Consolidate protocols on demand on reloader, closes #1253

lib/phoenix/code_reloader/server.ex

@@ -62,37 +62,53 @@ defmodule Phoenix.CodeReloader.Server do
   end
 
   defp mix_compile(paths, compilers) do
-    reloadable_paths = Enum.flat_map(paths, &["--elixirc-paths", &1])
+    opts = Enum.flat_map(paths, &["--elixirc-paths", &1])
     Enum.each compilers, &Mix.Task.reenable("compile.#{&1}")
 
     {res, out} =
       proxy_io(fn ->
         try do
-          # We call build_structure mostly for Windows
-          # so any new assets in priv is copied to the
-          # build directory.
+          # We call build_structure mostly for Windows so any
+          # new assets in priv is copied to the build directory.
           Mix.Project.build_structure
-          Enum.each compilers, &Mix.Task.run("compile.#{&1}", reloadable_paths)
+          res = Enum.flat_map(compilers, &mix_compile_each(&1, opts))
+
+          if :ok in res && consolidate_protocols? do
+            Mix.Task.reenable("compile.protocols")
+            Mix.Task.run("compile.protocols")
+          else
+            res
+          end
         catch
           _, _ -> :error
         end
       end)
 
-    cond do
-      :error in res -> {:error, out}
-      :ok in res    -> :ok
-      true          -> :noop
+    case res do
+      :error -> {:error, out}
+      :noop -> :noop
+      _ -> :ok
     end
   end
 
+  defp mix_compile_each(compiler, opts) do
+    # We always wrap in a list because Mix.Task.run
+    # will return a list in case of umbrella applications.
+    List.wrap(Mix.Task.run("compile.#{compiler}", opts))
+  end
+
+  defp consolidate_protocols? do
+    Mix.Project.config[:consolidate_protocols]
+  end
+
   defp proxy_io(fun) do
     original_gl = Process.group_leader
     {:ok, proxy_gl} = Proxy.start()
     Process.group_leader(self(), proxy_gl)
 
     try do
       res = fun.()
-      {List.wrap(res), Proxy.stop(proxy_gl)}
+      {res, Proxy.stop(proxy_gl)}
     after
       Process.group_leader(self(), original_gl)
       Process.exit(proxy_gl, :kill)