feat(api)!: change return type of nvim_win_text_height to Dict (#24365)

3 files changed, 55 insertions, 37 deletions

diff --git a/src/nvim/api/window.c b/src/nvim/api/window.c
index 07aad2cd88..5480584aa5 100644
--- a/src/nvim/api/window.c
+++ b/src/nvim/api/window.c
@@ -488,15 +488,20 @@ void nvim_win_set_hl_ns(Window window, Integer ns_id, Error *err)
 ///                - end_vcol: Ending virtual column index on "end_row",
 ///                            0-based exclusive, rounded up to full screen lines.
 ///                            When omitted include the whole line.
-/// @return  The number of screen lines that the range of text occupy.
+/// @return  Dictionary containing text height information, with these keys:
+///          - all: The total number of screen lines occupied by the range.
+///          - fill: The number of diff filler or virtual lines among them.
 ///
 /// @see |virtcol()| for text width.
-Object nvim_win_text_height(Window window, Dict(win_text_height) *opts, Error *err)
+Dictionary nvim_win_text_height(Window window, Dict(win_text_height) *opts, Arena *arena,
+                                Error *err)
   FUNC_API_SINCE(12)
 {
+  Dictionary rv = arena_dict(arena, 2);
+
   win_T *const win = find_window_by_handle(window, err);
   if (!win) {
-    return NIL;
+    return rv;
   }
   buf_T *const buf = win->w_buffer;
   const linenr_T line_count = buf->b_ml.ml_line_count;
@@ -510,58 +515,65 @@ Object nvim_win_text_height(Window window, Dict(win_text_height) *opts, Error *e
 
   if (HAS_KEY(opts->start_row)) {
     VALIDATE_T("start_row", kObjectTypeInteger, opts->start_row.type, {
-      return NIL;
+      return rv;
     });
     start_lnum = (linenr_T)normalize_index(buf, opts->start_row.data.integer, false, &oob);
   }
 
   if (HAS_KEY(opts->end_row)) {
     VALIDATE_T("end_row", kObjectTypeInteger, opts->end_row.type, {
-      return NIL;
+      return rv;
     });
     end_lnum = (linenr_T)normalize_index(buf, opts->end_row.data.integer, false, &oob);
   }
 
   VALIDATE(!oob, "%s", "Line index out of bounds", {
-    return NIL;
+    return rv;
   });
   VALIDATE((start_lnum <= end_lnum), "%s", "'start_row' is higher than 'end_row'", {
-    return NIL;
+    return rv;
   });
 
   if (HAS_KEY(opts->start_vcol)) {
     VALIDATE(HAS_KEY(opts->start_row), "%s", "'start_vcol' specified without 'start_row'", {
-      return NIL;
+      return rv;
     });
     VALIDATE_T("start_vcol", kObjectTypeInteger, opts->start_vcol.type, {
-      return NIL;
+      return rv;
     });
     start_vcol = opts->start_vcol.data.integer;
     VALIDATE_RANGE((start_vcol >= 0 && start_vcol <= MAXCOL), "start_vcol", {
-      return NIL;
+      return rv;
     });
   }
 
   if (HAS_KEY(opts->end_vcol)) {
     VALIDATE(HAS_KEY(opts->end_row), "%s", "'end_vcol' specified without 'end_row'", {
-      return NIL;
+      return rv;
     });
     VALIDATE_T("end_vcol", kObjectTypeInteger, opts->end_vcol.type, {
-      return NIL;
+      return rv;
     });
     end_vcol = opts->end_vcol.data.integer;
     VALIDATE_RANGE((end_vcol >= 0 && end_vcol <= MAXCOL), "end_vcol", {
-      return NIL;
+      return rv;
     });
   }
 
   if (start_lnum == end_lnum && start_vcol >= 0 && end_vcol >= 0) {
     VALIDATE((start_vcol <= end_vcol), "%s", "'start_vcol' is higher than 'end_vcol'", {
-      return NIL;
+      return rv;
     });
   }
 
-  const int64_t res = win_text_height(win, start_lnum, start_vcol, end_lnum, end_vcol)
-                      + (HAS_KEY(opts->end_row) ? 0 : win_get_fill(win, line_count + 1));
-  return INTEGER_OBJ(res);
+  int64_t fill = 0;
+  int64_t all = win_text_height(win, start_lnum, start_vcol, end_lnum, end_vcol, &fill);
+  if (!HAS_KEY(opts->end_row)) {
+    const int64_t end_fill = win_get_fill(win, line_count + 1);
+    fill += end_fill;
+    all += end_fill;
+  }
+  PUT_C(rv, "all", INTEGER_OBJ(all));
+  PUT_C(rv, "fill", INTEGER_OBJ(fill));
+  return rv;
 }
diff --git a/src/nvim/plines.c b/src/nvim/plines.c
index 73b15edb27..236a992bf9 100644
--- a/src/nvim/plines.c
+++ b/src/nvim/plines.c
@@ -600,16 +600,17 @@ static int win_nolbr_chartabsize(chartabsize_T *cts, int *headp)
 
