Supports `buffer` and `offset` in `Array#pack`

* pack.c (pack_pack): Supports `buffer` and `offset` in `Array#pack`.
  [Feature #12754] [ruby-dev:49798]


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@56957 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 34 insertions, 0 deletions

diff --git a/test/ruby/test_pack.rb b/test/ruby/test_pack.rb
index c5af6f2152..415dc78e60 100644
--- a/test/ruby/test_pack.rb
+++ b/test/ruby/test_pack.rb
@@ -812,4 +812,38 @@ EXPECTED
       assert_raise_with_message(ArgumentError, /too few/) {ary.pack("AA")}
     end;
   end
+
+  def test_pack_with_buffer
+    buf = String.new(capacity: 100)
+
+    assert_raise_with_message(ArgumentError, /without buffer/) {
+      [0xDEAD_BEEF].pack('N', offset: 10)
+    }
+    assert_raise_with_message(ArgumentError, /too small/) {
+      [0xDEAD_BEEF].pack('N', buffer: buf, offset: 200)
+    }
+    assert_raise_with_message(RuntimeError, /frozen/) {
+      [0xDEAD_BEEF].pack('N', buffer: 'foo'.freeze)
+    }
+    assert_raise_with_message(TypeError, /into Integer/) {
+      [0xDEAD_BEEF].pack('N', buffer: buf, offset: '10')
+    }
+    assert_raise_with_message(TypeError, /must be String/) {
+      [0xDEAD_BEEF].pack('N', buffer: Object.new)
+    }
+
+    addr = [buf].pack('p')
+
+    [0xDEAD_BEEF].pack('N', buffer: buf)
+    assert_equal "\xDE\xAD\xBE\xEF", buf
+
+    [0xBABE_F00D].pack('N', buffer: buf, offset: 4)
+    assert_equal "\xDE\xAD\xBE\xEF\xBA\xBE\xF0\x0D", buf
+    assert_equal addr, [buf].pack('p')
+
+    [0xBAAD_FACE].pack('N', buffer: buf, offset: 10)
+    assert_equal "\xDE\xAD\xBE\xEF\xBA\xBE\xF0\x0D\0\0\xBA\xAD\xFA\xCE", buf
+
+    assert_equal addr, [buf].pack('p')
+  end
 end