lib/mv_web/live/contribution_period_live/show.ex

@@ -36,7 +36,7 @@ defmodule MvWeb.ContributionPeriodLive.Show do
       <.mockup_warning />
 
       <.header>
-        {gettext("Contributions for %{name}", name: "#{@member.first_name} #{@member.last_name}")}
+        {gettext("Contributions for %{name}", name: MvWeb.MemberLive.Index.display_name(@member))}
         <:subtitle>
           {gettext("Contribution type")}:
           <span class="font-semibold">{@member.contribution_type}</span>

lib/mv_web/live/custom_field_value_live/form.ex

@@ -289,6 +289,6 @@ defmodule MvWeb.CustomFieldValueLive.Form do
   end
 
   defp member_options(members) do
-    Enum.map(members, &{"#{&1.first_name} #{&1.last_name}", &1.id})
+    Enum.map(members, &{MvWeb.MemberLive.Index.display_name(&1), &1.id})
   end
 end

lib/mv_web/live/member_live/form.ex

@@ -43,7 +43,7 @@ defmodule MvWeb.MemberLive.Form do
 
           <h1 class="text-2xl font-bold text-center flex-1">
             <%= if @member do %>
-              {@member.first_name} {@member.last_name}
+              {MvWeb.MemberLive.Index.display_name(@member)}
             <% else %>
               {gettext("New Member")}
             <% end %>

lib/mv_web/live/member_live/index.ex

@@ -1165,6 +1165,62 @@ defmodule MvWeb.MemberLive.Index do
     end
   end
 
+  @doc """
+  Returns a display name for a member.
+
+  Combines first_name and last_name if available, otherwise falls back to email.
+  This ensures that members without names still have a meaningful display name.
+
+  ## Examples
+
+      iex> member = %Member{first_name: "John", last_name: "Doe", email: "john@example.com"}
+      iex> display_name(member)
+      "John Doe"
+
+      iex> member = %Member{first_name: nil, last_name: nil, email: "john@example.com"}
+      iex> display_name(member)
+      "john@example.com"
+
+      iex> member = %Member{first_name: "John", last_name: nil, email: "john@example.com"}
+      iex> display_name(member)
+      "John"
+  """
+  def display_name(member) do
+    name_parts =
+      [member.first_name, member.last_name]
+      |> Enum.reject(&blank?/1)
+      |> Enum.map(&String.trim/1)
+      |> Enum.join(" ")
+
+    if name_parts == "" do
+      member.email
+    else
+      name_parts
+    end
+  end
+
+  @doc """
+  Checks if a value is blank (nil, empty string, or only whitespace).
+
+  ## Examples
+
+      iex> blank?(nil)
+      true
+
+      iex> blank?("")
+      true
+
+      iex> blank?("   ")
+      true
+
+      iex> blank?("John")
+      false
+  """
+  def blank?(nil), do: true
+  def blank?(""), do: true
+  def blank?(value) when is_binary(value), do: String.trim(value) == ""
+  def blank?(_), do: false
+
   # Public helper function to format dates for use in templates
   def format_date(date), do: DateFormatter.format_date(date)
 

lib/mv_web/live/member_live/index.html.heex

@@ -129,7 +129,12 @@
         """
       }
     >
-      {member.first_name}
+      {if MvWeb.MemberLive.Index.blank?(member.first_name) &&
+            MvWeb.MemberLive.Index.blank?(member.last_name) do
+        MvWeb.MemberLive.Index.display_name(member)
+      else
+        member.first_name
+      end}
     </:col>
     <:col
       :let={member}

lib/mv_web/live/member_live/show.ex

@@ -35,7 +35,7 @@ defmodule MvWeb.MemberLive.Show do
         </.button>
 
         <h1 class="text-2xl font-bold text-center flex-1">
-          {@member.first_name} {@member.last_name}
+          {MvWeb.MemberLive.Index.display_name(@member)}
         </h1>
 
         <.button variant="primary" navigate={~p"/members/#{@member}/edit?return_to=show"}>

lib/mv_web/live/user_live/form.ex

@@ -131,7 +131,7 @@ defmodule MvWeb.UserLive.Form do
               <div class="flex items-center justify-between">
                 <div>
                   <p class="font-medium text-green-900">
-                    {@user.member.first_name} {@user.member.last_name}
+                    {MvWeb.MemberLive.Index.display_name(@user.member)}
                   </p>
                   <p class="text-sm text-green-700">{@user.member.email}</p>
                 </div>
@@ -210,7 +210,7 @@ defmodule MvWeb.UserLive.Form do
                           )
                         ]}
                       >
-                        <p class="font-medium">{member.first_name} {member.last_name}</p>
+                        <p class="font-medium">{MvWeb.MemberLive.Index.display_name(member)}</p>
                         <p class="text-sm text-base-content/70">{member.email}</p>
                       </div>
                     <% end %>
@@ -438,7 +438,7 @@ defmodule MvWeb.UserLive.Form do
 
     member_name =
       if selected_member,
-        do: "#{selected_member.first_name} #{selected_member.last_name}",
+        do: MvWeb.MemberLive.Index.display_name(selected_member),
         else: ""
 
