Allow extending word selections to non-word chars

Author: kovidgoyal

Diff for: docs/changelog.rst

@@ -136,9 +136,8 @@ To update |kitty|, :doc:`follow the instructions <binary>`.
 - X11: use the window manager's native full-screen implementation when
   making windows full-screen (:iss:`1605`)
 
-- Mouse selection: When extending by word, fix selection encompassing one or
-  two non-word characters after a word when the mouse is over that character
-  (:iss:`1616`)
+- Mouse selection: When extending by word, fix extending selection to non-word
+  characters not working well (:iss:`1616`)
 
 0.13.3 [2019-01-19]
 ------------------------------

Diff for: kitty/mouse.c

@@ -309,7 +309,7 @@ multi_click(Window *w, unsigned int count) {
     unsigned int y1 = w->mouse_pos.cell_y, y2 = w->mouse_pos.cell_y;
     switch(count) {
         case 2:
-            found_selection = screen_selection_range_for_word(screen, w->mouse_pos.cell_x, &y1, &y2, &start, &end);
+            found_selection = screen_selection_range_for_word(screen, w->mouse_pos.cell_x, &y1, &y2, &start, &end, true);
             mode = EXTEND_WORD;
             break;
         case 3:

Diff for: kitty/screen.c

@@ -2007,13 +2007,17 @@ is_opt_word_char(char_type ch) {
 }
 
 bool
-screen_selection_range_for_word(Screen *self, index_type x, index_type *y1, index_type *y2, index_type *s, index_type *e) {
+screen_selection_range_for_word(Screen *self, index_type x, index_type *y1, index_type *y2, index_type *s, index_type *e, bool initial_selection) {
     if (*y1 >= self->lines || x >= self->columns) return false;
     index_type start, end;
     Line *line = visual_line_(self, *y1);
     *y2 = *y1;
 #define is_ok(x) (is_word_char((line->cpu_cells[x].ch)) || is_opt_word_char(line->cpu_cells[x].ch))
-    if (!is_ok(x)) return false;
+    if (!is_ok(x)) {
+        if (initial_selection) return false;
+        *s = x; *e = x;
+        return true;
+    }
     start = x; end = x;
     while(true) {
         while(start > 0 && is_ok(start - 1)) start--;
@@ -2109,19 +2113,19 @@ screen_update_selection(Screen *self, index_type x, index_type y, bool ended) {
     switch(self->selection.extend_mode) {
         case EXTEND_WORD: {
             index_type y1 = y, y2;
-            found = screen_selection_range_for_word(self, x, &y1, &y2, &start, &end);
+            found = screen_selection_range_for_word(self, x, &y1, &y2, &start, &end, false);
             if (found) {
                 if (extending_leftwards) {
                     self->selection.end_x = start; self->selection.end_y = y1;
                     y1 = self->selection.start_y;
-                    found = screen_selection_range_for_word(self, self->selection.start_x, &y1, &y2, &start, &end);
+                    found = screen_selection_range_for_word(self, self->selection.start_x, &y1, &y2, &start, &end, false);
                     if (found) {
                         self->selection.start_x = end; self->selection.start_y = y2;
                     }
                 } else {
                     self->selection.end_x = end; self->selection.end_y = y2;
                     y1 = self->selection.start_y;
-                    found = screen_selection_range_for_word(self, self->selection.start_x, &y1, &y2, &start, &end);
+                    found = screen_selection_range_for_word(self, self->selection.start_x, &y1, &y2, &start, &end, false);
                     if (found) {
                         self->selection.start_x = start; self->selection.start_y = y1;
                     }

Diff for: kitty/screen.h

@@ -181,7 +181,7 @@ bool screen_invert_colors(Screen *self);
 void screen_update_cell_data(Screen *self, void *address, FONTS_DATA_HANDLE, bool cursor_has_moved);
 bool screen_is_cursor_visible(Screen *self);
 bool screen_selection_range_for_line(Screen *self, index_type y, index_type *start, index_type *end);
-bool screen_selection_range_for_word(Screen *self, index_type x, index_type *, index_type *, index_type *start, index_type *end);
+bool screen_selection_range_for_word(Screen *self, index_type x, index_type *, index_type *, index_type *start, index_type *end, bool);
 void screen_start_selection(Screen *self, index_type x, index_type y, bool, SelectionExtendMode);
 void screen_update_selection(Screen *self, index_type x, index_type y, bool ended);
 bool screen_history_scroll(Screen *self, int amt, bool upwards);