fix ordering of brainstormings on the landing page (#52)

lib/mindwendel/brainstormings.ex

@@ -10,6 +10,25 @@ defmodule Mindwendel.Brainstormings do
   alias Mindwendel.Brainstormings.Brainstorming
   alias Mindwendel.Brainstormings.Like
 
+  @doc """
+  Returns the 3 most recent brainstormings for a a user.
+
+  ## Examples
+
+      iex> list_brainstormings_for(3)
+      [%Brainstorming{}, ...]
+
+  """
+  def list_brainstormings_for(user_id) do
+    Repo.all(
+      from brainstorming in Brainstorming,
+        join: users in assoc(brainstorming, :users),
+        where: users.id == ^user_id,
+        order_by: [desc: brainstorming.inserted_at],
+        limit: 3
+    )
+  end
+
   @doc """
   Returns the list of ideas.
 

lib/mindwendel_web/templates/static_page/home.html.leex

@@ -29,15 +29,13 @@
       <div class="row mt-5">
         <div class="col-md-12 col-lg-12 mt-2">
           <h3>Your latest brainstormings</h3>
-          <%
-            sorted_brainstorming =
-              Enum.sort_by(@current_user.brainstormings, &(&1.inserted_at), {:desc, Time})
-                |> Enum.slice(0, 3)
-          %>
-          <%= for brainstorming <- sorted_brainstorming do %>
-            <a href="<%= Routes.brainstorming_show_path(@conn, :show, brainstorming) %>">
-              <h5><%= brainstorming.name %> <span class="badge rounded-pill bg-light text-dark"><%= Timex.format!(brainstorming.inserted_at, "{relative}", :relative) %></span></h5>
-            </a>
+          <%= for brainstorming <- list_brainstormings_for(@current_user) do %>
+          <h5>
+            <%= link brainstorming.name, to: Routes.brainstorming_show_path(@conn, :show, brainstorming) %>
+            <span class="badge rounded-pill bg-light text-dark">
+              <%= Timex.format!(brainstorming.inserted_at, "{relative}", :relative) %>
+            </span>
+          </h5>
           <% end %>
         </div>
       </div>

lib/mindwendel_web/views/static_page.ex

@@ -1,3 +1,8 @@
 defmodule MindwendelWeb.StaticPageView do
   use MindwendelWeb, :view
+  alias Mindwendel.Brainstormings
+
+  def list_brainstormings_for(user) do
+    Brainstormings.list_brainstormings_for(user.id)
+  end
 end

test/mindwendel/brainstormings_test.exs

@@ -4,17 +4,34 @@ defmodule Mindwendel.BrainstormingsTest do
   alias Mindwendel.Brainstormings
 
   setup do
-    brainstorming = Factory.insert!(:brainstorming)
+    user = Factory.insert!(:user)
+    brainstorming = Factory.insert!(:brainstorming, users: [user])
 
     %{
       brainstorming: brainstorming,
       idea:
         Factory.insert!(:idea, brainstorming: brainstorming, inserted_at: ~N[2021-01-01 15:04:30]),
-      user: Factory.insert!(:user),
+      user: user,
       like: Factory.insert!(:like, :with_idea_and_user)
     }
   end
 
+  describe "list_brainstormings_for" do
+    test "returns the 3 most recent brainstormings", %{brainstorming: brainstorming, user: user} do
+      older_brainstorming =
+        Factory.insert!(:brainstorming, inserted_at: ~N[2021-01-10 15:04:30], users: [user])
+
+      oldest_brainstorming =
+        Factory.insert!(:brainstorming, inserted_at: ~N[2021-01-05 15:04:30], users: [user])
+
+      assert Brainstormings.list_brainstormings_for(user.id) |> Enum.map(fn b -> b.id end) == [
+               brainstorming.id,
+               older_brainstorming.id,
+               oldest_brainstorming.id
+             ]
+    end
+  end
+
   describe "change brainstorming" do
     test "shortens the brainstorming name if it is too long", %{brainstorming: brainstorming} do
       result =

test/mindwendel_web/channels/brainstorming_channel_test.exs

@@ -3,7 +3,6 @@ defmodule MindwendelWeb.BrainstormingChannelTest do
 
   alias Mindwendel.Factory
   alias Mindwendel.Brainstormings
-  alias Mindwendel.Brainstormings.Idea
 
   setup do
     %{
@@ -17,7 +16,7 @@ defmodule MindwendelWeb.BrainstormingChannelTest do
 
       Brainstormings.subscribe(brainstorming.id)
       Brainstormings.update_idea(idea, %{body: "lalala"})
-      assert_received {:idea_updated, idea}
+      assert_received {:idea_updated, _}
     end
 
     test "does not receive messages from other brainstormings", %{brainstorming: brainstorming} do
@@ -26,7 +25,7 @@ defmodule MindwendelWeb.BrainstormingChannelTest do
 
       Brainstormings.subscribe(other_brainstorming.id)
       Brainstormings.update_idea(idea, %{body: "lalala"})
-      refute_received {:idea_updated, idea}
+      refute_received {:idea_updated, _}
     end
   end
 end