Share code for finding working tree in plumbing command modules. (#134)

lib/xgit/plumbing/ls_files/stage.ex

@@ -8,6 +8,7 @@ defmodule Xgit.Plumbing.LsFiles.Stage do
 
   alias Xgit.Core.DirCache
   alias Xgit.Core.DirCache.Entry, as: DirCacheEntry
+  alias Xgit.Plumbing.Util.WorkingTreeOpt
   alias Xgit.Repository
   alias Xgit.Repository.WorkingTree
   alias Xgit.Repository.WorkingTree.ParseIndexFile
@@ -42,16 +43,12 @@ defmodule Xgit.Plumbing.LsFiles.Stage do
           {:ok, entries :: [DirCacheEntry.t()]}
           | {:error, reason :: reason}
   def run(repository) when is_pid(repository) do
-    with {:repository_valid?, true} <- {:repository_valid?, Repository.valid?(repository)},
-         {:working_tree, working_tree} when is_pid(working_tree) <-
-           {:working_tree, Repository.default_working_tree(repository)},
-         {:dir_cache, {:ok, %DirCache{entries: entries} = _dir_cache}} <-
-           {:dir_cache, WorkingTree.dir_cache(working_tree)} do
+    with {:ok, working_tree} <- WorkingTreeOpt.get(repository),
+         {:ok, %DirCache{entries: entries} = _dir_cache} <-
+           WorkingTree.dir_cache(working_tree) do
       {:ok, entries}
     else
-      {:repository_valid?, false} -> {:error, :invalid_repository}
-      {:working_tree, nil} -> {:error, :bare}
-      {:dir_cache, {:error, reason}} -> {:error, reason}
+      {:error, reason} -> {:error, reason}
     end
   end
 end

lib/xgit/plumbing/update_index/cache_info.ex

@@ -10,6 +10,7 @@ defmodule Xgit.Plumbing.UpdateIndex.CacheInfo do
   alias Xgit.Core.DirCache.Entry, as: DirCacheEntry
   alias Xgit.Core.FilePath
   alias Xgit.Core.ObjectId
+  alias Xgit.Plumbing.Util.WorkingTreeOpt
   alias Xgit.Repository
   alias Xgit.Repository.WorkingTree
 
@@ -59,18 +60,14 @@ defmodule Xgit.Plumbing.UpdateIndex.CacheInfo do
           :ok | {:error, reason()}
   def run(repository, add, remove \\ [])
       when is_pid(repository) and is_list(add) and is_list(remove) do
-    with {:repository_valid?, true} <- {:repository_valid?, Repository.valid?(repository)},
+    with {:ok, working_tree} <- WorkingTreeOpt.get(repository),
          {:items_to_add, add} when is_list(add) <- {:items_to_add, parse_add_entries(add)},
          {:items_to_remove, remove} when is_list(remove) <-
-           {:items_to_remove, parse_remove_entries(remove)},
-         {:working_tree, working_tree} when is_pid(working_tree) <-
-           {:working_tree, Repository.default_working_tree(repository)} do
+           {:items_to_remove, parse_remove_entries(remove)} do
       WorkingTree.update_dir_cache(working_tree, add, remove)
     else
-      {:repository_valid?, false} -> {:error, :invalid_repository}
       {:items_to_add, _} -> {:error, :invalid_entry}
       {:items_to_remove, _} -> {:error, :invalid_entry}
-      {:working_tree, nil} -> {:error, :bare}
       {:error, reason} -> {:error, reason}
     end
   end

lib/xgit/plumbing/util/working_tree_opt.ex

@@ -0,0 +1,32 @@
+defmodule Xgit.Plumbing.Util.WorkingTreeOpt do
+  @moduledoc false
+  # For use by plumbing modules only.
+
+  alias Xgit.Repository
+  alias Xgit.Repository.WorkingTree
+
+  # Parse working tree and repository from arguments and options.
+
+  @spec get(repository :: Repository.t(), working_tree: WorkingTree.t()) ::
+          {:ok, WorkingTree.t()} | {:error, :invalid_repository | :bare}
+  def get(repository, opts \\ []) when is_pid(repository) and is_list(opts) do
+    with {:repository_valid?, true} <- {:repository_valid?, Repository.valid?(repository)},
+         {:working_tree, working_tree} when is_pid(working_tree) <-
+           {:working_tree, working_tree_from_repo_or_opts(repository, opts)} do
+      {:ok, working_tree}
+    else
+      {:repository_valid?, false} -> {:error, :invalid_repository}
+      {:working_tree, nil} -> {:error, :bare}
+    end
+  end
+
+  defp working_tree_from_repo_or_opts(repository, _opts) do
+    # TO DO: Allow working tree to be specified via options.
+    # https://github.com/elixir-git/xgit/issues/133
+    # (NOTE: Should follow through to ensure all relevant plumbing
+    # modules have that option documented when implemented.)
+    # For now, only recognize default working tree.
+
+    Repository.default_working_tree(repository)
+  end
+end