Expose utility ref-type functions

These allow you to determine whether you're dealing with a branch, tag,
note or remote-tracking branch.

src/geef_ref.erl

@@ -2,6 +2,7 @@
 
 -export([lookup/2, iterator/1, iterator/2, next/1, resolve/1, create/4, create_symbolic/4, dwim/2, shorthand/1]).
 -export([has_log/1, has_log/2]).
+-export([is_branch/1, is_tag/1, is_note/1, is_remote/1]).
 
 -include("geef_records.hrl").
 
@@ -113,3 +114,18 @@ has_log(Repo, Name) ->
 -spec has_log(ref()) -> {ok, boolean()} | {error, term()}.
 has_log(#geef_reference{repo=Repo, name=Name}) ->
     has_log(Repo, Name).
+
+-define(assert_prefix(FunctionName, Prefix),
+FunctionName(<<Prefix, _/binary>>) ->
+    true;
+FunctionName(#geef_reference{name=Name}) ->
+    FunctionName(Name);
+FunctionName(Name) when is_list(Name) ->
+    FunctionName(iolist_to_binary(Name));
+FunctionName(_) ->
+    false).
+
+?assert_prefix(is_branch, "refs/heads/").
+?assert_prefix(is_tag, "refs/tags/").
+?assert_prefix(is_note, "refs/notes/").
+?assert_prefix(is_remote, "refs/remotes/").

test/ref_test.erl

@@ -0,0 +1,39 @@
+-module(ref_test).
+-compile([export_all]).
+
+-include_lib("eunit/include/eunit.hrl").
+-include("src/geef_records.hrl").
+
+test_fun(F, [{Name, Val} | Tail]) ->
+    ?assertEqual(Val, F(Name)),
+    test_fun(F, Tail);
+test_fun(_, []) ->
+    ok.
+
+branch_test() ->
+    ?assertEqual(true, geef_ref:is_branch("refs/heads/master")),
+    ?assertEqual(true, geef_ref:is_branch(<<"refs/heads/master">>)),
+    ?assertEqual(false, geef_ref:is_branch("refs/tags/v0.1")),
+    ?assertEqual(false, geef_ref:is_branch(#geef_reference{name= <<"refs/tags/foo">>})),
+    ?assertEqual(true, geef_ref:is_branch(#geef_reference{name= <<"refs/heads/foo">>})).
+
+tag_test() ->
+    ?assertEqual(false, geef_ref:is_tag("refs/heads/master")),
+    ?assertEqual(true, geef_ref:is_tag(<<"refs/tags/mastery">>)),
+    ?assertEqual(true, geef_ref:is_tag("refs/tags/v0.1")),
+    ?assertEqual(true, geef_ref:is_tag(#geef_reference{name= <<"refs/tags/foo">>})),
+    ?assertEqual(false, geef_ref:is_tag(#geef_reference{name= <<"refs/heads/foo">>})).
+
+note_test() ->
+    ?assertEqual(false, geef_ref:is_note("refs/heads/master")),
+    ?assertEqual(true, geef_ref:is_note(<<"refs/notes/commits">>)),
+    ?assertEqual(true, geef_ref:is_note("refs/notes/bugs")),
+    ?assertEqual(true, geef_ref:is_note(#geef_reference{name= <<"refs/notes/foo">>})),
+    ?assertEqual(false, geef_ref:is_note(#geef_reference{name= <<"refs/heads/foo">>})).
+
+remote_test() ->
+    ?assertEqual(false, geef_ref:is_remote("refs/heads/master")),
+    ?assertEqual(true, geef_ref:is_remote(<<"refs/remotes/origin/master">>)),
+    ?assertEqual(true, geef_ref:is_remote("refs/remotes/origin/development")),
+    ?assertEqual(true, geef_ref:is_remote(#geef_reference{name= <<"refs/remotes/svn">>})),
+    ?assertEqual(false, geef_ref:is_remote(#geef_reference{name= <<"refs/heads/foo">>})).