diff --git a/installer/lib/phx_new/generator.ex b/installer/lib/phx_new/generator.ex
index 282de5c429..99710dc2d2 100644
--- a/installer/lib/phx_new/generator.ex
+++ b/installer/lib/phx_new/generator.ex
@@ -128,7 +128,7 @@ defmodule Phx.New.Generator do
           project.binding[:javascript] && project.binding[:css] &&
             @new_project_rules_files["assets.md"],
           # generic usage rules
-          "\n<!-- usage-rules-start -->",
+          "<!-- usage-rules-start -->",
           [
             "<!-- phoenix:elixir-start -->\n",
             @rules_files["elixir.md"],
@@ -157,7 +157,7 @@ defmodule Phx.New.Generator do
               @rules_files["liveview.md"],
               "\n<!-- phoenix:liveview-end -->"
             ],
-          "<!-- usage-rules-end -->"
+          "<!-- usage-rules-end -->\n"
         ]
         |> Enum.reject(fn part -> part == nil or part == false end)
         |> Enum.intersperse("\n\n")
diff --git a/installer/templates/phx_assets/app.js.eex b/installer/templates/phx_assets/app.js.eex
index f22e06639f..5992c28515 100644
--- a/installer/templates/phx_assets/app.js.eex
+++ b/installer/templates/phx_assets/app.js.eex
@@ -15,8 +15,8 @@
 //     import "some-package"
 //
 // If you have dependencies that try to import CSS, esbuild will generate a separate `app.css` file.
-// To load it, simply add a second `<link>` to your `root.html.heex` file.
-<%= if @html do %>
+// To load it, simply add a second `<link>` to your `root.html.heex` file.<%= if @html do %>
+
 // Include phoenix_html to handle method=PUT/DELETE in forms and buttons.
 import "phoenix_html"
 // Establish Phoenix Socket and LiveView configuration.
@@ -79,12 +79,11 @@ import "phoenix_html"
 <%= @live_comment %>
 <%= @live_comment %>    window.liveReloader = reloader
 <%= @live_comment %>  })
-<%= @live_comment %>}
+<%= @live_comment %>}<%= if not @live do %>
 
-<%= if not @live do %>
 // Handle flash close
 document.querySelectorAll("[role=alert][data-flash]").forEach((el) => {
   el.addEventListener("click", () => {
     el.setAttribute("hidden", "")
   })
-})<% end %><% end %>
\ No newline at end of file
+})<% end %><% end %>
diff --git a/installer/templates/phx_gettext/errors.pot.eex b/installer/templates/phx_gettext/errors.pot.eex
index 577244ef36..f820c2a5ec 100644
--- a/installer/templates/phx_gettext/errors.pot.eex
+++ b/installer/templates/phx_gettext/errors.pot.eex
@@ -6,8 +6,8 @@
 ##
 ## Run `mix gettext.extract` to bring this file up to
 ## date. Leave `msgstr`s empty as changing them here has no
-## effect: edit them in PO (`.po`) files instead.
-<%= if @ecto do %>## From Ecto.Changeset.cast/4
+## effect: edit them in PO (`.po`) files instead.<%= if @ecto do %>
+## From Ecto.Changeset.cast/4
 msgid "can't be blank"
 msgstr ""
 
diff --git a/installer/templates/phx_single/gitignore.eex b/installer/templates/phx_single/gitignore.eex
index b32013e3a5..4d7f1c95f6 100644
--- a/installer/templates/phx_single/gitignore.eex
+++ b/installer/templates/phx_single/gitignore.eex
@@ -23,8 +23,8 @@ erl_crash.dump
 /tmp/
 
 # Ignore package tarball (built via "mix hex.build").
-<%= @app_name %>-*.tar
-<%= if @javascript or @css do %>
+<%= @app_name %>-*.tar<%= if @javascript or @css do %>
+
 # Ignore assets that are produced by build tools.
 /priv/static/assets/
 
