Move from module_not_found to the more generic handler_not_found

Author: José Valim

lib/elixir/lib/gen_event.ex

@@ -435,7 +435,7 @@ defmodule GenEvent do
 
   The return value `reply` is defined in the return value of `handle_call/2`.
   If the specified event handler is not installed, the function returns
-  `{:error, :module_not_found}`.
+  `{:error, :handler_not_found}`.
   """
   @spec call(manager, handler, term, timeout) ::  term | {:error, term}
   def call(manager, handler, request, timeout \\ 5000) do
@@ -454,7 +454,7 @@ defmodule GenEvent do
 
   The event manager will call `terminate/2` to terminate the event handler
   and return the callback value. If the specified event handler is not
-  installed, the function returns `{:error, :module_not_found}`.
+  installed, the function returns `{:error, :handler_not_found}`.
   """
   @spec remove_handler(manager, handler, term) :: term | {:error, term}
   def remove_handler(manager, handler, args) do
@@ -874,7 +874,7 @@ defmodule GenEvent do
   defp server_call(module, query, handlers, name) do
     case :lists.keyfind(module, handler(:id) + 1, handlers) do
       false ->
-        {false, {:error, :module_not_found}, handlers}
+        {false, {:error, :handler_not_found}, handlers}
       handler ->
         case server_call_update(handler, query, name, handlers) do
           {{hib, handler}, reply} ->
@@ -996,7 +996,7 @@ defmodule GenEvent do
       {:value, handler, handlers} ->
         {do_terminate(handler, args, last_in, name, reason), handlers}
       false ->
-        {{:error, :module_not_found}, handlers}
+        {{:error, :handler_not_found}, handlers}
     end
   end
 

lib/elixir/test/elixir/gen_event_test.exs

@@ -18,8 +18,8 @@ defmodule GenEventTest do
       raise "oops"
     end
 
-    def init({:swap, {:error, :module_not_found}}) do
-      {:error, :module_not_found_on_swap}
+    def init({:swap, {:error, :handler_not_found}}) do
+      {:error, :handler_not_found_on_swap}
     end
 
     def init({:swap, parent}) when is_pid(parent) do
@@ -291,15 +291,15 @@ defmodule GenEventTest do
     GenEvent.add_handler(pid, ReplyHandler, {self(), false}, monitor: true)
 
     assert GenEvent.remove_handler(pid, {ReplyHandler, self()}, :ok) ==
-           {:error, :module_not_found}
+           {:error, :handler_not_found}
     assert GenEvent.remove_handler(pid, ReplyHandler, :ok) ==
            {:terminate, :ok}
     assert_receive {:terminate, :ok}
 
     GenEvent.add_handler(pid, {ReplyHandler, self()}, {self(), false}, monitor: true)
 
     assert GenEvent.remove_handler(pid, ReplyHandler, :ok) ==
-           {:error, :module_not_found}
+           {:error, :handler_not_found}
     assert {:error, {%RuntimeError{}, _}} =
            GenEvent.remove_handler(pid, {ReplyHandler, self()}, :raise)
 
@@ -326,7 +326,7 @@ defmodule GenEventTest do
     # The handler is initialized even when the module does not exist
     # on swap. However, in this case, we are returning an error on init.
     assert GenEvent.swap_handler(pid, ReplyHandler, :swapped, ReplyHandler, :swap) ==
-           {:error, :module_not_found_on_swap}
+           {:error, :handler_not_found_on_swap}
   end
 
   test "notify/2" do
@@ -475,7 +475,7 @@ defmodule GenEventTest do
 
     assert GenEvent.add_handler(pid, DefaultHandler, []) == :ok
     assert GenEvent.call(pid, UnknownHandler, :messages) ==
-            {:error, :module_not_found}
+            {:error, :handler_not_found}
     assert GenEvent.call(pid, DefaultHandler, :whatever) ==
             {:error, {:bad_call, :whatever}}
     assert GenEvent.which_handlers(pid) == []

lib/logger/test/logger_test.exs

@@ -34,7 +34,7 @@ defmodule LoggerTest do
     assert :ok = Logger.remove_backend(:console)
     assert Application.get_env(:logger, :backends) == []
     assert Logger.remove_backend(:console) ==
-           {:error, :module_not_found}
+           {:error, :handler_not_found}
 
     assert capture_log(fn ->
       assert Logger.debug("hello", []) == :ok