Ensure c helper works with full path

Author: José Valim

lib/iex/lib/iex/helpers.ex

@@ -69,7 +69,7 @@ defmodule IEx.Helpers do
       raise ArgumentError, message: "expected a binary or a list of binaries as argument"
     end
 
-    { found, not_found } = Enum.map(files, &Path.join(path, &1)) |> Enum.partition(&File.exists?/1)
+    { found, not_found } = Enum.map(files, &Path.expand(&1, path)) |> Enum.partition(&File.exists?/1)
 
     unless Enum.empty?(not_found) do
       IO.puts IEx.color(:eval_error, %s[Cannot find #{Enum.join(not_found, ", ")}])
@@ -82,7 +82,8 @@ defmodule IEx.Helpers do
 
     modules = Enum.map(erls, fn(source) ->
       { module, binary } = compile_erlang(source)
-      File.write!(Path.join(path, source), binary)
+      base = source |> Path.basename |> Path.rootname
+      File.write!(Path.join(path, base <> ".beam"), binary)
       module
     end)
 

lib/iex/test/iex/helpers_test.exs

@@ -207,6 +207,16 @@ defmodule IEx.HelpersTest do
     cleanup_modules([Sample])
   end
 
+  test "c helper with full path" do
+    filename = "sample.ex"
+    with_file filename, test_module_code, fn ->
+      assert c(Path.expand(filename)) == [Sample]
+      assert Sample.run == :run
+    end
+  after
+    cleanup_modules([Sample])
+  end
+
   test "c helper multiple modules" do
     assert_raise UndefinedFunctionError, "undefined function: Sample.run/0", fn ->
       Sample.run