 /// Get the number of screen lines a range of text will take in window "wp".
 ///
-/// @param start_lnum  Starting line number, 1-based inclusive.
-/// @param start_vcol  >= 0: Starting virtual column index on "start_lnum",
-///                          0-based inclusive, rounded down to full screen lines.
-///                    < 0:  Count a full "start_lnum", including filler lines above.
-/// @param end_lnum    Ending line number, 1-based inclusive.
-/// @param end_vcol    >= 0: Ending virtual column index on "end_lnum",
-///                          0-based exclusive, rounded up to full screen lines.
-///                    < 0:  Count a full "end_lnum", not including fillers lines below.
+/// @param[in] start_lnum  Starting line number, 1-based inclusive.
+/// @param[in] start_vcol  >= 0: Starting virtual column index on "start_lnum",
+///                              0-based inclusive, rounded down to full screen lines.
+///                        < 0:  Count a full "start_lnum", including filler lines above.
+/// @param[in] end_lnum    Ending line number, 1-based inclusive.
+/// @param[in] end_vcol    >= 0: Ending virtual column index on "end_lnum",
+///                              0-based exclusive, rounded up to full screen lines.
+///                        < 0:  Count a full "end_lnum", not including filler lines below.
+/// @param[out] fill       If not NULL, set to the number of filler lines in the range.
 int64_t win_text_height(win_T *const wp, const linenr_T start_lnum, const int64_t start_vcol,
-                        const linenr_T end_lnum, const int64_t end_vcol)
+                        const linenr_T end_lnum, const int64_t end_vcol, int64_t *const fill)
 {
   int width1 = 0;
   int width2 = 0;
@@ -620,39 +621,44 @@ int64_t win_text_height(win_T *const wp, const linenr_T start_lnum, const int64_
     width2 = MAX(width2, 0);
   }
 
-  int64_t height_sum = 0;
+  int64_t height_sum_fill = 0;
   int64_t height_cur_nofill = 0;
+  int64_t height_sum_nofill = 0;
   linenr_T lnum = start_lnum;
 
   if (start_vcol >= 0) {
     linenr_T lnum_next = lnum;
     const bool folded = hasFoldingWin(wp, lnum, &lnum, &lnum_next, true, NULL);
     height_cur_nofill = folded ? 1 : plines_win_nofill(wp, lnum, false);
-    height_sum += height_cur_nofill;
+    height_sum_nofill += height_cur_nofill;
     const int64_t row_off = (start_vcol < width1 || width2 <= 0)
                             ? 0
                             : 1 + (start_vcol - width1) / width2;
-    height_sum -= MIN(row_off, height_cur_nofill);
+    height_sum_nofill -= MIN(row_off, height_cur_nofill);
     lnum = lnum_next + 1;
   }
 
   while (lnum <= end_lnum) {
     linenr_T lnum_next = lnum;
     const bool folded = hasFoldingWin(wp, lnum, &lnum, &lnum_next, true, NULL);
+    height_sum_fill += win_get_fill(wp, lnum);
     height_cur_nofill = folded ? 1 : plines_win_nofill(wp, lnum, false);
-    height_sum += win_get_fill(wp, lnum) + height_cur_nofill;
+    height_sum_nofill += height_cur_nofill;
     lnum = lnum_next + 1;
   }
 
   if (end_vcol >= 0) {
-    height_sum -= height_cur_nofill;
+    height_sum_nofill -= height_cur_nofill;
     const int64_t row_off = end_vcol == 0
                             ? 0
                             : (end_vcol <= width1 || width2 <= 0)
                               ? 1
                               : 1 + (end_vcol - width1 + width2 - 1) / width2;
-    height_sum += MIN(row_off, height_cur_nofill);
+    height_sum_nofill += MIN(row_off, height_cur_nofill);
   }
 
-  return height_sum;
+  if (fill != NULL) {
+    *fill = height_sum_fill;
+  }
+  return height_sum_fill + height_sum_nofill;
 }
diff --git a/src/nvim/window.c b/src/nvim/window.c
index 1a78918b09..e230bde95c 100644
--- a/src/nvim/window.c
+++ b/src/nvim/window.c
@@ -1052,19 +1052,19 @@ void ui_ext_win_viewport(win_T *wp)
         || (cur_topline == last_topline && wp->w_skipcol < last_skipcol)) {
       if (last_topline > 0 && cur_botline < last_topline) {
         // Scrolling too many lines: only give an approximate "scroll_delta".
-        delta -= win_text_height(wp, cur_topline, wp->w_skipcol, cur_botline, 0);
+        delta -= win_text_height(wp, cur_topline, wp->w_skipcol, cur_botline, 0, NULL);
         delta -= last_topline - cur_botline;
       } else {
-        delta -= win_text_height(wp, cur_topline, wp->w_skipcol, last_topline, last_skipcol);
+        delta -= win_text_height(wp, cur_topline, wp->w_skipcol, last_topline, last_skipcol, NULL);
       }
     } else if (cur_topline > last_topline
                || (cur_topline == last_topline && wp->w_skipcol > last_skipcol)) {
       if (last_botline > 0 && cur_topline > last_botline) {
         // Scrolling too many lines: only give an approximate "scroll_delta".
-        delta += win_text_height(wp, last_topline, last_skipcol, last_botline, 0);
+        delta += win_text_height(wp, last_topline, last_skipcol, last_botline, 0, NULL);
         delta += cur_topline - last_botline;
       } else {
-        delta += win_text_height(wp, last_topline, last_skipcol, cur_topline, wp->w_skipcol);
+        delta += win_text_height(wp, last_topline, last_skipcol, cur_topline, wp->w_skipcol, NULL);
       }
     }
     delta += last_topfill;