Conditionally generate child_spec with elixir >= 1.5. Closes phoenixf…

…ramework#2713

installer/lib/phx_new/generator.ex

@@ -102,6 +102,7 @@ defmodule Phx.New.Generator do
       end
 
     binding = [
+      elixir_version: elixir_version(),
       app_name: project.app,
       app_module: inspect(project.app_mod),
       root_app_name: project.root_app,
@@ -127,11 +128,31 @@ defmodule Phx.New.Generator do
       adapter_module: adapter_module,
       adapter_config: adapter_config,
       generators: nil_if_empty(project.generators ++ adapter_generators(adapter_config)),
-      namespaced?: namespaced?(project)]
+      namespaced?: namespaced?(project),
+    ]
 
     %Project{project | binding: binding}
   end
 
+  def stub_elixir_version(vsn, func) do
+    if configured_version() do
+      raise RuntimeError, "race condition detected when trying to stub elixir version"
+    end
+
+    try do
+      Application.put_env(:phoenix, :installer_elixir_vsn, vsn)
+      func.()
+    after
+      Application.delete_env(:phoenix, :installer_elixir_vsn)
+    end
+  end
+
+  defp elixir_version do
+    configured_version() || System.version()
+  end
+
+  defp configured_version, do: Application.get_env(:phoenix, :installer_elixir_vsn)
+
   defp namespaced?(project) do
     Macro.camelize(project.app) != inspect(project.app_mod)
   end

installer/templates/phx_single/lib/app_name/application.ex

@@ -1,8 +1,10 @@
 defmodule <%= app_module %>.Application do
-  use Application
-
   # See https://hexdocs.pm/elixir/Application.html
   # for more information on OTP Applications
+  @moduledoc false
+
+  use Application
+  <%= if Version.match?(elixir_version, "< 1.5.0") do %>
   def start(_type, _args) do
     import Supervisor.Spec
 
@@ -20,7 +22,23 @@ defmodule <%= app_module %>.Application do
     # for other strategies and supported options
     opts = [strategy: :one_for_one, name: <%= app_module %>.Supervisor]
     Supervisor.start_link(children, opts)
-  end
+  end<% else %>
+  def start(_type, _args) do
+    # List all child processes to be supervised
+    children = [<%= if ecto do %>
+      # Start the Ecto repository
+      <%= app_module %>.Repo,<% end %>
+      # Start the endpoint when the application starts
+      <%= endpoint_module %>,
+      # Starts a worker by calling: <%= app_module %>.Worker.start_link(arg)
+      # {<%= app_module %>.Worker, arg},
+    ]
+
+    # See https://hexdocs.pm/elixir/Supervisor.html
+    # for other strategies and supported options
+    opts = [strategy: :one_for_one, name: <%= app_module %>.Supervisor]
+    Supervisor.start_link(children, opts)
+  end<% end %>
 
   # Tell Phoenix to update the endpoint configuration
   # whenever the application is updated.

installer/templates/phx_umbrella/apps/app_name/lib/app_name/application.ex

@@ -8,16 +8,19 @@ defmodule <%= app_module %>.Application do
   for use in channels, controllers, and elsewhere.
   """
   use Application
+  <%= if Version.match?(elixir_version, "< 1.5.0") do %>
+  def start(_type, _args) do<%= if ecto do %>
+    import Supervisor.Spec
 
-  def start(_type, _args) do
-    import Supervisor.Spec, warn: false
-
-    <%= if ecto do %>
     Supervisor.start_link([
       supervisor(<%= app_module %>.Repo, []),
-    ], strategy: :one_for_one, name: <%= app_module %>.Supervisor)
-    <% else %>
-    Supervisor.start_link([], strategy: :one_for_one, name: <%= app_module %>.Supervisor)
-    <% end %>
-  end
+    ], strategy: :one_for_one, name: <%= app_module %>.Supervisor)<% else %>
+    Supervisor.start_link([], strategy: :one_for_one, name: <%= app_module %>.Supervisor)<% end %>
+  end<% else %>
+  def start(_type, _args) do<%= if ecto do %>
+    Supervisor.start_link([
+      <%= app_module %>.Repo,
+    ], strategy: :one_for_one, name: <%= app_module %>.Supervisor)<% else %>
+    Supervisor.start_link([], strategy: :one_for_one, name: <%= app_module %>.Supervisor)<% end %>
+  end<% end %>
 end

installer/templates/phx_umbrella/apps/app_name_web/lib/app_name/application.ex

@@ -1,6 +1,7 @@
 defmodule <%= web_namespace %>.Application do
+  @moduledoc false
   use Application
-
+  <%= if Version.match?(elixir_version, "< 1.5.0") do %>
   def start(_type, _args) do
     import Supervisor.Spec
 