@@ -33,9 +33,8 @@ erl_crash.dump
 
 # In case you use Node.js/npm, you want to ignore these.
 npm-debug.log
-/assets/node_modules/
-<% end %><%= if @adapter_app == :ecto_sqlite3 do %>
+/assets/node_modules/<% end %><%= if @adapter_app == :ecto_sqlite3 do %>
+
 # Database files
 *.db
-*.db-*
-<% end %>
+*.db-*<% end %>
diff --git a/installer/templates/phx_static/default.css b/installer/templates/phx_static/default.css
index 40e1e8b932..3403a21a14 100644
--- a/installer/templates/phx_static/default.css
+++ b/installer/templates/phx_static/default.css
@@ -2587,4 +2587,3 @@
     transform: rotate(360deg);
   }
 }
-
diff --git a/installer/templates/phx_umbrella/apps/app_name_web/gitignore.eex b/installer/templates/phx_umbrella/apps/app_name_web/gitignore.eex
index 4f23a32d90..d6c802adf3 100644
--- a/installer/templates/phx_umbrella/apps/app_name_web/gitignore.eex
+++ b/installer/templates/phx_umbrella/apps/app_name_web/gitignore.eex
@@ -23,8 +23,8 @@ erl_crash.dump
 /tmp/
 
 # Ignore package tarball (built via "mix hex.build").
-<%= @web_app_name %>-*.tar
-<%= if @javascript or @css do %>
+<%= @web_app_name %>-*.tar<%= if @javascript or @css do %>
+
 # Ignore assets that are produced by build tools.
 /priv/static/assets/
 
@@ -33,9 +33,8 @@ erl_crash.dump
 
 # In case you use Node.js/npm, you want to ignore these.
 npm-debug.log
-/assets/node_modules/
-<% end %><%= if @adapter_app == :ecto_sqlite3 do %>
+/assets/node_modules/<% end %><%= if @adapter_app == :ecto_sqlite3 do %>
+
 # Database files
 *.db
-*.db-*
-<% end %>
+*.db-*<% end %>
diff --git a/installer/templates/phx_umbrella/config/test.exs.eex b/installer/templates/phx_umbrella/config/test.exs.eex
index a5ed60f0c8..9e99acc783 100644
--- a/installer/templates/phx_umbrella/config/test.exs.eex
+++ b/installer/templates/phx_umbrella/config/test.exs.eex
@@ -16,7 +16,7 @@ config :phoenix, :plug_init_mode, :runtime<%= if @html do %>
 # Enable helpful, but potentially expensive runtime checks
 config :phoenix_live_view,
   enable_expensive_runtime_checks: true<% end %>
-  
+
 # Sort query params output of verified routes for robust url comparisons
 config :phoenix,
-  sort_verified_routes_query_params: true
\ No newline at end of file
+  sort_verified_routes_query_params: true
diff --git a/installer/templates/phx_umbrella/gitignore.eex b/installer/templates/phx_umbrella/gitignore.eex
index 59679f6efb..c403299c06 100644
--- a/installer/templates/phx_umbrella/gitignore.eex
+++ b/installer/templates/phx_umbrella/gitignore.eex
@@ -20,10 +20,8 @@ erl_crash.dump
 *.ez
 
 # Temporary files, for example, from tests.
-/tmp/
+/tmp/<%= if @adapter_app == :ecto_sqlite3 do %>
 
-<%= if @adapter_app == :ecto_sqlite3 do %>
 # Database files
 *.db
-*.db-*
-<% end %>
+*.db-*<% end %>
diff --git a/installer/test/mix_helper.exs b/installer/test/mix_helper.exs
index f11a094085..be5b4b5064 100644
--- a/installer/test/mix_helper.exs
+++ b/installer/test/mix_helper.exs
@@ -96,8 +96,21 @@ defmodule MixHelper do
 
   def assert_file(file) do
     assert File.regular?(file), "Expected #{file} to exist, but does not"
+    content = File.read!(file)
+
+    if not binary_file?(file) do
+      # \S\n\z matches non-whitespace followed by a single newline at EOF
+      assert content == "" or content =~ ~r/\S\n\z/,
+             "Expected #{file} to end with a single trailing newline"
+
+      refute content =~ "\n\n\n", "Expected #{file} to not contain consecutive blank lines"
+    end
+
+    content
   end
 
