fix: allow atom layout module names

lib/tableau/extensions/page_extension.ex

@@ -73,7 +73,7 @@ defmodule Tableau.PageExtension do
         optional(:enabled, true) => bool(),
         optional(:dir, "_pages") => str(),
         optional(:permalink) => str(),
-        optional(:layout) => str()
+        optional(:layout) => oneof([str(), atom()])
       }),
       input
     )
@@ -113,7 +113,7 @@ defmodule Tableau.PageExtension do
     |> Map.put(:__tableau_page_extension__, true)
     |> Map.put(:body, body)
     |> Map.put(:file, filename)
-    |> Map.put(:layout, Module.concat([front_matter.layout || pages_config.layout]))
+    |> Map.put(:layout, Module.concat([front_matter[:layout] || pages_config.layout]))
     |> Common.build_permalink(pages_config)
   end
 end

lib/tableau/extensions/post_extension.ex

@@ -81,7 +81,7 @@ defmodule Tableau.PostExtension do
         optional(:dir, "_posts") => str(),
         optional(:future, false) => bool(),
         optional(:permalink) => str(),
-        optional(:layout) => str()
+        optional(:layout) => oneof([atom(), str()])
       }),
       config
     )

test/tableau/extensions/page_extension_test.exs

@@ -13,7 +13,7 @@ defmodule Tableau.PageExtensionTest do
 
   describe "run" do
     setup %{tmp_dir: dir} do
-      assert {:ok, config} = PageExtension.config(%{dir: dir, enabled: true})
+      assert {:ok, config} = PageExtension.config(%{dir: dir, enabled: true, layout: Blog.DefaultPageLayout})
 
       token = %{
         site: %{config: %{converters: [md: Tableau.MDExConverter]}},
@@ -200,5 +200,33 @@ defmodule Tableau.PageExtensionTest do
                ]
              } = token
     end
+
+    test "inherits layout from page extension config", %{tmp_dir: dir, token: token} do
+      File.write(Path.join(dir, "a-page.md"), """
+      ---
+      title: missing layout key
+      type: articles
+      permalink: /:type/:title
+      ---
+
+      A great page
+      """)
+
+      assert {:ok, token} = PageExtension.run(token)
+
+      assert %{
+               pages: [
+                 %{
+                   __tableau_page_extension__: true,
+                   body: "\nA great page\n",
+                   file: ^dir <> "/a-page.md",
+                   layout: Blog.DefaultPageLayout,
+                   permalink: "/articles/missing-layout-key",
+                   title: "missing layout key",
+                   type: "articles"
+                 }
+               ]
+             } = token
+    end
   end
 end

test/tableau/extensions/post_extension_test.exs

@@ -13,7 +13,7 @@ defmodule Tableau.PostExtensionTest do
 
   describe "run" do
     setup %{tmp_dir: dir} do
-      assert {:ok, config} = PostExtension.config(%{dir: dir, enabled: true})
+      assert {:ok, config} = PostExtension.config(%{dir: dir, enabled: true, layout: Blog.DefaultPostLayout})
 
       token = %{
         site: %{config: %{converters: [md: Tableau.MDExConverter]}},
@@ -233,6 +233,34 @@ defmodule Tableau.PostExtensionTest do
              } = token
     end
 
+    test "inherits layout from post extension config", %{tmp_dir: dir, token: token} do
+      File.write(Path.join(dir, "a-post.md"), """
+      ---
+      title: Missing layout key
+      date: 2018-02-28
+      permalink: /:title
+      ---
+
+      A great post
+      """)
+
+      assert {:ok, token} = PostExtension.run(token)
+
+      assert %{
+               posts: [
+                 %{
+                   __tableau_post_extension__: true,
+                   body: "\nA great post\n",
+                   date: ~U[2018-02-28 00:00:00Z],
+                   file: ^dir <> "/a-post.md",
+                   layout: Blog.DefaultPostLayout,
+                   permalink: "/missing-layout-key",
+                   title: "Missing layout key"
+                 }
+               ]
+             } = token
+    end
+
     test "handles frontmatter data in the permalink", %{tmp_dir: dir, token: token} do
       File.write(Path.join(dir, "a-post.md"), """
       ---