@@ -16,7 +17,21 @@ defmodule <%= web_namespace %>.Application do
     # for other strategies and supported options
     opts = [strategy: :one_for_one, name: <%= web_namespace %>.Supervisor]
     Supervisor.start_link(children, opts)
-  end
+  end<% else %>
+  def start(_type, _args) do
+    # List all child processes to be supervised
+    children = [
+      # Start the endpoint when the application starts
+      <%= endpoint_module %>,
+      # Starts a worker by calling: <%= web_namespace %>.Worker.start_link(arg)
+      # {<%= web_namespace %>.Worker, arg},
+    ]
+
+    # See https://hexdocs.pm/elixir/Supervisor.html
+    # for other strategies and supported options
+    opts = [strategy: :one_for_one, name: <%= web_namespace %>.Supervisor]
+    Supervisor.start_link(children, opts)
+  end<% end %>
 
   # Tell Phoenix to update the endpoint configuration
   # whenever the application is updated.

installer/test/phx_new_test.exs

@@ -1,7 +1,7 @@
 Code.require_file "mix_helper.exs", __DIR__
 
 defmodule Mix.Tasks.Phx.NewTest do
-  use ExUnit.Case
+  use ExUnit.Case, async: false
   import MixHelper
   import ExUnit.CaptureIO
 
@@ -19,6 +19,42 @@ defmodule Mix.Tasks.Phx.NewTest do
     assert_received {:mix_shell, :info, ["Phoenix v" <> _]}
   end
 
+  test "new with elixir >= 1.5 child_spec", config do
+    in_tmp to_string(config.test), fn ->
+      Phx.New.Generator.stub_elixir_version("1.5.0", fn ->
+        Mix.Tasks.Phx.New.run([@app_name])
+
+        assert_file "phx_blog/lib/phx_blog/application.ex", fn file ->
+          assert file =~ """
+              children = [
+                # Start the Ecto repository
+                PhxBlog.Repo,
+                # Start the endpoint when the application starts
+                PhxBlogWeb.Endpoint,
+          """
+        end
+      end)
+    end
+  end
+
+  test "new with elixir < 1.5 child_spec", config do
+    in_tmp to_string(config.test), fn ->
+      Phx.New.Generator.stub_elixir_version("1.3.0", fn ->
+        Mix.Tasks.Phx.New.run([@app_name])
+
+        assert_file "phx_blog/lib/phx_blog/application.ex", fn file ->
+          assert file =~ """
+              children = [
+                # Start the Ecto repository
+                supervisor(PhxBlog.Repo, []),
+                # Start the endpoint when the application starts
+                supervisor(PhxBlogWeb.Endpoint, []),
+          """
+        end
+      end)
+    end
+  end
+
   test "new with defaults" do
     in_tmp "new with defaults", fn ->
       Mix.Tasks.Phx.New.run([@app_name])

installer/test/phx_new_umbrella_test.exs

@@ -1,7 +1,7 @@
 Code.require_file "mix_helper.exs", __DIR__
 
 defmodule Mix.Tasks.Phx.New.UmbrellaTest do
-  use ExUnit.Case, async: true
+  use ExUnit.Case, async: false
   import MixHelper
 
   @app "phx_umb"
@@ -29,6 +29,104 @@ defmodule Mix.Tasks.Phx.New.UmbrellaTest do
     Path.join(["#{app}_umbrella/apps/#{app}_web", path])
   end
 
