add Geef.Revwalk module for Elixir

test/revwalk_test.exs

@@ -0,0 +1,29 @@
+defmodule RevwalkTest do
+  use ExUnit.Case
+  use Geef
+  import RepoHelpers
+
+
+  setup do
+    {repo, path, head, boring_ancestor} = tmp_commit_line
+    Process.link(repo)
+    {:ok, walk} = Repository.revwalk(repo)
+    on_exit(fn -> File.rm_rf!(path) end)
+    {:ok, [walk: walk, head: head, boring_ancestor: boring_ancestor]}
+  end
+
+  test "walk and count", meta do
+    walk = meta[:walk]
+    Revwalk.push(walk, meta[:head])
+    Revwalk.hide(walk, meta[:boring_ancestor])
+    assert 3 = count_walk(walk)
+  end
+
+  defp count_walk walk, acc \\ 0
+  defp count_walk walk, acc do
+    case Revwalk.next(walk) do
+      {:ok, _} -> count_walk(walk, acc + 1)
+      {:error, :iterover} -> acc
+    end
+  end
+end