fixup: use teco_machine_t::must_undo instead of trying to identify the current state machine

* The previous solution was not wrong, but unnecessarily complex. We already have a flag
  for exactly this purpose.
* Avoid redundancies by introducing teco_machine_stringbuilding_set_codepage().

1 files changed, 2 insertions, 5 deletions

diff --git a/src/core-commands.c b/src/core-commands.c
index befb6e8..0cde7e0 100644
--- a/src/core-commands.c
+++ b/src/core-commands.c
@@ -2759,12 +2759,9 @@ teco_state_insert_initial(teco_machine_main_t *ctx, GError **error)
 	/*
 	 * Current document's encoding determines the behaviour of
 	 * string building constructs.
-	 *
-	 * NOTE: This is not safe to undo in macro calls.
 	 */
-	if (ctx == &teco_cmdline.machine)
-		teco_undo_guint(ctx->expectstring.machine.codepage);
-	ctx->expectstring.machine.codepage = teco_interface_get_codepage();
+	teco_machine_stringbuilding_set_codepage(&ctx->expectstring.machine,
+	                                         teco_interface_get_codepage());
 
 	if (!teco_expressions_eval(FALSE, error))
 		return FALSE;