wrap trailer parsing API

Author: brianmario

ext/rugged/rugged_commit.c

@@ -7,6 +7,7 @@
 
 #include "rugged.h"
 #include "git2/commit.h"
+#include "git2/message.h"
 
 extern VALUE rb_mRugged;
 extern VALUE rb_cRuggedObject;
@@ -44,6 +45,69 @@ static VALUE rb_git_commit_message_GET(VALUE self)
 	return rb_enc_str_new(message, strlen(message), encoding);
 }
 
+struct trailer_cb_info {
+	VALUE trailers;
+	rb_encoding *encoding;
+};
+
+static int rb_each_trailer(const char *key, const char *value, void *payload)
+{
+	struct trailer_cb_info *cb_info = (struct trailer_cb_info *)payload;
+
+	VALUE pair = rb_ary_new();
+
+	// trailer key
+	rb_ary_push(pair, rb_enc_str_new(key, strlen(key), cb_info->encoding));
+
+	// trailer value
+	rb_ary_push(pair, rb_enc_str_new(value, strlen(value), cb_info->encoding));
+
+	// add it to the list
+	rb_ary_push(cb_info->trailers, pair);
+
+	return GIT_OK;
+}
+
+/*
+ *  call-seq:
+ *    commit.trailers -> [["Trailer-name", "trailer value"], ...]
+ *
+ *  Return an array of arrays, each of which is a key/value pair representing a
+ *  commit message trailer. Both the keys and values will be strings. An array
+ *  is used to preserve the order the trailers were found.
+ *
+ *  In Ruby 1.9+, the returned strings will be encoded with the encoding
+ *  specified in the +Encoding+ header of the commit, if available.
+ *
+ */
+static VALUE rb_git_commit_trailers_GET(VALUE self)
+{
+	git_commit *commit;
+	const char *message;
+	rb_encoding *encoding = rb_utf8_encoding();
+	const char *encoding_name;
+	VALUE trailers = rb_ary_new();
+	int error;
+
+	Data_Get_Struct(self, git_commit, commit);
+
+	encoding_name = git_commit_message_encoding(commit);
+	if (encoding_name != NULL)
+		encoding = rb_enc_find(encoding_name);
+
+	struct trailer_cb_info cb_info = {
+		.trailers = trailers,
+		.encoding = encoding,
+	};
+
+	message = git_commit_message(commit);
+
+	error = git_message_trailers(message, rb_each_trailer, &cb_info);
+	rugged_exception_check(error);
+
+	return trailers;
+}
+
 /*
  *  call-seq:
  *    commit.summary -> summary
@@ -819,6 +883,7 @@ void Init_rugged_commit(void)
 	rb_define_singleton_method(rb_cRuggedCommit, "extract_signature", rb_git_commit_extract_signature, -1);
 
 	rb_define_method(rb_cRuggedCommit, "message", rb_git_commit_message_GET, 0);
+	rb_define_method(rb_cRuggedCommit, "trailers", rb_git_commit_trailers_GET, 0);
 	rb_define_method(rb_cRuggedCommit, "summary", rb_git_commit_summary_GET, 0);
 	rb_define_method(rb_cRuggedCommit, "epoch_time", rb_git_commit_epoch_time_GET, 0);
 	rb_define_method(rb_cRuggedCommit, "committer", rb_git_commit_committer_GET, 0);

test/commit_test.rb

@@ -699,4 +699,31 @@ def test_format_to_mbox_diff_options
 EOS
   end
 
+  class TrailersTest < Rugged::TestCase
+    def setup
+      @source_repo = FixtureRepo.from_rugged("testrepo.git")
+      @repo = FixtureRepo.clone(@source_repo)
+      @repo.config['core.abbrev'] = 7
+    end
+
+    def test_can_parse_trailers
+      person = {:name => 'Brian', :email => '[email protected]', :time => Time.now }
+
+      commit_oid = Rugged::Commit.create(@repo,
+        :message => "This is the commit message\n\nCo-authored-by: Charles <[email protected]>\nSigned-off-by: Arthur Schreiber <[email protected]>",
+        :committer => person,
+        :author => person,
+        :parents => [@repo.head.target],
+        :tree => @repo.head.target.tree_oid)
+
+      commit = @repo.lookup(commit_oid)
+
+      expected = [
+        ["Co-authored-by", "Charles <[email protected]>"],
+        ["Signed-off-by", "Arthur Schreiber <[email protected]>"]
+      ]
+
+      assert_equal expected, commit.trailers
+    end
+  end
 end