Add import_file/1 and /2 helpers

Author: alco

lib/iex/lib/iex/helpers.ex

@@ -25,6 +25,7 @@ defmodule IEx.Helpers do
   * `t/1` — prints type information
   * `v/0` - prints all commands and values
   * `v/1` - retrieves nth value from console
+  * `import_file/1`, `import_file/2` - evaluate the given file in the shell's context
 
   Help for functions in this module can be consulted
   directly from the command line, as an example, try:
@@ -375,4 +376,44 @@ defmodule IEx.Helpers do
         representation
     end
   end
+
+  @doc """
+  Evaluates the contents of file at `path` as if it were directly typed into
+  the shell. When `relative_to` is provided, `path` is treated as being
+  relative to that (unless it is already an absolute path). See `Path.expand`
+  for more details.
+
+  Both `path` and `relative_to` (if present) have to be literal binaries.
+
+  Leading `~` in `path` and `relative_to` is automatically expanded.
+
+  ## Examples
+
+      # ~/file.exs
+      value = 13
+
+      # in the shell
+      iex(1)> import_file "~/file.exs"
+      13
+      iex(2)> value
+      13
+  """
+  defmacro import_file(path, relative_to // nil)
+
+  defmacro import_file(path, relative_to)
+      when is_binary(path) and (nil?(relative_to) or is_binary(relative_to)) do
+    if relative_to do
+      inject_file Path.expand(path, relative_to)
+    else
+      inject_file Path.expand(path)
+    end
+  end
+
+  defmacro import_file(_, _) do
+    raise "import_file expects literal binaries as its arguments"
+  end
+
+  defp inject_file(path) do
+    Code.string_to_ast! File.read!(path), file: path
+  end
 end

lib/iex/lib/iex/server.ex

@@ -98,13 +98,16 @@ defmodule IEx.Server do
     else
       try do
         code = File.read!(path)
+        scope = :elixir.scope_for_eval(config.scope, file: path)
 
         # Evaluate the contents in the same environment do_loop will run in
         { _result, binding, scope } =
           :elixir.eval(:unicode.characters_to_list(code),
                        config.binding,
                        0,
-                       config.scope)
+                       scope)
+
+        scope = :elixir.scope_for_eval(scope, file: "iex")
         config.binding(binding).scope(scope)
       rescue
         exception ->