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().

6 files changed, 30 insertions, 43 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;
diff --git a/src/parser.c b/src/parser.c
index 4e42833..b1aa06e 100644
--- a/src/parser.c
+++ b/src/parser.c
@@ -35,7 +35,6 @@
 #include "ring.h"
 #include "glob.h"
 #include "error.h"
-#include "cmdline.h"
 #include "core-commands.h"
 #include "goto-commands.h"
 #include "parser.h"
@@ -907,15 +906,9 @@ teco_machine_stringbuilding_clear(teco_machine_stringbuilding_t *ctx)
 gboolean
 teco_state_expectstring_initial(teco_machine_main_t *ctx, GError **error)
 {
-	if (ctx->mode > TECO_MODE_NORMAL)
-		return TRUE;
-
-	/*
-	 * 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_default_codepage();
+	if (ctx->mode == TECO_MODE_NORMAL)
+		teco_machine_stringbuilding_set_codepage(&ctx->expectstring.machine,
+		                                         teco_default_codepage());
 	return TRUE;
 }
 
diff --git a/src/parser.h b/src/parser.h
index 29b96b6..88de830 100644
--- a/src/parser.h
+++ b/src/parser.h
@@ -23,6 +23,7 @@
 #include "sciteco.h"
 #include "string-utils.h"
 #include "goto.h"
+#include "undo.h"
 #include "qreg.h"
 
 /*
@@ -282,6 +283,8 @@ struct teco_machine_t {
 	 * Whether side effects must be reverted on rubout.
 	 * State machines created within macro calls don't have to
 	 * even in interactive mode.
+	 * In fact you MUST not revert side effects if this is FALSE
+	 * as the data no longer exists on the call stack at undo-time.
 	 */
 	gboolean must_undo;
 };
@@ -361,6 +364,16 @@ typedef struct teco_machine_stringbuilding_t {
 void teco_machine_stringbuilding_init(teco_machine_stringbuilding_t *ctx, gunichar escape_char,
                                       teco_qreg_table_t *locals, gboolean must_undo);
 
+static inline void
+teco_machine_stringbuilding_set_codepage(teco_machine_stringbuilding_t *ctx,
+                                         guint codepage)
+{
+	/* NOTE: This is not safe to undo in macro calls. */
+	if (ctx->parent.must_undo)
+		teco_undo_guint(ctx->codepage);
+	ctx->codepage = codepage;
+}
+
 void teco_machine_stringbuilding_reset(teco_machine_stringbuilding_t *ctx);
 
 /**
diff --git a/src/qreg-commands.c b/src/qreg-commands.c
index f8bb4cb..cff4c84 100644
--- a/src/qreg-commands.c
+++ b/src/qreg-commands.c
@@ -29,7 +29,6 @@
 #include "interface.h"
 #include "ring.h"
 #include "parser.h"
-#include "cmdline.h"
 #include "core-commands.h"
 #include "qreg.h"
 #include "qreg-commands.h"
@@ -493,12 +492,12 @@ teco_state_setqregstring_building_initial(teco_machine_main_t *ctx, GError **err
 	/*
 	 * The expected codepage of string building constructs is determined
 	 * by the Q-Register.
-	 *
-	 * NOTE: This is not safe to undo in macro calls.
 	 */
-	if (ctx == &teco_cmdline.machine)
-		teco_undo_guint(ctx->expectstring.machine.codepage);
-	return qreg->vtable->get_string(qreg, NULL, NULL, &ctx->expectstring.machine.codepage, error);
+	guint codepage;
+	if (!qreg->vtable->get_string(qreg, NULL, NULL, &codepage, error))
+		return FALSE;
+	teco_machine_stringbuilding_set_codepage(&ctx->expectstring.machine, codepage);
+	return TRUE;
 }
 
 static teco_state_t *
diff --git a/src/search.c b/src/search.c
index 22dc726..0d04895 100644
--- a/src/search.c
+++ b/src/search.c
@@ -35,7 +35,6 @@
 #include "parser.h"
 #include "core-commands.h"
 #include "error.h"
-#include "cmdline.h"
 #include "search.h"
 
 typedef struct {
@@ -61,12 +60,8 @@ teco_state_search_initial(teco_machine_main_t *ctx, GError **error)
 	if (ctx->mode > TECO_MODE_NORMAL)
 		return TRUE;
 
-	/*
-	 * 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 (G_UNLIKELY(!teco_search_qreg_machine))
 		teco_search_qreg_machine = teco_machine_qregspec_new(TECO_QREG_REQUIRED, ctx->qreg_table_locals,
@@ -1052,15 +1047,9 @@ TECO_DEFINE_STATE_SEARCH(teco_state_search_delete);
 static gboolean
 teco_state_replace_insert_initial(teco_machine_main_t *ctx, GError **error)
 {
-	if (ctx->mode > TECO_MODE_NORMAL)
-		return TRUE;
-
-	/*
-	 * 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();
+	if (ctx->mode == TECO_MODE_NORMAL)
+		teco_machine_stringbuilding_set_codepage(&ctx->expectstring.machine,
+		                                         teco_interface_get_codepage());
 	return TRUE;
 }
 
diff --git a/src/spawn.c b/src/spawn.c
index cb1ef75..e6d620c 100644
--- a/src/spawn.c
+++ b/src/spawn.c
@@ -43,7 +43,6 @@
 #include "core-commands.h"
 #include "qreg-commands.h"
 #include "error.h"
-#include "cmdline.h"
 #include "spawn.h"
 
 /*
@@ -168,12 +167,9 @@ teco_state_execute_initial(teco_machine_main_t *ctx, GError **error)
 	/*
 	 * Command-lines and file names are always assumed to be UTF-8,
 	 * unless we set TECO_ED_DEFAULT_ANSI.
-	 *
-	 * 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_default_codepage();
+	teco_machine_stringbuilding_set_codepage(&ctx->expectstring.machine,
+	                                         teco_default_codepage());
 
 	if (!teco_expressions_eval(FALSE, error))
 		return FALSE;