Fix a regression in the previous release that caused empty lines to be skipped when copying text from a selection

Fixes #8435

docs/changelog.rst

@@ -101,6 +101,8 @@ Detailed list of changes
 
 - A new option :opt:`clear_selection_on_clipboard_loss` to clear selections when they no longer reflect the contents of the clipboard
 
+- Fix a regression in the previous release that caused empty lines to be skipped when copying text from a selection (:iss:`8435`)
+
 - Fix flickering of hyperlink underline when client program continuously
   redraws on mouse movement (:iss:`8414`)
 

kitty/screen.c

@@ -3580,7 +3580,8 @@ text_for_range(Screen *self, const Selection *sel, bool insert_newlines, bool st
         const bool is_first_line = y == min_y, is_last_line = y + 1 >= y_limit;
         const bool add_trailing_newline = insert_newlines && !is_last_line;
         PyObject *text = NULL;
-        if (x_limit <= x_start && is_only_whitespace_line) {  // we want a newline on only whitespace lines even if they are continued
+        if (x_limit <= x_start && (is_only_whitespace_line || line_is_empty(line))) {
+            // we want a newline on only whitespace lines even if they are continued
             text = add_trailing_newline ? nl : empty;
             text = Py_NewRef(text);
         } else {
@@ -3627,7 +3628,8 @@ ansi_for_range(Screen *self, const Selection *sel, bool insert_newlines, bool st
             }
         }
 
-        if (x_limit <= x_start && is_only_whitespace_line) {  // we want a newline on only whitespace lines even if they are continued
+        if (x_limit <= x_start && (is_only_whitespace_line || line_is_empty(line))) {
+            // we want a newline on only whitespace lines even if they are continued
             if (insert_newlines) need_newline = true;
         } else {
             char_type prefix_char = need_newline ? '\n' : 0;

kitty_tests/mouse.py

@@ -79,8 +79,9 @@ def release(x=0, y=0, button=GLFW_MOUSE_BUTTON_LEFT):
         def move(x=0, y=0, button=-1, q=None):
             ev(x=x, y=y, button=button)
             if q is not None:
-                s = sel()
-                self.ae(s, q, f'{s!r} != {q!r} after movement to x={x} y={y}')
+                sl = sel()
+                from kitty.window import as_text
+                self.ae(sl, q, f'{sl!r} != {q!r} after movement to x={x} y={y}. Screen contents: {as_text(s)!r}')
 
         def multi_click(x=0, y=0, count=2):
             clear_click_queue = True
@@ -277,3 +278,12 @@ def scroll(x=0, y=0, up=True):
         move(x=3.6, y=2, q='abcd')
         press(x=3, y=0, button=GLFW_MOUSE_BUTTON_RIGHT)
         self.ae(sel(), '4567890abcd')
+
+        # blank line select
+        s.reset()
+        s.draw('abcde')
+        s.linefeed(), s.carriage_return()
+        s.linefeed(), s.carriage_return()
+        s.draw('12345')
+        press(x=0, y=0)
+        move(x=2, y=2, q='abcde\n\n12')