Fix bug in surround_context alias handling (#12830)

Author: sabiwara

lib/elixir/lib/code/fragment.ex

@@ -753,7 +753,7 @@ defmodule Code.Fragment do
  end
  end
 
- defp take_alias([h | t], acc) when h in ?A..?Z or h in ?a..?z or h in ?0..9 or h == ?_,
+ defp take_alias([h | t], acc) when h in ?A..?Z or h in ?a..?z or h in ?0..?9 or h == ?_,
  do: take_alias(t, [h | acc])
 
  defp take_alias(rest, acc) do

lib/elixir/test/elixir/code_fragment_test.exs

@@ -738,6 +738,14 @@ defmodule CodeFragmentTest do
  end: {3, 5}
  }
  end
+
+ for i <- 1..11 do
+ assert CF.surround_context("Foo.Bar.Baz.foo(bar)", {1, i}) == %{
+ context: {:alias, ~c"Foo.Bar.Baz"},
+ begin: {1, 1},
+ end: {1, 12}
+ }
+ end
  end
 
  test "underscored special forms" do