vis: convert gn and gN text objects to use "/ register content

vis-core.h

@@ -146,7 +146,6 @@ struct Vis {
 	Macro *recording, *last_recording;   /* currently (if non NULL) and least recently recorded macro */
 	Macro *macro_operator;               /* special macro used to repeat certain operators */
 	Mode *mode_before_prompt;            /* user mode which was active before entering prompt */
-	Regex *search_pattern;               /* last used search pattern */
 	char search_char[8];                 /* last used character to search for via 'f', 'F', 't', 'T' */
 	int last_totill;                     /* last to/till movement used for ';' and ',' */
 	int tabwidth;                        /* how many spaces should be used to display a tab */

vis-text-objects.c

@@ -31,11 +31,21 @@ bool vis_textobject(Vis *vis, enum VisTextObject id) {
 }
 
 static Filerange search_forward(Vis *vis, Text *txt, size_t pos) {
-	return text_object_search_forward(txt, pos, vis->search_pattern);
+	Filerange range = text_range_empty();
+	Regex *regex = vis_regex(vis, NULL);
+	if (regex)
+		range = text_object_search_forward(txt, pos, regex);
+	text_regex_free(regex);
+	return range;
 }
 
 static Filerange search_backward(Vis *vis, Text *txt, size_t pos) {
-	return text_object_search_backward(txt, pos, vis->search_pattern);
+	Filerange range = text_range_empty();
+	Regex *regex = vis_regex(vis, NULL);
+	if (regex)
+		range = text_object_search_backward(txt, pos, regex);
+	text_regex_free(regex);
+	return range;
 }
 
 const TextObject vis_textobjects[] = {

vis.c

@@ -335,8 +335,6 @@ Vis *vis_new(Ui *ui, VisEvent *event) {
 	vis->registers[VIS_REG_BLACKHOLE].type = REGISTER_BLACKHOLE;
 	vis->registers[VIS_REG_CLIPBOARD].type = REGISTER_CLIPBOARD;
 	action_reset(&vis->action);
-	if (!(vis->search_pattern = text_regex_new()))
-		goto err;
 	if (!(vis->command_file = file_new_internal(vis, NULL)))
 		goto err;
 	if (!(vis->search_file = file_new_internal(vis, NULL)))
@@ -364,7 +362,6 @@ void vis_free(Vis *vis) {
 		vis_window_close(vis->windows);
 	file_free(vis, vis->command_file);
 	file_free(vis, vis->search_file);
-	text_regex_free(vis->search_pattern);
 	for (int i = 0; i < LENGTH(vis->registers); i++)
 		register_release(&vis->registers[i]);
 	vis->ui->free(vis->ui);

vis.h

@@ -352,7 +352,7 @@ enum VisRegister {
 	VIS_REG_PROMPT,  /* internal register which shadows DEFAULT in PROMPT mode */
 	VIS_MACRO_OPERATOR,      /* records entered keys after an operator */
 	VIS_MACRO_REPEAT,        /* copy of the above macro once the recording is finished */
-	VIS_REG_SEARCH,
+	VIS_REG_SEARCH,  /* last used search pattern "/ */
 	VIS_REG_INVALID, /* has to be the last 'real' register */
 	VIS_REG_A, VIS_REG_B, VIS_REG_C, VIS_REG_D, VIS_REG_E,
 	VIS_REG_F, VIS_REG_G, VIS_REG_H, VIS_REG_I, VIS_REG_J,