+  defp binary_file?(file), do: Path.extname(file) in ~w(.ico .pem .png)
+
   def refute_file(file) do
     refute File.regular?(file), "Expected #{file} to not exist, but it does"
   end
@@ -111,8 +124,8 @@ defmodule MixHelper do
         assert_file(file, &assert(&1 =~ match))
 
       is_function(match, 1) ->
-        assert_file(file)
-        match.(File.read!(file))
+        content = assert_file(file)
+        match.(content)
 
       true ->
         raise inspect({file, match})
diff --git a/installer/test/phx_new_test.exs b/installer/test/phx_new_test.exs
index 489dca741d..a347f2f771 100644
--- a/installer/test/phx_new_test.exs
+++ b/installer/test/phx_new_test.exs
@@ -147,7 +147,6 @@ defmodule Mix.Tasks.Phx.NewTest do
       assert_file("phx_blog/.gitignore", fn file ->
         assert file =~ "/priv/static/assets/"
         assert file =~ "phx_blog-*.tar"
-        assert file =~ ~r/\n$/
       end)
 
       assert_file("phx_blog/config/dev.exs", fn file ->
@@ -324,7 +323,6 @@ defmodule Mix.Tasks.Phx.NewTest do
       # No assets
       assert_file("phx_blog/.gitignore", fn file ->
         refute file =~ "/priv/static/assets/"
-        assert file =~ ~r/\n$/
       end)
 
       refute File.exists?("phx_blog/priv/static/images/logo.svg")
@@ -531,8 +529,6 @@ defmodule Mix.Tasks.Phx.NewTest do
         refute file =~ "/priv/static/assets/"
       end)
 
-      assert_file("phx_blog/.gitignore")
-      assert_file("phx_blog/.gitignore", ~r/\n$/)
       assert_file("phx_blog/priv/static/assets/css/app.css")
       assert_file("phx_blog/priv/static/assets/js/app.js")
       assert_file("phx_blog/priv/static/favicon.ico")
@@ -592,7 +588,6 @@ defmodule Mix.Tasks.Phx.NewTest do
       Mix.Tasks.Phx.New.run([project_path, "--app", @app_name, "--module", "PhoteuxBlog"])
 
       assert_file("custom_path/.gitignore")
-      assert_file("custom_path/.gitignore", ~r/\n$/)
       assert_file("custom_path/mix.exs", ~r/app: :phx_blog/)
       assert_file("custom_path/lib/phx_blog_web/endpoint.ex", ~r/app: :phx_blog/)
       assert_file("custom_path/config/config.exs", ~r/namespace: PhoteuxBlog/)
diff --git a/installer/test/phx_new_umbrella_test.exs b/installer/test/phx_new_umbrella_test.exs
index 5625e569b3..38d956ec5f 100644
--- a/installer/test/phx_new_umbrella_test.exs
+++ b/installer/test/phx_new_umbrella_test.exs
@@ -194,9 +194,10 @@ defmodule Mix.Tasks.Phx.New.UmbrellaTest do
       end)
 
       # assets
-      assert_file(web_path(@app, ".gitignore"), "/priv/static/assets/")
-      assert_file(web_path(@app, ".gitignore"), "#{@app}_web-*.tar")
-      assert_file(web_path(@app, ".gitignore"), ~r/\n$/)
+      assert_file(web_path(@app, ".gitignore"), fn file ->
+        assert file =~ "/priv/static/assets/"
+        assert file =~ "#{@app}_web-*.tar"
+      end)
 
       assert_file(web_path(@app, "assets/css/app.css"), fn file ->
         assert file =~ "lib/phx_umb_web"
@@ -353,7 +354,6 @@ defmodule Mix.Tasks.Phx.New.UmbrellaTest do
 
       # No assets
       assert_file(web_path(@app, ".gitignore"), fn file ->
-        assert file =~ ~r/\n$/
         refute file =~ "/priv/static/assets/"
       end)
 
@@ -516,8 +516,10 @@ defmodule Mix.Tasks.Phx.New.UmbrellaTest do
     in_tmp("new with no_assets", fn ->
       Mix.Tasks.Phx.New.run([@app, "--umbrella", "--no-assets"])
 
-      refute File.read!(web_path(@app, ".gitignore")) |> String.contains?("/priv/static/assets/")
-      assert_file(web_path(@app, ".gitignore"), ~r/\n$/)
+      assert_file(web_path(@app, ".gitignore"), fn file ->
+        refute file =~ "/priv/static/assets/"
+      end)
+
       assert_file(web_path(@app, "priv/static/assets/js/app.js"))
       assert_file(web_path(@app, "priv/static/assets/css/app.css"))
       assert_file(web_path(@app, "priv/static/favicon.ico"))
@@ -883,7 +885,7 @@ defmodule Mix.Tasks.Phx.New.UmbrellaTest do
         assert_file("another/lib/another/components/layouts/root.html.heex")
 
