Fixed Array#pack's handling of the 'h'/'H' formats.

kernel/common/pack.rb

@@ -197,13 +197,35 @@ def hex_string(kind, t)
     item = "" if item.nil?
 
     size = parse_tail(t, kind, item.length)
-    str = item.scan(/..?/).first(size)
+    str = item[0, size].scan(/..?/)
 
-    @result << if kind == "h" then
-                 str.map { |b| b.reverse.hex.chr }.join
-               else
-                 str.map { |b| b.        hex.chr }.join
-               end
+    numbers = if kind == "h" then
+                str.map { |b| b.reverse.hex }
+              else
+                str.map { |b| b.        hex }
+              end
+
+    if kind == 'H' && !numbers.empty? && numbers.last < 16
+      numbers[-1] *= 16
+    end
+
+    diff = size - item.length
+
+    if diff > 0
+      # we couldn't read as much data as was requested,
+      # so we'll make up for that with a couple of zeroes.
+      if (item.length % 2) == 0
+        left = (diff / 2.0 + 0.5).to_i
+      else
+        left = diff / 2
+      end
+
+      left.times do
+        numbers << 0
+      end
+    end
+
+    @result << numbers.map { |n| n.chr }.join
   end
 
   def decimal(kind, t)

spec/tags/frozen/core/array/pack_tags.txt

@@ -1,16 +1,3 @@
-fails:Array#pack with format 'H' encodes hexadecimal digits to byte sequence in the order of high-nibble first
-fails:Array#pack with format 'H' ignores rest of the pack argument when the argument is too long
-fails:Array#pack with format 'H' fills low-nibble of the last byte with 0 when count is odd
-fails:Array#pack with format 'H' fills the rest bytes with 0 if pack argument has insufficient length
-fails:Array#pack with format 'H' fills low-nibble of the last byte with 0 when count is odd even if pack argument has insufficient length
-fails:Array#pack with format 'H' considers count = 1 if count omited
-fails:Array#pack with format 'H' consumes only one array item per a format
-fails:Array#pack with format 'h' ignores rest of the pack argument when the argument is too long
-fails:Array#pack with format 'h' fills low-nibble of the last byte with 0 when count is odd
-fails:Array#pack with format 'h' fills the rest bytes with 0 if pack argument has insufficient length
-fails:Array#pack with format 'h' fills high-nibble of the last byte with 0 when count is odd even if pack argument has insufficient length
-fails:Array#pack with format 'h' considers count = 1 if count omited
-fails:Array#pack with format 'h' consumes only one array item per a format
 fails:Array#pack with format 'n' regards negative values as 2's complement in order to converts it to positive
 fails:Array#pack with format 'N' regards negative values as 2's complement in order to converts it to positive
 fails:Array#pack with format 'q' returns a string containing 8 bytes for an integer