feat: show absolute line number on cursor in relative mode

core/editor/editor.cpp

@@ -144,6 +144,7 @@ i32 EditorGutterWidth(Editor *ed, const Panel *panel) {
 u64 EditorLineNumberLabel(const Editor *ed, const View *view, const Buffer *buffer, u64 line) {
   if (ed && ed->line_number_mode == LineNumberMode::Relative) {
     u64 cursor_line = ViewCursorLine(view, buffer);
+    if (line == cursor_line) return line + 1;
     return (line > cursor_line) ? line - cursor_line : cursor_line - line;
   }
   return line + 1;  // buffer lines are 0-based; the display is not

core/editor/editor.h

@@ -16,8 +16,8 @@
 inline constexpr u64 kMaxRecordedChords = 128;
 
 // What the gutter counts. Relative shows each line's distance from the cursor,
-// with 0 on the cursor's own line, which is what makes a jump count something
-// you read rather than work out.
+// with the absolute 1-based number on the cursor's own line (vim's number +
+// relativenumber), so a jump count is something you read rather than work out.
 //
 // There is no config file, so this is a source-level setting: change
 // kLineNumberModeDefault and rebuild. :number, :relativenumber and :nonumber
@@ -220,8 +220,8 @@ void EditorSetScreen(Editor *ed, RectS32 screen);
 // plus one blank column separating the numbers from the text.
 [[nodiscard]] i32 EditorGutterWidth(Editor *ed, const Panel *panel);
 
-// The number `line` displays: its distance from the cursor when relative (0 on
-// the cursor's own line), otherwise the 1-based line number.
+// The number `line` displays: its distance from the cursor when relative, or
+// the 1-based line number on the cursor's own line / in absolute mode.
 [[nodiscard]] u64 EditorLineNumberLabel(const Editor *ed, const View *view,
                                         const Buffer *buffer, u64 line);
 

docs/rendering.md

@@ -4,9 +4,10 @@ Fonts are chosen at runtime. Colours are compiled in.
 
 ## Line numbers
 
-The gutter shows each line's distance from the cursor, with `0` on the cursor's
-own line — vim's `relativenumber`. `:number` switches to absolute numbers,
-`:relativenumber` back, and `:nonumber` hides the gutter entirely.
+The gutter shows each line's distance from the cursor, with the absolute
+1-based number on the cursor's own line — vim's `number` + `relativenumber`.
+`:number` switches to absolute numbers, `:relativenumber` back, and
+`:nonumber` hides the gutter entirely.
 
 To change what it starts as, edit one constant in `core/editor/editor.h`:
 

tests/test_vim.cpp

@@ -1598,8 +1598,8 @@ TEST(line_numbers_relative_labels_count_from_the_cursor) {
   Type(&f, "2j");
   CHECK_EQ(CursorLine(&f), 2);
 
-  // Zero on the cursor's own line, distances either side of it.
-  CHECK_EQ(EditorLineNumberLabel(&f.ed, view, buffer, 2), 0);
+  // Absolute number on the cursor's own line, distances either side of it.
+  CHECK_EQ(EditorLineNumberLabel(&f.ed, view, buffer, 2), 3);
   CHECK_EQ(EditorLineNumberLabel(&f.ed, view, buffer, 1), 1);
   CHECK_EQ(EditorLineNumberLabel(&f.ed, view, buffer, 0), 2);
   CHECK_EQ(EditorLineNumberLabel(&f.ed, view, buffer, 3), 1);
@@ -1608,7 +1608,7 @@ TEST(line_numbers_relative_labels_count_from_the_cursor) {
   // They follow the cursor rather than being computed once.
   Type(&f, "j");
   CHECK_EQ(EditorLineNumberLabel(&f.ed, view, buffer, 2), 1);
-  CHECK_EQ(EditorLineNumberLabel(&f.ed, view, buffer, 3), 0);
+  CHECK_EQ(EditorLineNumberLabel(&f.ed, view, buffer, 3), 4);
 
   Destroy(&f);
 }