         # assets
-        assert_file("another/.gitignore", ~r/\n$/)
+        assert_file("another/.gitignore")
         assert_file("another/priv/static/favicon.ico")
         assert_file("another/assets/css/app.css")
 
diff --git a/lib/mix/phoenix/schema.ex b/lib/mix/phoenix/schema.ex
index 359133461f..47176e001d 100644
--- a/lib/mix/phoenix/schema.ex
+++ b/lib/mix/phoenix/schema.ex
@@ -262,6 +262,45 @@ defmodule Mix.Phoenix.Schema do
     end)
   end
 
+  def format_schema_body(schema, scope \\ nil) do
+    fields = format_fields_for_schema(schema)
+
+    assocs =
+      Enum.map_join(schema.assocs, "\n", fn {_, k, _, _} ->
+        type = if schema.binary_id, do: ":binary_id", else: ":id"
+        "    field #{inspect(k)}, #{type}"
+      end)
+
+    scope_field =
+      if scope do
+        "    field :#{scope.schema_key}, #{inspect(scope.schema_type)}"
+      else
+        ""
+      end
+
+    timestamp_opts =
+      if schema.timestamp_type != :naive_datetime do
+        "type: #{inspect(schema.timestamp_type)}"
+      else
+        ""
+      end
+
+    timestamps = "    timestamps(#{timestamp_opts})"
+
+    schema_fields =
+      [fields, assocs, scope_field]
+      |> join_non_empty("\n")
+
+    [schema_fields, timestamps]
+    |> join_non_empty("\n\n")
+  end
+
+  defp join_non_empty(list, joiner) do
+    list
+    |> Enum.reject(&(&1 == ""))
+    |> Enum.join(joiner)
+  end
+
   @doc """
   Returns the required fields in the schema. Anything not in the `optionals` list
   is considered required.
diff --git a/priv/templates/phx.gen.schema/schema.ex.eex b/priv/templates/phx.gen.schema/schema.ex.eex
index f1aa869144..b1647a1692 100644
--- a/priv/templates/phx.gen.schema/schema.ex.eex
+++ b/priv/templates/phx.gen.schema/schema.ex.eex
@@ -8,11 +8,7 @@ defmodule <%= inspect schema.module %> do
   @foreign_key_type :binary_id<% else %><%= if schema.opts[:primary_key] do %>
   @primary_key {:<%= schema.opts[:primary_key] %>, :id, autogenerate: true}<% end %><% end %>
   schema <%= inspect schema.table %> do
-<%= Mix.Phoenix.Schema.format_fields_for_schema(schema) %>
-<%= for {_, k, _, _} <- schema.assocs do %>    field <%= inspect k %>, <%= if schema.binary_id do %>:binary_id<% else %>:id<% end %>
-<% end %><%= if scope do %>    field :<%= scope.schema_key %>, <%= inspect scope.schema_type %>
-<% end %>
-    timestamps(<%= if schema.timestamp_type != :naive_datetime, do: "type: #{inspect schema.timestamp_type}" %>)
+<%= Mix.Phoenix.Schema.format_schema_body(schema, scope) %>
   end
 
   @doc false
diff --git a/priv/templates/phx.gen.socket/socket.ex.eex b/priv/templates/phx.gen.socket/socket.ex.eex
index d6af581b43..a4fbca117d 100644
--- a/priv/templates/phx.gen.socket/socket.ex.eex
+++ b/priv/templates/phx.gen.socket/socket.ex.eex
@@ -5,11 +5,8 @@ defmodule <%= module %>Socket do
   #
   # It's possible to control the websocket connection and
   # assign values that can be accessed by your channel topics.
-
-  ## Channels<%= if existing_channel do %>
-
-  channel "<%= existing_channel[:singular] %>:*", <%= existing_channel[:module] %>Channel
-<% else %>
+<%= if existing_channel do %>
+  channel "<%= existing_channel[:singular] %>:*", <%= existing_channel[:module] %>Channel<% else %>
   # Uncomment the following line to define a "room:*" topic
   # pointing to the `<%= web_module %>.RoomChannel`:
   #
@@ -20,9 +17,8 @@ defmodule <%= module %>Socket do
   #     mix phx.gen.channel Room
   #
   # See the [`Channels guide`](https://phoenix.hexdocs.pm/channels.html)
-  # for further details.
+  # for further details.<% end %>
 
