Fix bug in for comprehensions

CHANGELOG.md

@@ -5,6 +5,7 @@
 
 * Bug fixes
   * [ExUnit] Ensure doctest failures are properly reported
+  * [Kernel] Fix a bug where comprehensions arguments were not properly take into account in the variable scope
   * [Mix] Fix issue on rebar install when the endpoint was redirecting to a relative uri
 
 * Deprecations

lib/eex/test/eex_test.exs

@@ -282,6 +282,15 @@ foo
     assert_eval "\n\n  Good\n \n", string
   end
 
+  test "for comprehensions" do
+    string = """
+    <%= for _name <- packages || [] do %>
+    <% end %>
+    <%= all || :done %>
+    """
+    assert_eval "\ndone\n", string, packages: nil, all: nil
+  end
+
   test "unicode" do
     template = """
       • <%= "•" %> •
@@ -367,8 +376,8 @@ foo
     assert {:wrapped, "foo"} = EEx.eval_string("foo", [], engine: TestEngine)
   end
 
-  defp assert_eval(expected, actual) do
-    result = EEx.eval_string(actual, [], file: __ENV__.file, engine: EEx.Engine)
+  defp assert_eval(expected, actual, binding \\ []) do
+    result = EEx.eval_string(actual, binding, file: __ENV__.file, engine: EEx.Engine)
     assert result == expected
   end
 end

lib/elixir/src/elixir_for.erl

@@ -69,7 +69,7 @@ translate(Meta, Args, #elixir_scope{return=Return} = RS) ->
 
   {TCases, SC} = translate_gen(Meta, Cases, [], SI),
   {TExpr, SE}  = elixir_translator:translate_block(Expr, Return, SC),
-  SF = elixir_scope:mergef(SI, SE),
+  SF = elixir_scope:mergec(SI, SE),
 
   case comprehension_expr(TInto, TExpr) of
     {inline, TIntoExpr} ->