vis: implement gv by means of new "^ register

This window local register holds the last active selections.

config.def.h

@@ -247,7 +247,7 @@ static const KeyBinding bindings_normal[] = {
 	{ "g+",                 ACTION(LATER)                               },
 	{ "gn",                 ALIAS("vgn")                                },
 	{ "gN",                 ALIAS("vgN")                                },
-	{ "gv",                 ACTION(SELECTION_RESTORE)                   },
+	{ "gv",                 ALIAS("\"^Sv")                              },
 	{ "I",                  ACTION(INSERT_LINE_START)                   },
 	{ "i",                  ACTION(MODE_INSERT)                         },
 	{ "J",                  ACTION(JOIN_LINES)                          },

main.c

@@ -114,8 +114,6 @@ static const char *movement(Vis*, const char *keys, const Arg *arg);
 static const char *textobj(Vis*, const char *keys, const Arg *arg);
 /* move to the other end of selected text */
 static const char *selection_end(Vis*, const char *keys, const Arg *arg);
-/* restore least recently used selection */
-static const char *selection_restore(Vis*, const char *keys, const Arg *arg);
 /* use register indicated by keys for the current operator */
 static const char *reg(Vis*, const char *keys, const Arg *arg);
 /* perform arg->i motion with a mark indicated by keys as argument */
@@ -265,7 +263,6 @@ enum {
 	VIS_ACTION_PROMPT_SHOW,
 	VIS_ACTION_REPEAT,
 	VIS_ACTION_SELECTION_FLIP,
-	VIS_ACTION_SELECTION_RESTORE,
 	VIS_ACTION_WINDOW_REDRAW_TOP,
 	VIS_ACTION_WINDOW_REDRAW_CENTER,
 	VIS_ACTION_WINDOW_REDRAW_BOTTOM,
@@ -913,11 +910,6 @@ static const KeyAction vis_action[] = {
 		VIS_HELP("Flip selection, move cursor to other end")
 		selection_end,
 	},
-	[VIS_ACTION_SELECTION_RESTORE] = {
-		"vis-selection-restore",
-		VIS_HELP("Restore last selection")
-		selection_restore,
-	},
 	[VIS_ACTION_WINDOW_REDRAW_TOP] = {
 		"vis-window-redraw-top",
 		VIS_HELP("Redraw cursor line at the top of the window")
@@ -2025,19 +2017,6 @@ static const char *selection_end(Vis *vis, const char *keys, const Arg *arg) {
 	return keys;
 }
 
-static const char *selection_restore(Vis *vis, const char *keys, const Arg *arg) {
-	Text *txt = vis_text(vis);
-	View *view = vis_view(vis);
-	for (Selection *s = view_selections(view); s; s = view_selections_next(s))
-		view_selections_restore(s);
-	Filerange sel = view_selection_get(view);
-	if (text_range_is_linewise(txt, &sel))
-		vis_mode_switch(vis, VIS_MODE_VISUAL_LINE);
-	else
-		vis_mode_switch(vis, VIS_MODE_VISUAL);
-	return keys;
-}
-
 static const char *reg(Vis *vis, const char *keys, const Arg *arg) {
 	if (!keys[0])
 		return NULL;

view.c

@@ -49,7 +49,6 @@ struct Selection {
 	Line *line;             /* screen line on which cursor currently resides */
 	int generation;         /* used to filter out newly created cursors during iteration */
 	int number;             /* how many cursors are located before this one */
-	SelectionRegion region; /* saved selection region */
 	View *view;             /* associated view to which this cursor belongs */
 	Selection *prev, *next; /* previous/next cursors ordered by location at creation time */
 };
@@ -1230,11 +1229,6 @@ bool view_selections_set(Selection *s, const Filerange *r) {
 	return true;
 }
 
-void view_selections_save(Selection *s) {
-	s->region.cursor = s->cursor;
-	s->region.anchor = s->anchor;
-}
-
 Filerange view_regions_restore(View *view, SelectionRegion *s) {
 	Text *txt = view->text;
 	size_t anchor = text_mark_get(txt, s->anchor);
@@ -1258,20 +1252,6 @@ bool view_regions_save(View *view, Filerange *r, SelectionRegion *s) {
 	return true;
 }
 
-bool view_selections_restore(Selection *s) {
-	Text *txt = s->view->text;
-	size_t pos = text_mark_get(txt, s->region.cursor);
-	if (pos == EPOS)
-		return false;
-	if (s->region.anchor != s->region.cursor && text_mark_get(txt, s->region.anchor) == EPOS)
-		return false;
-	s->cursor = s->region.cursor;
-	s->anchor = s->region.anchor;
-	s->anchored = true;
-	view_cursors_to(s, pos);
-	return true;
-}
-
 void view_selections_set_all(View *view, Array *arr) {
 	Selection *s;
 	Filerange *r;

view.h

@@ -346,16 +346,6 @@ Filerange view_selection_get(View*);
  * @defgroup view_save
  * @{
  */
-/** Save selection which can later be restored. */
-void view_selections_save(Selection*);
-/**
- * Restore a previously active selection.
- * @rst
- * .. note:: Fails if selection boundaries no longer exist.
- * @endrst
- */
-bool view_selections_restore(Selection*);
-
 Filerange view_regions_restore(View*, SelectionRegion*);
 bool view_regions_save(View*, Filerange*, SelectionRegion*);
 /**

