Remove compile-time warnings

Author: josevalim

lib/elixir/lib/exception.ex

@@ -1694,7 +1694,8 @@ defmodule UndefinedFunctionError do
 
   For example:
 
-      iex> String.non_existing_fun("hello")
+      # Let's use apply/3 as otherwise Elixir emits a compile-time warning
+      iex> apply(String, :non_existing_fun, ["hello"])
       ** (UndefinedFunctionError) function String.non_existing_fun/1 is undefined or private
 
   The following fields of this exception are public and can be accessed freely:

lib/elixir/test/elixir/exception_test.exs

@@ -14,24 +14,14 @@ defmodule ExceptionTest do
   doctest Exception
 
   doctest RuntimeError
-  doctest ArgumentError
-  doctest ArithmeticError
   doctest SystemLimitError
   doctest MismatchedDelimiterError
   doctest SyntaxError
   doctest TokenMissingError
-  doctest BadFunctionError
-  doctest BadMapError
   doctest BadBooleanError
-  doctest MatchError
-  doctest CaseClauseError
-  doctest WithClauseError
-  doctest CondClauseError
-  doctest TryClauseError
   doctest UndefinedFunctionError
   doctest FunctionClauseError
   doctest Protocol.UndefinedError
-  doctest KeyError
   doctest UnicodeConversionError
   doctest Enum.OutOfBoundsError
   doctest Enum.EmptyError

lib/elixir/test/elixir/kernel/raise_test.exs

@@ -409,12 +409,9 @@ defmodule Kernel.RaiseTest do
     end
 
     test "badfun error" do
-      # Avoid "invalid function call" warning
-      x = fn -> :example end
-
       result =
         try do
-          x.().(2)
+          Process.get(:unused, :example).(2)
         rescue
           x in [BadFunctionError] -> Exception.message(x)
         end
@@ -537,12 +534,10 @@ defmodule Kernel.RaiseTest do
     end
 
     test "try clause error" do
-      f = fn -> :example end
-
       result =
         try do
           try do
-            f.()
+            Process.get(:unused, :example)
           rescue
             _exception ->
               :ok