Backwards incompatible change on before_compile and after_compile

Both callbacks now receive the environment as
first argument instead of the module.

Author: José Valim

CHANGELOG.md

@@ -11,6 +11,9 @@
 * bug fix
   * [Mix] Allow Mix projects to be generated with just one letter
 
+* backwards incompatible changes
+  * [Kernel] `before_compile` and `after_compile` callbacks now receive the environment as first argument instead of the module
+
 * deprecations
   * [Kernel] Tidy up and clean `quote` API
   * [Kernel] Old `:local.(args)` syntax is deprecated

lib/elixir/src/elixir_def.erl

@@ -110,8 +110,8 @@ run_on_definition_callbacks(Kind, Line, Module, Name, Args, Guards, Expr, S, CO)
       ok;
     _ ->
       Env = elixir_scope:to_ex_env({ Line, S }),
-      Callbacks = 'Elixir.Module':get_attribute(Module, on_definition),
-      [Mod:Fun(Env, Kind, Name, Args, Guards, Expr) || { Mod, Fun } <- Callbacks]
+      elixir_module:eval_callbacks(Line, Module, on_definition,
+        [Env, Kind, Name, Args, Guards, Expr], S)
   end.
 
 %% Retrieve @file or fallback to default

lib/elixir/src/elixir_dispatch.erl

@@ -155,7 +155,7 @@ expand_require(Meta, Receiver, { Name, Arity } = Tuple, Args, Module, Function,
 %% Expansion helpers
 
 expand_macro_fun(Meta, Fun, Receiver, Name, Args, Module, Requires, SEnv) ->
-  case (Receiver == Module) or is_element(Receiver, Requires) of
+  case (Receiver == Module) or is_element(Receiver, Requires) or skip_requires(SEnv) of
     true  -> ok;
     false ->
       Tuple = { unrequired_module, { Receiver, Name, length(Args), Requires } },
@@ -192,6 +192,9 @@ translate_expansion(Meta, Tree, S) ->
 
 %% Helpers
 
+skip_requires(#elixir_scope{check_requires=false}) -> true;
+skip_requires(_) -> false.
+
 find_dispatch(Tuple, [{ Name, Values }|T]) ->
   case is_element(Tuple, Values) of
     true  -> Name;

lib/elixir/src/elixir_module.erl

@@ -1,5 +1,6 @@
 -module(elixir_module).
--export([translate/4, compile/5, data_table/1, eval_quoted/4, format_error/1]).
+-export([translate/4, compile/5, data_table/1, eval_quoted/4,
+         format_error/1, eval_callbacks/5]).
 -include("elixir.hrl").
 -compile({parse_transform, elixir_transform}).
 
@@ -133,7 +134,8 @@ eval_form(Line, Module, Block, Vars, RawS) ->
   S = scope_for_eval(Module, RawS),
   { Value, NewS } = elixir_compiler:eval_forms([Block], Line, Vars, S),
   elixir_def_overridable:store_pending(Module),
-  eval_callbacks(Line, Module, before_compile, [Module], NewS),
+  Env = elixir_scope:to_ex_env({ Line, S }),
+  eval_callbacks(Line, Module, before_compile, [Env], NewS),
   elixir_def_overridable:store_pending(Module),
   Value.
 
@@ -238,7 +240,8 @@ spec_for_macro(Else) -> Else.
 load_form(Line, Forms, S) ->
   elixir_compiler:module(Forms, S, fun(Module, Binary) ->
     EvalS = scope_for_eval(Module, S),
-    eval_callbacks(Line, Module, after_compile, [Module, Binary], EvalS),
+    Env = elixir_scope:to_ex_env({ Line, EvalS }),
+    eval_callbacks(Line, Module, after_compile, [Env, Binary], EvalS),
 
     case get(elixir_compiled) of
       Current when is_list(Current) ->
@@ -321,20 +324,16 @@ else_clause() ->
 % HELPERS
 
 eval_callbacks(Line, Module, Name, Args, RawS) ->
-  S         = RawS#elixir_scope{check_clauses=false},
+  S         = RawS#elixir_scope{check_clauses=false,check_requires=false},
   Binding   = binding_for_eval(Module, []),
   Callbacks = lists:reverse(ets:lookup_element(data_table(Module), Name, 2)),
-  Requires  = S#elixir_scope.requires,
   Meta      = [{line,Line}],
 
   lists:foreach(fun({M,F}) ->
-    Expr  = { { '.', Meta, [M,F] }, Meta, Args },
-    Scope = case ordsets:is_element(M, Requires) of
-      true  -> S;
-      false -> S#elixir_scope{requires=ordsets:add_element(M, Requires)}
-    end,
-
-    { Tree, _ } = elixir_translator:translate_each(Expr, Scope),
+    { Tree, _ } = elixir_dispatch:dispatch_require(Meta, M, F, Args, S, fun() ->
+      apply(M, F, Args),
+      { { nil, 0 }, S }
+    end),
 
     try
       erl_eval:exprs([Tree], Binding)

lib/elixir/test/elixir/kernel/errors_test.exs

@@ -270,7 +270,7 @@ defmodule Kernel.ErrorsTest do
   end
 
   test :macros_compiled_callback do
-    assert [{Kernel.ErrorsTest,:__before_compile__,[Foo],_}|_] =
+    assert [{Kernel.ErrorsTest,:__before_compile__,[Macro.Env[module: Foo]],_}|_] =
       rescue_stacktrace("defmodule Foo do\nModule.put_attribute(__MODULE__, :before_compile, Kernel.ErrorsTest)\nend")
   end
 

lib/elixir/test/elixir/module_test.exs

@@ -16,12 +16,12 @@ defmodule ModuleTest.ToBeUsed do
     quote do: (def before_compile, do: true)
   end
 
-  defmacro __after_compile__(ModuleTest.ToUse, bin) when is_binary(bin) do
+  defmacro __after_compile__(Macro.Env[module: ModuleTest.ToUse], bin) when is_binary(bin) do
     # IO.puts "HELLO"
   end
 
-  defmacro callback(target) do
-    value = Module.get_attribute(target, :has_callback)
+  defmacro callback(env) do
+    value = Module.get_attribute(env.module, :has_callback)
     quote do
       name  = :original_value
       args  = [1]

lib/mix/lib/mix/project.ex

@@ -40,8 +40,8 @@ defmodule Mix.Project do
 
   # Invoked after each Mix.Project is compiled.
   @doc false
-  def __after_compile__(module, _binary) do
-    push module
+  def __after_compile__(env, _binary) do
+    push env.module
   end
 
   # Push a project into the project stack. Only