fixed rubbing out <:Xq>, <:^Uq> and other append-to-register operations

* This was a regression introduced in 41ab5cf0289dab60ac1ddc97cf9680ee2468ea6c,
  which changed the semantics of teco_doc_undo_set_string().
* Removed undo_append_string() Q-Reg virtual method.
  append_string() now does its own undo token emission, so that we can
  defer the teco_doc_undo_edit() after the point that the document
  was initialized. This is important, so that we can configure the
  default encoding on new registers.

4 files changed, 29 insertions, 31 deletions

diff --git a/src/qreg-commands.c b/src/qreg-commands.c
index 5b80d15..6fb68f2 100644
--- a/src/qreg-commands.c
+++ b/src/qreg-commands.c
@@ -408,8 +408,7 @@ teco_state_setqregstring_nobuilding_done(teco_machine_main_t *ctx,
 
 		if (colon_modified) {
 			/* append to register */
-			if (!qreg->vtable->undo_append_string(qreg, error) ||
-			    !qreg->vtable->append_string(qreg, buffer, len, error))
+			if (!qreg->vtable->append_string(qreg, buffer, len, error))
 				return NULL;
 		} else {
 			/* set register */
@@ -422,8 +421,7 @@ teco_state_setqregstring_nobuilding_done(teco_machine_main_t *ctx,
 
 	if (args > 0 || colon_modified) {
 		/* append to register */
-		if (!qreg->vtable->undo_append_string(qreg, error) ||
-		    !qreg->vtable->append_string(qreg, str->data, str->len, error))
+		if (!qreg->vtable->append_string(qreg, str->data, str->len, error))
 			return NULL;
 	} else {
 		/* set register */
@@ -790,8 +788,7 @@ teco_state_copytoqreg_got_register(teco_machine_main_t *ctx, teco_qreg_t *qreg,
 	teco_interface_ssm(SCI_GETTEXTRANGEFULL, 0, (sptr_t)&range);
 
 	if (teco_machine_main_eval_colon(ctx)) {
-		if (!qreg->vtable->undo_append_string(qreg, error) ||
-		    !qreg->vtable->append_string(qreg, str, len, error))
+		if (!qreg->vtable->append_string(qreg, str, len, error))
 			return NULL;
 	} else {
 		guint cp = teco_interface_get_codepage();
diff --git a/src/qreg.c b/src/qreg.c
index a0e5415..487a725 100644
--- a/src/qreg.c
+++ b/src/qreg.c
@@ -183,6 +183,20 @@ teco_qreg_plain_append_string(teco_qreg_t *qreg, const gchar *str, gsize len, GE
 	if (!len)
 		return TRUE;
 
+	if (qreg->must_undo) { // FIXME
+		/*
+		 * Necessary, so that upon rubout the
+		 * string's parameters are restored.
+		 */
+		teco_doc_update(&qreg->string, teco_qreg_view);
+
+		if (teco_qreg_current && teco_qreg_current->must_undo) // FIXME
+			teco_doc_undo_edit(&teco_qreg_current->string);
+
+		teco_doc_undo_reset(&qreg->string);
+		undo__teco_view_ssm(teco_qreg_view, SCI_UNDO, 0, 0);
+	}
+
 	if (teco_qreg_current)
 		teco_doc_update(&teco_qreg_current->string, teco_qreg_view);
 
@@ -194,6 +208,15 @@ teco_qreg_plain_append_string(teco_qreg_t *qreg, const gchar *str, gsize len, GE
 
 	if (teco_qreg_current)
 		teco_doc_edit(&teco_qreg_current->string, 0);
+
+	/*
+	 * Make sure these undo tokens are only generated now,
+	 * so that teco_doc_edit() always initializes the document and
+	 * the default codepage.
+	 */
+	if (qreg->must_undo) // FIXME
+		teco_doc_undo_edit(&qreg->string);
+
 	return TRUE;
 }
 
@@ -354,7 +377,6 @@ teco_qreg_plain_save(teco_qreg_t *qreg, const gchar *filename, GError **error)
 	.set_string		= teco_qreg_plain_set_string, \
 	.undo_set_string	= teco_qreg_plain_undo_set_string, \
 	.append_string		= teco_qreg_plain_append_string, \
-	.undo_append_string	= teco_qreg_plain_undo_set_string, \
 	.get_string		= teco_qreg_plain_get_string, \
 	.get_character		= teco_qreg_plain_get_character, \
 	.get_length		= teco_qreg_plain_get_length, \
@@ -567,12 +589,6 @@ teco_qreg_bufferinfo_append_string(teco_qreg_t *qreg, const gchar *str, gsize le
 	return FALSE;
 }
 
