Ensure aliases from macros are properly expanded, closes #1123

Author: José Valim

lib/elixir/lib/macro.ex

@@ -444,7 +444,7 @@ defmodule Macro do
   end
 
   defp expand({ :__aliases__, _, _ } = original, env, cache) do
-    case :elixir_aliases.expand(original, env.aliases, []) do
+    case :elixir_aliases.expand(original, env.aliases, env.macro_aliases) do
       atom when is_atom(atom) -> atom
       aliases ->
         aliases = lc alias inlist aliases, do: expand(alias, env, cache)

lib/elixir/lib/macro/env.ex

@@ -20,6 +20,7 @@ defmodule Macro.Env do
   * `functions` - a list of functions imported from each module
   * `macros` - a list of macros imported from each module
   * `context_modules` - a list of modules defined in the current context
+  * `macro_aliases` - a list of aliases defined inside the current macro
   """
 
   @type name_arity :: { atom, non_neg_integer }
@@ -33,11 +34,12 @@ defmodule Macro.Env do
   @type context_modules :: [module]
 
   fields = [:module, :file, :line, :function, :aliases, :context, :requires,
-            :functions, :macros, :context_modules]
+            :functions, :macros, :context_modules, :macro_aliases]
 
   types  = quote do: [module: module, file: file, line: line,
     function: name_arity, aliases: aliases, requires: requires,
-    functions: functions, macros: macros, context_modules: context_modules]
+    functions: functions, macros: macros, context_modules: context_modules,
+    macro_aliases: aliases]
 
   Record.deffunctions(fields, __MODULE__)
   Record.deftypes(fields, types, __MODULE__)

lib/elixir/src/elixir_scope.erl

@@ -76,18 +76,18 @@ build_ex_var(Line, Key, Name, S) when is_integer(Line) ->
 % Handle Macro.Env conversion
 
 to_erl_env({ 'Elixir.Macro.Env', Module, File, _Line, Function, Aliases, Context,
-    Requires, Functions, Macros, FileModules }) ->
+    Requires, Functions, Macros, ContextModules, MacroAliases }) ->
   #elixir_scope{module=Module,file=File,
     function=Function,aliases=Aliases,context=Context,
     requires=Requires,macros=Macros,functions=Functions,
-    context_modules=FileModules}.
+    context_modules=ContextModules,macro_aliases=MacroAliases}.
 
 to_ex_env({ Line, #elixir_scope{module=Module,file=File,
     function=Function,aliases=Aliases,context=Context,
     requires=Requires,macros=Macros,functions=Functions,
-    context_modules=FileModules} }) when is_integer(Line) ->
+    context_modules=ContextModules,macro_aliases=MacroAliases} }) when is_integer(Line) ->
   { 'Elixir.Macro.Env', Module, File, Line, Function, Aliases,
-    Context, Requires, Functions, Macros, FileModules }.
+    Context, Requires, Functions, Macros, ContextModules, MacroAliases }.
 
 % Provides a tuple with only the scope information we want to serialize.
 

lib/elixir/test/elixir/record_test.exs

@@ -52,6 +52,15 @@ end
 defmodule RecordTest.Macros do
   defrecordp :_user, name: "José", age: 25
 
+  defmacro gen do
+    quote do
+      alias RecordTest.Macros.Nested
+
+      def this_works, do: RecordTest.Macros.Nested[]
+      def this_should_too, do: Nested[]
+    end
+  end
+
   defrecord Nested do
     def nested_record_alias?(Nested[]) do
       true
@@ -96,6 +105,11 @@ end
 defmodule RecordTest do
   use ExUnit.Case, async: true
 
+  # Check the access from the generated macro works
+  # as expected. If it compiles, we are good to go.
+  require RecordTest.Macros
+  RecordTest.Macros.gen
+
   test :record_access_with_nil_keyword do
     record = RecordTest.DynamicName.new(a: nil)
     record_access = RecordTest.DynamicName[a: nil]