Add option :all to :no_warn_undefined (#9691)

Author: wojtekmach

lib/elixir/lib/code.ex

@@ -1018,8 +1018,8 @@ defmodule Code do
 
     * `:no_warn_undefined` (since v1.10.0) - list of modules and `{Mod, fun, arity}`
       tuples that will not emit warnings that the module or function does not exist
-      at compilation time. This can be useful when doing dynamic compilation.
-      Defaults to `[]`.
+      at compilation time. Pass atom `:all` to skip warning for all undefined
+      functions. This can be useful when doing dynamic compilation. Defaults to `[]`.
 
     * `:tracers` (since v1.10.0) - a list of tracers (modules) to be used during
       compilation. See the module docs for more information. Defaults to `[]`.
@@ -1049,6 +1049,16 @@ defmodule Code do
     :ok
   end
 
+  def put_compiler_option(:no_warn_undefined, value) do
+    if value != :all and not is_list(value) do
+      raise "compiler option :no_warn_undefined should be a list or the atom :all, " <>
+              "got: #{inspect(value)}"
+    end
+
+    :elixir_config.put(:no_warn_undefined, value)
+    :ok
+  end
+
   def put_compiler_option(key, value) when key in @list_compiler_options do
     if not is_list(value) do
       raise "compiler option #{inspect(key)} should be a list, got: #{inspect(value)}"

lib/elixir/lib/module/checker.ex

@@ -75,13 +75,11 @@ defmodule Module.Checker do
   end
 
   defp undefined_and_deprecation_warnings(map, cache) do
-    no_warn_undefined = map.no_warn_undefined ++ Code.get_compiler_option(:no_warn_undefined)
-
     state = %{
       cache: cache,
       file: map.file,
       module: map.module,
-      no_warn_undefined: no_warn_undefined,
+      no_warn_undefined: merge_no_warn_undefined(map),
       function: nil,
       warnings: []
     }
@@ -93,6 +91,16 @@ defmodule Module.Checker do
     |> sort_warnings()
   end
 
+  defp merge_no_warn_undefined(map) do
+    case Code.get_compiler_option(:no_warn_undefined) do
+      :all ->
+        :all
+
+      list when is_list(list) ->
+        map.no_warn_undefined ++ list
+    end
+  end
+
   defp check_definitions(definitions, state) do
     Enum.reduce(definitions, state, &check_definition/2)
   end
@@ -211,6 +219,10 @@ defmodule Module.Checker do
   defp warn_undefined?(:erlang, :orelse, 2, _state), do: false
   defp warn_undefined?(:erlang, :andalso, 2, _state), do: false
 
+  defp warn_undefined?(_, _, _, %{no_warn_undefined: :all}) do
+    false
+  end
+
   defp warn_undefined?(module, fun, arity, state) do
     not Enum.any?(state.no_warn_undefined, &(&1 == module or &1 == {module, fun, arity}))
   end

lib/elixir/test/elixir/module/checker_test.exs

@@ -535,6 +535,49 @@ defmodule Module.CheckerTest do
         Code.compiler_options(no_warn_undefined: no_warn_undefined)
       end
     end
+
+    test "global no_warn_undefined :all" do
+      no_warn_undefined = Code.get_compiler_option(:no_warn_undefined)
+
+      try do
+        Code.compiler_options(no_warn_undefined: :all)
+
+        files = %{
+          "a.ex" => """
+          defmodule A do
+            def a, do: MissingModule.func(1)
+          end
+          """
+        }
+
+        assert_no_warnings(files)
+      after
+        Code.compiler_options(no_warn_undefined: no_warn_undefined)
+      end
+    end
+
+    test "global no_warn_undefined :all and local exclude" do
+      no_warn_undefined = Code.get_compiler_option(:no_warn_undefined)
+
+      try do
+        Code.compiler_options(no_warn_undefined: :all)
+
+        files = %{
+          "a.ex" => """
+          defmodule A do
+            @compile {:no_warn_undefined, MissingModule}
+
+            def a, do: MissingModule.func(1)
+            def b, do: MissingModule2.func(1, 2)
+          end
+          """
+        }
+
+        assert_no_warnings(files)
+      after
+        Code.compiler_options(no_warn_undefined: no_warn_undefined)
+      end
+    end
   end
 
   describe "deprecated" do

lib/mix/lib/mix/cli.ex

@@ -37,7 +37,10 @@ defmodule Mix.CLI do
     file = System.get_env("MIX_EXS") || "mix.exs"
 
     if File.regular?(file) do
+      old_value = Code.get_compiler_option(:no_warn_undefined)
+      Code.put_compiler_option(:no_warn_undefined, :all)
       Code.compile_file(file)
+      Code.put_compiler_option(:no_warn_undefined, old_value)
     end
   end