoded string
fails:Array#pack with format 'u' encodes one element per directive
fails:Array#pack with format 'u' prepends the length of each segment of the input string as the first character (+32) in each line of the output
fails:Array#pack with format 'u' encodes 1, 2, or 3 characters in 4 output characters (uuencoding)
fails:Array#pack with format 'u' emits a newline after complete groups of count / 3 input characters when passed a count modifier
fails:Array#pack with format 'u' implicitly has a count of 45 when passed '*', 0, 1, 2 or no count modifier
fails:Array#pack with format 'u' encodes all ascii characters
fails:Array#pack with format 'u' calls #to_str to convert an object to a String
fails:Array#pack with format 'u' raises a TypeError if #to_str does not return a String
fails:Array#pack with format 'u' raises a TypeError if passed nil
fails:Array#pack with format 'u' raises a TypeError if passed an Integer
fails:Array#pack with format 'u' sets the output string to US-ASCII encoding