vis-core.h

@@ -162,6 +162,7 @@ struct Win {
 	View *view;             /* currently displayed part of underlying text */
 	RingBuffer *jumplist;   /* LRU jump management */
 	ChangeList changelist;  /* state for iterating through least recently changes */
+	Register reg_selections;/* register used to store selections */
 	Mode modes[VIS_MODE_INVALID]; /* overlay mods used for per window key bindings */
 	Win *parent;            /* window which was active when showing the command prompt */
 	Mode *parent_mode;      /* mode which was active when showing the command prompt */

vis-modes.c

@@ -201,7 +201,8 @@ static void vis_mode_visual_line_enter(Vis *vis, Mode *old) {
 
 static void vis_mode_visual_line_leave(Vis *vis, Mode *new) {
 	if (!new->visual) {
-		window_selection_save(vis->win);
+		if (!vis->action.op)
+			window_selection_save(vis->win);
 		view_selections_clear_all(vis->win->view);
 	} else {
 		view_cursor_to(vis->win->view, view_cursor_get(vis->win->view));
@@ -210,7 +211,8 @@ static void vis_mode_visual_line_leave(Vis *vis, Mode *new) {
 
 static void vis_mode_visual_leave(Vis *vis, Mode *new) {
 	if (!new->visual) {
-		window_selection_save(vis->win);
+		if (!vis->action.op)
+			window_selection_save(vis->win);
 		view_selections_clear_all(vis->win->view);
 	}
 }

vis-registers.c

@@ -221,6 +221,8 @@ enum VisRegister vis_register_used(Vis *vis) {
 }
 
 static Register *register_from(Vis *vis, enum VisRegister id) {
+	if (id == VIS_REG_SELECTION && vis->win)
+		return &vis->win->reg_selections;
 	if (VIS_REG_A <= id && id <= VIS_REG_Z)
 		id = VIS_REG_a + id - VIS_REG_A;
 	if (id < LENGTH(vis->registers))
@@ -300,4 +302,5 @@ const RegisterDef vis_registers[] = {
 	[VIS_REG_COMMAND]    = { ':', VIS_HELP("Last :-command")                                   },
 	[VIS_REG_SHELL]      = { '!', VIS_HELP("Last shell command given to either <, >, |, or !") },
 	[VIS_REG_NUMBER]     = { '#', VIS_HELP("Register number")                                  },
+	[VIS_REG_SELECTION]  = { '^', VIS_HELP("Last selections")                                  },
 };

vis.c

@@ -246,14 +246,10 @@ void vis_window_status(Win *win, const char *status) {
 
 void window_selection_save(Win *win) {
 	Vis *vis = win->vis;
-	File *file = win->file;
-	Filerange sel = view_selections_get(view_selections(win->view));
-	file->marks[VIS_MARK_SELECTION_START] = text_mark_set(file->text, sel.start);
-	file->marks[VIS_MARK_SELECTION_END] = text_mark_set(file->text, sel.end);
-	if (!vis->action.op) {
-		for (Selection *s = view_selections(win->view); s; s = view_selections_next(s))
-			view_selections_save(s);
-	}
+	View *view = win->view;
+	Array sel = view_selections_get_all(view);
+	vis_register_selections_set(vis, VIS_REG_SELECTION, &sel);
+	array_release(&sel);
 }
 
 static void window_free(Win *win) {
@@ -270,6 +266,7 @@ static void window_free(Win *win) {
 	for (size_t i = 0; i < LENGTH(win->modes); i++)
 		map_free(win->modes[i].bindings);
 	ringbuf_free(win->jumplist);
+	register_release(&win->reg_selections);
 	free(win);
 }
 
@@ -467,6 +464,7 @@ Win *window_new_file(Vis *vis, File *file, enum UiOption options) {
 		window_free(win);
 		return NULL;
 	}
+	register_init(&win->reg_selections);
 	file->refcount++;
 	view_options_set(win->view, view_options_get(win->view));
 	view_tabwidth_set(win->view, vis->tabwidth);
@@ -845,6 +843,9 @@ void vis_do(Vis *vis) {
 	if (a->op == &vis_operators[VIS_OP_PUT_AFTER] && multiple_cursors && vis_register_count(vis, reg) == 1)
 		reg_slot = 0;
 
+	if (vis->mode->visual && a->op)
+		window_selection_save(win);
+
 	for (Selection *sel = view_selections(view), *next; sel; sel = next) {
 		if (vis->interrupted)
 			break;
@@ -982,11 +983,8 @@ void vis_do(Vis *vis) {
 			if (pos == EPOS) {
 				view_selections_dispose(sel);
 			} else if (pos <= text_size(txt)) {
-				if (vis->mode->visual)
-					view_selections_save(sel);
+				view_selection_clear(sel);
 				view_cursors_to(sel, pos);
-				if (vis->mode->visual)
-					view_selection_clear(sel);
 			}
 		}
 	}

vis.h

@@ -719,6 +719,7 @@ enum VisRegister {
 	VIS_REG_COMMAND,    /* last used :-command ": */
 	VIS_REG_SHELL,      /* last used shell command given to either <, >, |, or ! */
 	VIS_REG_NUMBER,     /* cursor number */
+	VIS_REG_SELECTION, /* last used selections */
 	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,
 	VIS_REG_k, VIS_REG_l, VIS_REG_m, VIS_REG_n, VIS_REG_o,