fix(config): adopt default values when user-provided value is nil

lib/beacon/config.ex

@@ -425,15 +425,15 @@ defmodule Beacon.Config do
     opts[:router] || raise ConfigError, "missing required option :router"
     ensure_repo(opts[:repo])
 
-    tailwind_css = Keyword.get(opts, :tailwind_css) || Path.join(Application.app_dir(:beacon, "priv"), "tailwind.css")
+    tailwind_css = get_opt(opts, :tailwind_css, Path.join(Application.app_dir(:beacon, "priv"), "tailwind.css"))
 
     template_formats =
       Keyword.merge(
         [
           {:heex, "HEEx (HTML)"},
           {:markdown, "Markdown (GitHub Flavored version)"}
         ],
-        Keyword.get(opts, :template_formats, [])
+        get_opt(opts, :template_formats, [])
       )
 
     lifecycle = [
@@ -445,32 +445,36 @@ defmodule Beacon.Config do
       upload_asset: get_in(opts, [:lifecycle, :upload_asset]) || [thumbnail: &Beacon.Lifecycle.Asset.thumbnail/2]
     ]
 
-    allowed_media_accept_types = Keyword.get(opts, :allowed_media_accept_types, @default_media_types)
+    allowed_media_accept_types = get_opt(opts, :allowed_media_accept_types, @default_media_types)
     validate_allowed_media_accept_types!(allowed_media_accept_types)
 
-    assigned_assets = Keyword.get(opts, :assets, [])
+    assigned_assets = get_opt(opts, :assets, [])
     assets = process_assets_config(allowed_media_accept_types, assigned_assets)
 
-    default_meta_tags = Keyword.get(opts, :default_meta_tags, [])
-    extra_asset_fields = Keyword.get(opts, :extra_asset_fields, [{"image/*", [Beacon.MediaLibrary.AssetFields.AltText]}])
-
-    page_warming = Keyword.get(opts, :page_warming, {:shortest_paths, 10})
-
-    opts =
-      opts
-      |> Keyword.put(:tailwind_config, ensure_tailwind_config(opts[:tailwind_config]))
-      |> Keyword.put(:tailwind_css, tailwind_css)
-      |> Keyword.put(:template_formats, template_formats)
-      |> Keyword.put(:lifecycle, lifecycle)
-      |> Keyword.put(:allowed_media_accept_types, allowed_media_accept_types)
-      |> Keyword.put(:assets, assets)
-      |> Keyword.put(:default_meta_tags, default_meta_tags)
-      |> Keyword.put(:extra_asset_fields, extra_asset_fields)
-      |> Keyword.put(:page_warming, page_warming)
-
-    struct!(__MODULE__, opts)
+    default_meta_tags = get_opt(opts, :default_meta_tags, [])
+    extra_asset_fields = get_opt(opts, :extra_asset_fields, [{"image/*", [Beacon.MediaLibrary.AssetFields.AltText]}])
+
+    page_warming = get_opt(opts, :page_warming, {:shortest_paths, 10})
+
+    struct!(
+      __MODULE__,
+      Keyword.merge(opts,
+        tailwind_config: ensure_tailwind_config(opts[:tailwind_config]),
+        tailwind_css: tailwind_css,
+        template_formats: template_formats,
+        lifecycle: lifecycle,
+        allowed_media_accept_types: allowed_media_accept_types,
+        assets: assets,
+        default_meta_tags: default_meta_tags,
+        extra_asset_fields: extra_asset_fields,
+        page_warming: page_warming
+      )
+    )
   end
 
+  # Get `key` from `opts` keyword, otherwise returns `default` even if the key is present but returns `nil`.
+  defp get_opt(opts, key, default), do: Keyword.get(opts, key) || default
+
   @doc """
   Returns the `Beacon.Config` for `site`.
   """

test/beacon/config_test.exs

@@ -1,11 +1,24 @@
 defmodule Beacon.ConfigTest do
   use ExUnit.Case, async: true
 