-<% end %>
   # Socket params are passed from the client and can
   # be used to verify and authenticate a user. After
   # verification, you can put default assigns into
diff --git a/test/mix/tasks/phx.gen.auth_test.exs b/test/mix/tasks/phx.gen.auth_test.exs
index 66574049f2..f6f631f2fe 100644
--- a/test/mix/tasks/phx.gen.auth_test.exs
+++ b/test/mix/tasks/phx.gen.auth_test.exs
@@ -1442,7 +1442,7 @@ defmodule Mix.Tasks.Phx.Gen.AuthTest do
   test "allows templates to be overridden", config do
     in_tmp_phx_project(config.test, fn ->
       File.mkdir_p!("priv/templates/phx.gen.auth")
-      File.write!("priv/templates/phx.gen.auth/auth.ex.eex", "#it works!")
+      File.write!("priv/templates/phx.gen.auth/auth.ex.eex", "#it works!\n")
 
       send(self(), {:mix_shell_input, :yes?, false})
 
diff --git a/test/mix/tasks/phx.gen.schema_test.exs b/test/mix/tasks/phx.gen.schema_test.exs
index 27389d28f3..72a12288f6 100644
--- a/test/mix/tasks/phx.gen.schema_test.exs
+++ b/test/mix/tasks/phx.gen.schema_test.exs
@@ -726,4 +726,51 @@ defmodule Mix.Tasks.Phx.Gen.SchemaTest do
       )
     end)
   end
+
+  describe "format_schema_body/2" do
+    setup do
+      scope = %{schema_key: :user_id, schema_type: :id}
+      {:ok, scope: scope}
+    end
+
+    test "no fields, no assocs, no scope" do
+      schema = Schema.new("Blog.Post", "posts", [], [])
+      assert Schema.format_schema_body(schema) == "    timestamps()"
+    end
+
+    test "with fields, no assocs, no scope" do
+      schema = Schema.new("Blog.Post", "posts", ["title:string"], [])
+      assert Schema.format_schema_body(schema) == "    field :title, :string\n\n    timestamps()"
+    end
+
+    test "no fields, with assocs, no scope" do
+      schema = Schema.new("Blog.Comment", "comments", ["post_id:references:posts"], [])
+      assert Schema.format_schema_body(schema) == "    field :post_id, :id\n\n    timestamps()"
+    end
+
+    test "no fields, no assocs, with scope", %{scope: scope} do
+      schema = Schema.new("Blog.Post", "posts", [], [])
+      assert Schema.format_schema_body(schema, scope) == "    field :user_id, :id\n\n    timestamps()"
+    end
+
+    test "with fields, with assocs, no scope" do
+      schema = Schema.new("Blog.Comment", "comments", ["title:string", "post_id:references:posts"], [])
+      assert Schema.format_schema_body(schema) == "    field :title, :string\n    field :post_id, :id\n\n    timestamps()"
+    end
+
+    test "with fields, no assocs, with scope", %{scope: scope} do
+      schema = Schema.new("Blog.Post", "posts", ["title:string"], [])
+      assert Schema.format_schema_body(schema, scope) == "    field :title, :string\n    field :user_id, :id\n\n    timestamps()"
+    end
+
+    test "no fields, with assocs, with scope", %{scope: scope} do
+      schema = Schema.new("Blog.Comment", "comments", ["post_id:references:posts"], [])
+      assert Schema.format_schema_body(schema, scope) == "    field :post_id, :id\n    field :user_id, :id\n\n    timestamps()"
+    end
+
+    test "with fields, with assocs, with scope", %{scope: scope} do
+      schema = Schema.new("Blog.Comment", "comments", ["title:string", "post_id:references:posts"], [])
+      assert Schema.format_schema_body(schema, scope) == "    field :title, :string\n    field :post_id, :id\n    field :user_id, :id\n\n    timestamps()"
+    end
+  end
 end
diff --git a/usage-rules/elixir.md b/usage-rules/elixir.md
index 63af87f1ad..79c4082236 100644
--- a/usage-rules/elixir.md
+++ b/usage-rules/elixir.md
@@ -52,4 +52,3 @@
       assert_receive {:DOWN, ^ref, :process, ^pid, :normal}
 
    - Instead of sleeping to synchronize before the next call, **always** use `_ = :sys.get_state/1` to ensure the process has handled prior messages
-