vis: implement number increment <C-a> and decrement <C-x> functionality

The default key bindings are not changed for now, because <C-a>
conflicts with multiple cursor alignment.

1 files changed, 59 insertions, 0 deletions

diff --git a/main.c b/main.c
index 918f4c8..c3ae7a3 100644
--- a/main.c
+++ b/main.c
@@ -109,6 +109,8 @@ static const char *window(Vis*, const char *keys, const Arg *arg);
 static const char *unicode_info(Vis*, const char *keys, const Arg *arg);
 /* either go to count % of ile or to matching item */
 static const char *percent(Vis*, const char *keys, const Arg *arg);
+/* either increment (arg->i > 0) or decrement (arg->i < 0) number under cursor */
+static const char *number_increment_decrement(Vis*, const char *keys, const Arg *arg);
 
 enum {
 	VIS_ACTION_EDITOR_SUSPEND,
@@ -268,6 +270,8 @@ enum {
 	VIS_ACTION_MOTION_CHARWISE,
 	VIS_ACTION_MOTION_LINEWISE,
 	VIS_ACTION_UNICODE_INFO,
+	VIS_ACTION_NUMBER_INCREMENT,
+	VIS_ACTION_NUMBER_DECREMENT,
 	VIS_ACTION_NOP,
 };
 
@@ -1057,6 +1061,16 @@ static KeyAction vis_action[] = {
 		"Show Unicode codepoint(s) of character under cursor",
 		unicode_info,
 	},
+	[VIS_ACTION_NUMBER_INCREMENT] = {
+		"number-increment",
+		"Increment number under cursor",
+		number_increment_decrement, { .i = +1 }
+	},
+	[VIS_ACTION_NUMBER_DECREMENT] = {
+		"number-decrement",
+		"Decrement number under cursor",
+		number_increment_decrement, { .i = -1 }
+	},
 	[VIS_ACTION_NOP] = {
 		"nop",
 		"Ignore key, do nothing",
@@ -1618,6 +1632,51 @@ static const char *percent(Vis *vis, const char *keys, const Arg *arg) {
 	return keys;
 }
 
+static const char *number_increment_decrement(Vis *vis, const char *keys, const Arg *arg) {
+	View *view = vis_view(vis);
+	Text *txt = vis_text(vis);
+
+	int delta = arg->i;
+	int count = vis_count_get(vis);
+	if (count != 0 && count != VIS_COUNT_UNKNOWN)
+		delta *= count;
+
+	for (Cursor *c = view_cursors(view); c; c = view_cursors_next(c)) {
+		Filerange r = text_object_number(txt, view_cursors_pos(c));
+		if (!text_range_valid(&r))
+			continue;
+		char *buf = text_bytes_alloc0(txt, r.start, text_range_size(&r));
+		if (buf) {
+			char *number = buf, fmt[255];
+			if (number[0] == '-')
+				number++;
+			bool octal = number[0] == '0' && ('0' <= number[1] && number[1] <= '7');
+			bool hex = number[0] == '0' && (number[1] == 'x' || number[1] == 'X');
+			bool dec = !hex && !octal;
+
+			long long value = strtoll(buf, NULL, 0);
+			value += delta;
+			if (dec) {
+				snprintf(fmt, sizeof fmt, "%lld", value);
+			} else if (hex) {
+				size_t len = strlen(number) - 2;
+				snprintf(fmt, sizeof fmt, "0x%0*llx", len, value);
+			} else {
+				size_t len = strlen(number) - 1;
+				snprintf(fmt, sizeof fmt, "0%0*llo", len, value);
+			}
+			text_delete_range(txt, &r);
+			text_insert(txt, r.start, fmt, strlen(fmt));
+			view_cursors_to(c, r.start);
+		}
+		free(buf);
+	}
+
+	vis_cancel(vis);
+
+	return keys;
+}
+
 static Vis *vis;
 
 static void signal_handler(int signum, siginfo_t *siginfo, void *context) {