-  alias Beacon.Config
-
   @site :my_site
   @repo Beacon.BeaconTest.Repo
 
+  test "returns default when value is nil" do
+    assert %Beacon.Config{
+             default_meta_tags: [],
+             page_warming: {:shortest_paths, 10}
+           } =
+             Beacon.Config.new(
+               site: :site,
+               endpoint: :endpoint,
+               router: :router,
+               repo: @repo,
+               default_meta_tags: nil,
+               page_warming: nil
+             )
+  end
+
   describe "registry" do
     test "returns the site config" do
       assert %Beacon.Config{
@@ -14,19 +27,19 @@ defmodule Beacon.ConfigTest do
                safe_code_check: false,
                site: :my_site,
                tailwind_config: tailwind_config
-             } = Config.fetch!(@site)
+             } = Beacon.Config.fetch!(@site)
 
       assert tailwind_config =~ "tailwind.config.templates.js"
     end
 
     test "raises for non existing site" do
       assert_raise Beacon.ConfigError, ~r/site :invalid not found/, fn ->
-        Config.fetch!(:invalid)
+        Beacon.Config.fetch!(:invalid)
       end
     end
 
     test "updates key from config" do
-      assert %Config{live_socket_path: "/new_live"} = Config.update_value(:not_booted, :live_socket_path, "/new_live")
+      assert %Beacon.Config{live_socket_path: "/new_live"} = Beacon.Config.update_value(:not_booted, :live_socket_path, "/new_live")
     end
   end
 
@@ -37,7 +50,7 @@ defmodule Beacon.ConfigTest do
                  {:heex, "HEEx (HTML)"},
                  {:markdown, "Markdown (GitHub Flavored version)"}
                ]
-             } = Config.new(site: :site, endpoint: :endpoint, router: :router, repo: @repo, template_formats: [])
+             } = Beacon.Config.new(site: :site, endpoint: :endpoint, router: :router, repo: @repo, template_formats: [])
     end
 
     test "merge existing config" do
@@ -46,7 +59,14 @@ defmodule Beacon.ConfigTest do
                  {:markdown, "Markdown (GitHub Flavored version)"},
                  {:heex, "Custom HEEx description"}
                ]
-             } = Config.new(site: :site, endpoint: :endpoint, router: :router, repo: @repo, template_formats: [{:heex, "Custom HEEx description"}])
+             } =
+               Beacon.Config.new(
+                 site: :site,
+                 endpoint: :endpoint,
+                 router: :router,
+                 repo: @repo,
+                 template_formats: [{:heex, "Custom HEEx description"}]
+               )
     end
 
     test "add config" do
@@ -56,7 +76,14 @@ defmodule Beacon.ConfigTest do
                  {:markdown, "Markdown (GitHub Flavored version)"},
                  {:custom_format, "Custom Format"}
                ]
-             } = Config.new(site: :site, endpoint: :endpoint, router: :router, repo: @repo, template_formats: [{:custom_format, "Custom Format"}])
+             } =
+               Beacon.Config.new(
+                 site: :site,
+                 endpoint: :endpoint,
+                 router: :router,
+                 repo: @repo,
+                 template_formats: [{:custom_format, "Custom Format"}]
+               )
     end
   end
 
@@ -71,7 +98,7 @@ defmodule Beacon.ConfigTest do
                  after_publish_page: [],
                  upload_asset: [{:thumbnail, _}]
                ]
-             } = Config.new(site: :site, endpoint: :endpoint, router: :router, repo: @repo, lifecycle: [load_template: []])
+             } = Beacon.Config.new(site: :site, endpoint: :endpoint, router: :router, repo: @repo, lifecycle: [load_template: []])
     end
   end
 
@@ -108,20 +135,20 @@ defmodule Beacon.ConfigTest do
                   {:validations, []},
                   {:providers, [Beacon.MediaLibrary.Provider.Repo]}
                 ]}
-             ] = Config.new(site: :site, endpoint: :endpoint, router: :router, repo: @repo).assets
+             ] = Beacon.Config.new(site: :site, endpoint: :endpoint, router: :router, repo: @repo).assets
     end
   end
 
   describe "config_for_media_type/2" do
     test "retrieves" do
       media_type = "image/jpeg"
-      config = Config.new(site: :site, endpoint: :endpoint, router: :router, repo: @repo)
+      config = Beacon.Config.new(site: :site, endpoint: :endpoint, router: :router, repo: @repo)
 
       assert [
                {:processor, _},
                {:validations, []},
                {:providers, [Beacon.MediaLibrary.Provider.Repo]}
-             ] = Config.config_for_media_type(config, media_type)
+             ] = Beacon.Config.config_for_media_type(config, media_type)
     end
   end
 end