From 4940073e9223f419dafd0538cc157d9e8f7ca7b2 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jos=C3=A9=20Valim?= <jose.valim@plataformatec.com.br>
Date: Tue, 9 Oct 2018 20:35:34 +0200
Subject: [PATCH] Include optional dependencies in extra_applications

Previously when using optional dependencies, they would
not be automatically included by compile.app in extra_applications.

This meant that an optional dependency would not be guaranteed
to be started before the application. Forcing users to handle
this logic in an ad-hoc fashion that is incompatible with
releases.
---
 lib/mix/lib/mix/dep.ex                      | 13 ++++-------
 lib/mix/lib/mix/tasks/compile.app.ex        |  7 +++---
 lib/mix/test/mix/dep_test.exs               | 25 ---------------------
 lib/mix/test/mix/tasks/compile.app_test.exs |  2 +-
 4 files changed, 8 insertions(+), 39 deletions(-)

diff --git a/lib/mix/lib/mix/dep.ex b/lib/mix/lib/mix/dep.ex
index 16b89680845..c14e2be82d7 100644
--- a/lib/mix/lib/mix/dep.ex
+++ b/lib/mix/lib/mix/dep.ex
@@ -131,18 +131,13 @@ defmodule Mix.Dep do
       for dep <- deps,
           dep.app == app,
           child <- dep.deps,
-          do: {child.app, Keyword.get(child.opts, :optional, false)},
+          do: {child.app, true},
           into: %{}
 
-    Enum.map(children, fn %{app: app, opts: opts} = dep ->
-      # optional only matters at the top level. Any non-top level dependency
-      # that is optional and is still available means it has been fulfilled.
+    Enum.map(children, fn %{app: app} = dep ->
       case top_level do
-        %{^app => optional} ->
-          %{dep | top_level: true, opts: Keyword.put(opts, :optional, optional)}
-
-        %{} ->
-          %{dep | top_level: false, opts: Keyword.delete(opts, :optional)}
+        %{^app => _} -> %{dep | top_level: true}
+        %{} -> %{dep | top_level: false}
       end
     end)
   end
diff --git a/lib/mix/lib/mix/tasks/compile.app.ex b/lib/mix/lib/mix/tasks/compile.app.ex
index d02f5cb92ac..dbe6dd4e043 100644
--- a/lib/mix/lib/mix/tasks/compile.app.ex
+++ b/lib/mix/lib/mix/tasks/compile.app.ex
@@ -208,7 +208,7 @@ defmodule Mix.Tasks.Compile.App do
     apps =
       properties
       |> Keyword.get(:applications)
-      |> Kernel.||(apps_from_prod_non_optional_deps(properties, config))
+      |> Kernel.||(apps_from_prod_deps(properties, config))
       |> normalize_apps(extra, config)
 
     Keyword.put(properties, :applications, apps)
@@ -313,12 +313,11 @@ defmodule Mix.Tasks.Compile.App do
     end)
   end
 
-  defp apps_from_prod_non_optional_deps(properties, config) do
+  defp apps_from_prod_deps(properties, config) do
     included_applications = Keyword.get(properties, :included_applications, [])
     non_runtime_deps = non_runtime_deps(config)
 
-    for %{app: app, opts: opts, top_level: true} <- Mix.Dep.cached(),
-        not Keyword.get(opts, :optional, false),
+    for %{app: app, top_level: true} <- Mix.Dep.cached(),
         not Map.has_key?(non_runtime_deps, app),
         app not in included_applications,
         do: app
diff --git a/lib/mix/test/mix/dep_test.exs b/lib/mix/test/mix/dep_test.exs
index afa7de6fdcb..71cbfd0c152 100644
--- a/lib/mix/test/mix/dep_test.exs
+++ b/lib/mix/test/mix/dep_test.exs
@@ -525,31 +525,6 @@ defmodule Mix.DepTest do
     end)
   end
 
-  test "nested deps with optional matching" do
-    Process.put(:custom_deps_git_repo_opts, optional: true)
-
-    # deps_repo brings git_repo but it is optional
-    deps = [
-      {:deps_repo, "0.1.0", path: "custom/deps_repo"},
-      {:git_repo, "0.1.0", git: MixTest.Case.fixture_path("git_repo")}
-    ]
-
-    with_deps(deps, fn ->
-      in_fixture("deps_status", fn ->
-        File.mkdir_p!("custom/deps_repo/lib")
-
-        File.write!("custom/deps_repo/lib/a.ex", """
-        # Check that the child dependency is top_level and optional
-        [%Mix.Dep{app: :git_repo, top_level: true, opts: opts}] = Mix.Dep.cached()
-        true = Keyword.fetch!(opts, :optional)
-        """)
-
-        Mix.Tasks.Deps.Get.run([])
-        Mix.Tasks.Deps.Compile.run([])
-      end)
-    end)
-  end
-
   test "nested deps considers runtime from current app" do
     Process.put(:custom_deps_git_repo_opts, runtime: false)
 
diff --git a/lib/mix/test/mix/tasks/compile.app_test.exs b/lib/mix/test/mix/tasks/compile.app_test.exs
index 618b5af8418..1caaf502e40 100644
--- a/lib/mix/test/mix/tasks/compile.app_test.exs
+++ b/lib/mix/test/mix/tasks/compile.app_test.exs
@@ -99,7 +99,7 @@ defmodule Mix.Tasks.Compile.AppTest do
       properties = parse_resource_file(:custom_deps)
 
       assert properties[:applications] ==
-               [:kernel, :stdlib, :elixir, :logger, :ok1, :ok3, :ok4, :ok7]
+               [:kernel, :stdlib, :elixir, :logger, :ok1, :ok3, :ok4, :ok6, :ok7]
     end)
   end