Clean deps when deps.compile is run with --force (#4780)

Signed-off-by: José Valim <[email protected]>

Author: felipesere

lib/mix/lib/mix/tasks/deps.compile.ex

@@ -33,7 +33,7 @@ defmodule Mix.Tasks.Deps.Compile do
   import Mix.Dep, only: [loaded: 1, available?: 1, loaded_by_name: 2,
                          make?: 1, mix?: 1]
 
-  @switches [include_children: :boolean]
+  @switches [include_children: :boolean, force: :boolean]
 
   @spec run(OptionParser.argv) :: :ok
   def run(args) do
@@ -44,18 +44,18 @@ defmodule Mix.Tasks.Deps.Compile do
     Mix.Project.get!
 
     case OptionParser.parse(args, switches: @switches) do
-      {_, [], _} ->
+      {opts, [], _} ->
         # Because this command may be invoked explicitly with
         # deps.compile, we simply try to compile any available
         # dependency.
-        compile(Enum.filter(loaded(env: Mix.env), &available?/1))
+        compile(Enum.filter(loaded(env: Mix.env), &available?/1), opts)
       {opts, tail, _} ->
-        compile(loaded_by_name(tail, [env: Mix.env] ++ opts))
+        compile(loaded_by_name(tail, [env: Mix.env] ++ opts), opts)
     end
   end
 
   @doc false
-  def compile(deps) do
+  def compile(deps, options \\ []) do
     shell  = Mix.shell
     config = Mix.Project.deps_config
 
@@ -65,6 +65,8 @@ defmodule Mix.Tasks.Deps.Compile do
       Enum.map(deps, fn %Mix.Dep{app: app, status: status, opts: opts, scm: scm} = dep ->
         check_unavailable!(app, status)
 
+        clean(app, options)
+
         compiled? = cond do
           not is_nil(opts[:compile]) ->
             do_compile dep, config
@@ -93,6 +95,12 @@ defmodule Mix.Tasks.Deps.Compile do
     if true in compiled, do: Mix.Dep.Lock.touch_manifest, else: :ok
   end
 
+  defp clean(app, opts) do
+    if Keyword.get(opts, :force, false) do
+      File.rm_rf! Path.join [Mix.Project.build_path, "lib", Atom.to_string(app)]
+    end
+  end
+
   defp touch_fetchable(scm, path) do
     if scm.fetchable? do
       File.mkdir_p!(path)

lib/mix/test/mix/tasks/deps_test.exs

@@ -193,6 +193,20 @@ defmodule Mix.Tasks.DepsTest do
 
   ## deps.unlock
 
+  test "cleans and recompiles artifacts if --force given" do
+    Mix.Project.push SuccessfulDepsApp
+
+    in_fixture "deps_status", fn ->
+      Mix.Tasks.Deps.Compile.run []
+      File.touch! "_build/dev/lib/ok/clean-me"
+
+      Mix.Tasks.Deps.Compile.run ["--force"]
+      refute File.exists? "_build/dev/lib/ok/clean-me"
+    end
+  end
+
+  ## deps.unlock
+
   test "unlocks all deps", context do
     Mix.Project.push DepsApp
     in_tmp context.test, fn ->