     # Store the selected member ID and name in socket state and clear unlink flag

lib/mv_web/live/user_live/index.html.heex

@@ -51,7 +51,7 @@
     </:col>
     <:col :let={user} label={gettext("Linked Member")}>
       <%= if user.member do %>
-        {user.member.first_name} {user.member.last_name}
+        {MvWeb.MemberLive.Index.display_name(user.member)}
       <% else %>
         <span class="text-base-content/50">{gettext("No member linked")}</span>
       <% end %>

lib/mv_web/live/user_live/show.ex

@@ -57,7 +57,7 @@ defmodule MvWeb.UserLive.Show do
               class="text-blue-600 underline hover:text-blue-800"
             >
               <.icon name="hero-users" class="inline w-4 h-4 mr-1" />
-              {@user.member.first_name} {@user.member.last_name}
+              {MvWeb.MemberLive.Index.display_name(@user.member)}
             </.link>
           <% else %>
             <span class="italic text-gray-500">{gettext("No member linked")}</span>

test/mv_web/member_live/index_display_name_test.exs

@@ -0,0 +1,141 @@
+defmodule MvWeb.MemberLive.Index.DisplayNameTest do
+  @moduledoc """
+  Tests for the display_name/1 helper function in MemberLive.Index.
+  """
+  use Mv.DataCase, async: true
+
+  alias Mv.Membership.Member
+  alias MvWeb.MemberLive.Index
+
+  describe "display_name/1" do
+    test "returns full name when both first_name and last_name are present" do
+      member = %Member{
+        first_name: "John",
+        last_name: "Doe",
+        email: "john@example.com"
+      }
+
+      assert Index.display_name(member) == "John Doe"
+    end
+
+    test "returns email when both first_name and last_name are nil" do
+      member = %Member{
+        first_name: nil,
+        last_name: nil,
+        email: "john@example.com"
+      }
+
+      assert Index.display_name(member) == "john@example.com"
+    end
+
+    test "returns first_name only when last_name is nil" do
+      member = %Member{
+        first_name: "John",
+        last_name: nil,
+        email: "john@example.com"
+      }
+
+      assert Index.display_name(member) == "John"
+    end
+
+    test "returns last_name only when first_name is nil" do
+      member = %Member{
+        first_name: nil,
+        last_name: "Doe",
+        email: "john@example.com"
+      }
+
+      assert Index.display_name(member) == "Doe"
+    end
+
+    test "returns email when first_name and last_name are empty strings" do
+      member = %Member{
+        first_name: "",
+        last_name: "",
+        email: "john@example.com"
+      }
+
+      assert Index.display_name(member) == "john@example.com"
+    end
+
+    test "returns email when first_name and last_name are whitespace only" do
+      member = %Member{
+        first_name: "   ",
+        last_name: "  \t  ",
+        email: "john@example.com"
+      }
+
+      assert Index.display_name(member) == "john@example.com"
+    end
+
+    test "trims whitespace from name parts" do
+      member = %Member{
+        first_name: "  John  ",
+        last_name: "  Doe  ",
+        email: "john@example.com"
+      }
+
+      assert Index.display_name(member) == "John Doe"
+    end
+
+    test "handles one empty string and one nil" do
+      member = %Member{
+        first_name: "",
+        last_name: nil,
+        email: "john@example.com"
+      }
+
+      assert Index.display_name(member) == "john@example.com"
+    end
+
+    test "handles one nil and one empty string" do
+      member = %Member{
+        first_name: nil,
+        last_name: "",
+        email: "john@example.com"
+      }
+
+      assert Index.display_name(member) == "john@example.com"
+    end
+
+    test "handles one whitespace and one nil" do
+      member = %Member{
+        first_name: "   ",
+        last_name: nil,
+        email: "john@example.com"
+      }
+
+      assert Index.display_name(member) == "john@example.com"
+    end
+
+    test "handles one valid name and one whitespace" do
+      member = %Member{
+        first_name: "John",
+        last_name: "   ",
+        email: "john@example.com"
+      }
+
+      assert Index.display_name(member) == "John"
+    end
+
+    test "handles member with only first_name containing whitespace" do
+      member = %Member{
+        first_name: "  John  ",
+        last_name: nil,
+        email: "john@example.com"
+      }
+
+      assert Index.display_name(member) == "John"
+    end
+
+    test "handles member with only last_name containing whitespace" do
+      member = %Member{
+        first_name: nil,
+        last_name: "  Doe  ",
+        email: "john@example.com"
+      }
+
+      assert Index.display_name(member) == "Doe"
+    end
+  end
+end