instead of relying on Scintilla undo actions, use SciTECO undo tokens exclusivelyHEADmaster-fmsbw-cimaster

Previously we were using both Scintilla undo actions and our own undo tokens
and both had to be coordinated via `undo__teco_interface_ssm(SCI_UNDO, 0, 0)`.
This was error prone since we have to predict when an undo action is actually
generated. Furthermore, you had to update SCI_SETUNDOCOLLECTION on all buffers
and the Q-Reg view whenever switching to and from interactive mode.
Also, this probably wasted memory for the doubled undo bookkeeping.
Now, we always set SCI_SETUNDOCOLLECTION(FALSE), even in interactive mode.
teco_undo_view_insert() was introduced to undo text deletions.
While this saves almost no lines of code, it's just a clearer and simpler
architecture.

1 files changed, 7 insertions, 5 deletions

diff --git a/src/spawn.c b/src/spawn.c
index a4bf381..933d8f4 100644
--- a/src/spawn.c
+++ b/src/spawn.c
@@ -422,10 +422,16 @@ teco_state_execute_done(teco_machine_main_t *ctx, teco_string_t str, GError **er
 		teco_interface_ssm(SCI_GOTOPOS, teco_spawn_ctx.to, 0);
 	}
 
-	teco_interface_ssm(SCI_BEGINUNDOACTION, 0, 0);
 	teco_spawn_ctx.start = teco_spawn_ctx.from;
 	g_main_loop_run(teco_spawn_ctx.mainloop);
 	if (!teco_spawn_ctx.register_argument) {
+		if (teco_current_doc_must_undo()) {
+			undo__teco_interface_ssm(SCI_DELETERANGE, teco_spawn_ctx.to,
+			                         teco_interface_ssm(SCI_GETCURRENTPOS, 0, 0)-teco_spawn_ctx.to);
+			teco_undo_interface_insert(teco_spawn_ctx.from,
+			                           teco_spawn_ctx.to - teco_spawn_ctx.from);
+		}
+
 		teco_interface_ssm(SCI_DELETERANGE, teco_spawn_ctx.from,
 		                   teco_spawn_ctx.to - teco_spawn_ctx.from);
 
@@ -437,7 +443,6 @@ teco_state_execute_done(teco_machine_main_t *ctx, teco_string_t str, GError **er
 
 		teco_current_doc_set_dot(to);
 	}
-	teco_interface_ssm(SCI_ENDUNDOACTION, 0, 0);
 
 	if (teco_spawn_ctx.register_argument) {
 		if (teco_spawn_ctx.stdout_reader.eol_style >= 0) {
@@ -446,9 +451,6 @@ teco_state_execute_done(teco_machine_main_t *ctx, teco_string_t str, GError **er
 			                       teco_spawn_ctx.stdout_reader.eol_style);
 		}
 	} else if (teco_spawn_ctx.from != teco_spawn_ctx.to || teco_spawn_ctx.text_added) {
-		/* undo action has only been created if it changed anything */
-		if (teco_current_doc_must_undo())
-			undo__teco_interface_ssm(SCI_UNDO, 0, 0);
 		teco_ring_dirtify();
 	}