+  describe "new umbrella with elixir >= 1.5 child_spec" do
+    test "with defaults", config do
+      in_tmp to_string(config.test), fn ->
+        Phx.New.Generator.stub_elixir_version("1.5.0", fn ->
+          Mix.Tasks.Phx.New.run([@app, "--umbrella"])
+
+          assert_file app_path(@app, "lib/#{@app}/application.ex"), fn file ->
+            assert file =~ """
+              def start(_type, _args) do
+                Supervisor.start_link([
+                  PhxUmb.Repo,
+                ], strategy: :one_for_one, name: PhxUmb.Supervisor)
+              end
+            """
+          end
+
+          assert_file web_path(@app, "lib/#{@app}_web/application.ex"), fn file ->
+            assert file =~ """
+                children = [
+                  # Start the endpoint when the application starts
+                  PhxUmbWeb.Endpoint,
+                  # Starts a worker by calling: PhxUmbWeb.Worker.start_link(arg)
+                  # {PhxUmbWeb.Worker, arg},
+                ]
+            """
+          end
+        end)
+      end
+    end
+
+    test "without ecto", config do
+      in_tmp to_string(config.test), fn ->
+        Phx.New.Generator.stub_elixir_version("1.5.0", fn ->
+          Mix.Tasks.Phx.New.run([@app, "--umbrella", "--no-ecto"])
+
+          assert_file app_path(@app, "lib/#{@app}/application.ex"), fn file ->
+            refute file =~ "children ="
+            assert file =~ """
+              def start(_type, _args) do
+                Supervisor.start_link([], strategy: :one_for_one, name: PhxUmb.Supervisor)
+              end
+            """
+          end
+        end)
+      end
+    end
+  end
+
+  describe "new umbrella with elixir < 1.5" do
+    test "with defaults", config do
+      in_tmp to_string(config.test), fn ->
+        Phx.New.Generator.stub_elixir_version("1.3.0", fn ->
+          Mix.Tasks.Phx.New.run([@app, "--umbrella"])
+
+          assert_file app_path(@app, "lib/#{@app}/application.ex"), fn file ->
+            assert file =~ """
+              def start(_type, _args) do
+                import Supervisor.Spec
+
+                Supervisor.start_link([
+                  supervisor(PhxUmb.Repo, []),
+                ], strategy: :one_for_one, name: PhxUmb.Supervisor)
+              end
+            """
+          end
+
+          assert_file web_path(@app, "lib/#{@app}_web/application.ex"), fn file ->
+            assert file =~ """
+                children = [
+                  # Start the endpoint when the application starts
+                  supervisor(PhxUmbWeb.Endpoint, []),
+                  # Start your own worker by calling: PhxUmbWeb.Worker.start_link(arg1, arg2, arg3)
+                  # worker(PhxUmbWeb.Worker, [arg1, arg2, arg3]),
+                ]
+            """
+          end
+        end)
+      end
+    end
+
+    test "without ecto", config do
+      in_tmp to_string(config.test), fn ->
+        Phx.New.Generator.stub_elixir_version("1.3.0", fn ->
+          Mix.Tasks.Phx.New.run([@app, "--umbrella", "--no-ecto"])
+
+          assert_file app_path(@app, "lib/#{@app}/application.ex"), fn file ->
+            refute file =~ "children ="
+            assert file =~ """
+              def start(_type, _args) do
+                Supervisor.start_link([], strategy: :one_for_one, name: PhxUmb.Supervisor)
+              end
+            """
+          end
+        end)
+      end
+    end
+  end
+
   test "new with umbrella and defaults" do
     in_tmp "new with umbrella and defaults", fn ->
       Mix.Tasks.Phx.New.run([@app, "--umbrella"])
@@ -73,7 +171,7 @@ defmodule Mix.Tasks.Phx.New.UmbrellaTest do
       end
 
       assert_file app_path(@app, "lib/#{@app}/application.ex"), ~r/defmodule PhxUmb.Application do/
-      assert_file app_path(@app, "lib/#{@app}/application.ex"), ~r/supervisor\(PhxUmb.Repo, \[\]\)/
+      assert_file app_path(@app, "lib/#{@app}/application.ex"), ~r/PhxUmb.Repo/
       assert_file app_path(@app, "lib/#{@app}.ex"), ~r/defmodule PhxUmb do/
       assert_file app_path(@app, "mix.exs"), ~r/mod: {PhxUmb.Application, \[\]}/
       assert_file app_path(@app, "test/test_helper.exs")