-static gboolean
-teco_qreg_bufferinfo_undo_append_string(teco_qreg_t *qreg, GError **error)
-{
-	return TRUE;
-}
-
 /*
  * NOTE: The `string` component is currently unused on the "*" register.
  */
@@ -609,7 +625,6 @@ teco_qreg_bufferinfo_new(void)
 		.set_string		= teco_qreg_bufferinfo_set_string,
 		.undo_set_string	= teco_qreg_bufferinfo_undo_set_string,
 		.append_string		= teco_qreg_bufferinfo_append_string,
-		.undo_append_string	= teco_qreg_bufferinfo_undo_append_string,
 		.get_string		= teco_qreg_bufferinfo_get_string,
 		/*
 		 * As teco_qreg_bufferinfo_set_string() is not implemented,
@@ -671,12 +686,6 @@ teco_qreg_workingdir_append_string(teco_qreg_t *qreg, const gchar *str, gsize le
 }
 
 static gboolean
-teco_qreg_workingdir_undo_append_string(teco_qreg_t *qreg, GError **error)
-{
-	return TRUE;
-}
-
-static gboolean
 teco_qreg_workingdir_get_string(teco_qreg_t *qreg, gchar **str, gsize *len,
                                 guint *codepage, GError **error)
 {
@@ -709,7 +718,6 @@ teco_qreg_workingdir_new(void)
 		.set_string		= teco_qreg_workingdir_set_string,
 		.undo_set_string	= teco_qreg_workingdir_undo_set_string,
 		.append_string		= teco_qreg_workingdir_append_string,
-		.undo_append_string	= teco_qreg_workingdir_undo_append_string,
 		.get_string		= teco_qreg_workingdir_get_string
 	);
 
@@ -779,12 +787,6 @@ teco_qreg_clipboard_append_string(teco_qreg_t *qreg, const gchar *str, gsize len
 }
 
 static gboolean
-teco_qreg_clipboard_undo_append_string(teco_qreg_t *qreg, GError **error)
-{
-	return TRUE;
-}
-
-static gboolean
 teco_qreg_clipboard_undo_set_string(teco_qreg_t *qreg, GError **error)
 {
 	/*
@@ -878,7 +880,6 @@ teco_qreg_clipboard_new(const gchar *name)
 		.set_string		= teco_qreg_clipboard_set_string,
 		.undo_set_string	= teco_qreg_clipboard_undo_set_string,
 		.append_string		= teco_qreg_clipboard_append_string,
-		.undo_append_string	= teco_qreg_clipboard_undo_append_string,
 		.get_string		= teco_qreg_clipboard_get_string,
 		.load			= teco_qreg_clipboard_load
 	);
diff --git a/src/qreg.h b/src/qreg.h
index f5866e7..59cf2cc 100644
--- a/src/qreg.h
+++ b/src/qreg.h
@@ -52,8 +52,9 @@ typedef const struct {
 	gboolean (*set_string)(teco_qreg_t *qreg, const gchar *str, gsize len,
 	                       guint codepage, GError **error);
 	gboolean (*undo_set_string)(teco_qreg_t *qreg, GError **error);
+
+	/* does not need an explicit undo-call */
 	gboolean (*append_string)(teco_qreg_t *qreg, const gchar *str, gsize len, GError **error);
-	gboolean (*undo_append_string)(teco_qreg_t *qreg, GError **error);
 
 	gboolean (*get_string)(teco_qreg_t *qreg, gchar **str, gsize *len,
 	                       guint *codepage, GError **error);
diff --git a/src/spawn.c b/src/spawn.c
index 06fdf95..7a5736c 100644
--- a/src/spawn.c
+++ b/src/spawn.c
@@ -761,8 +761,7 @@ teco_spawn_stdout_watch_cb(GIOChannel *chan, GIOCondition condition, gpointer da
 
 		if (qreg) {
 			if (teco_spawn_ctx.text_added) {
-				if (!qreg->vtable->undo_append_string(qreg, &teco_spawn_ctx.error) ||
-				    !qreg->vtable->append_string(qreg, buffer.data, buffer.len,
+				if (!qreg->vtable->append_string(qreg, buffer.data, buffer.len,
 				                                 &teco_spawn_ctx.error))
 					goto error;
 			} else {