refactor(plines): move out plines related code from misc1.c

1 files changed, 197 insertions, 0 deletions

diff --git a/src/nvim/plines.c b/src/nvim/plines.c
new file mode 100644
index 0000000000..c88d584f64
--- /dev/null
+++ b/src/nvim/plines.c
@@ -0,0 +1,197 @@
+// This is an open source non-commercial project. Dear PVS-Studio, please check
+// it. PVS-Studio Static Code Analyzer for C, C++ and C#: http://www.viva64.com
+
+// plines.c: functions that calculate the vertical and horizontal size of text
+
+#include <assert.h>
+#include <inttypes.h>
+#include <stdbool.h>
+#include <string.h>
+#include <limits.h>
+
+#include "nvim/vim.h"
+#include "nvim/ascii.h"
+#include "nvim/plines.h"
+#include "nvim/charset.h"
+#include "nvim/cursor.h"
+#include "nvim/diff.h"
+#include "nvim/func_attr.h"
+#include "nvim/fold.h"
+#include "nvim/main.h"
+#include "nvim/mbyte.h"
+#include "nvim/memline.h"
+#include "nvim/memory.h"
+#include "nvim/move.h"
+#include "nvim/option.h"
+#include "nvim/screen.h"
+#include "nvim/strings.h"
+#include "nvim/window.h"
+#include "nvim/buffer.h"
+
+#ifdef INCLUDE_GENERATED_DECLARATIONS
+# include "plines.c.generated.h"
+#endif
+
+int plines_win(
+    win_T *const wp,
+    const linenr_T lnum,
+    const bool winheight          // when true limit to window height
+)
+{
+  /* Check for filler lines above this buffer line.  When folded the result
+   * is one line anyway. */
+  return plines_win_nofill(wp, lnum, winheight) + diff_check_fill(wp, lnum);
+}
+
+int plines_nofill(const linenr_T lnum)
+{
+  return plines_win_nofill(curwin, lnum, true);
+}
+
+int plines_win_nofill(
+    win_T *const wp,
+    const linenr_T lnum,
+    const bool winheight          // when true limit to window height
+)
+{
+  if (!wp->w_p_wrap) {
+    return 1;
+  }
+
+  if (wp->w_width_inner == 0) {
+    return 1;
+  }
+
+  // A folded lines is handled just like an empty line.
+  if (lineFolded(wp, lnum)) {
+    return 1;
+  }
+
+  const int lines = plines_win_nofold(wp, lnum);
+  if (winheight && lines > wp->w_height_inner) {
+    return wp->w_height_inner;
+  }
+  return lines;
+}
+
+/*
+ * Return number of window lines physical line "lnum" will occupy in window
+ * "wp".  Does not care about folding, 'wrap' or 'diff'.
+ */
+int plines_win_nofold(win_T *wp, linenr_T lnum)
+{
+  char_u      *s;
+  unsigned int col;
+  int width;
+
+  s = ml_get_buf(wp->w_buffer, lnum, FALSE);
+  if (*s == NUL)                /* empty line */
+    return 1;
+  col = win_linetabsize(wp, s, MAXCOL);
+
+  // If list mode is on, then the '$' at the end of the line may take up one
+  // extra column.
+  if (wp->w_p_list && wp->w_p_lcs_chars.eol != NUL) {
+    col += 1;
+  }
+
+  /*
+   * Add column offset for 'number', 'relativenumber' and 'foldcolumn'.
+   */
+  width = wp->w_width_inner - win_col_off(wp);
+  if (width <= 0 || col > 32000) {
+    return 32000;  // bigger than the number of screen columns
+  }
+  if (col <= (unsigned int)width) {
+    return 1;
+  }
+  col -= (unsigned int)width;
+  width += win_col_off2(wp);
+  assert(col <= INT_MAX && (int)col < INT_MAX - (width -1));
+  return ((int)col + (width - 1)) / width + 1;
+}
+
+/*
+ * Like plines_win(), but only reports the number of physical screen lines
+ * used from the start of the line to the given column number.
+ */
+int plines_win_col(win_T *wp, linenr_T lnum, long column)
+{
+  // Check for filler lines above this buffer line.  When folded the result
+  // is one line anyway.
+  int lines = diff_check_fill(wp, lnum);
+
+  if (!wp->w_p_wrap)
+    return lines + 1;
+
+  if (wp->w_width_inner == 0) {
+    return lines + 1;
+  }
+
+  char_u *line = ml_get_buf(wp->w_buffer, lnum, false);
+  char_u *s = line;
+
+  colnr_T col = 0;
+  while (*s != NUL && --column >= 0) {
+    col += win_lbr_chartabsize(wp, line, s, col, NULL);
+    MB_PTR_ADV(s);
+  }
+
+  // If *s is a TAB, and the TAB is not displayed as ^I, and we're not in
+  // INSERT mode, then col must be adjusted so that it represents the last
+  // screen position of the TAB.  This only fixes an error when the TAB wraps
+  // from one screen line to the next (when 'columns' is not a multiple of
+  // 'ts') -- webb.
+  if (*s == TAB && (State & NORMAL)
+      && (!wp->w_p_list || wp->w_p_lcs_chars.tab1)) {
+    col += win_lbr_chartabsize(wp, line, s, col, NULL) - 1;
+  }
+
+  // Add column offset for 'number', 'relativenumber', 'foldcolumn', etc.
+  int width = wp->w_width_inner - win_col_off(wp);
+  if (width <= 0) {
+    return 9999;
+  }
+
+  lines += 1;
+  if (col > width)
+    lines += (col - width) / (width + win_col_off2(wp)) + 1;
+  return lines;
+}
+
+/// Get the number of screen lines lnum takes up. This takes care of
+/// both folds and topfill, and limits to the current window height.
+///
+/// @param[in]  wp       window line is in
+/// @param[in]  lnum     line number
+/// @param[out] nextp    if not NULL, the line after a fold
+/// @param[out] foldedp  if not NULL, whether lnum is on a fold
+/// @param[in]  cache    whether to use the window's cache for folds
+///
+/// @return the total number of screen lines
+int plines_win_full(win_T *wp, linenr_T lnum, linenr_T *const nextp,
+                    bool *const foldedp, const bool cache)
+{
+  bool folded = hasFoldingWin(wp, lnum, NULL, nextp, cache, NULL);
+  if (foldedp) {
+    *foldedp = folded;
+  }
+  if (folded) {
+    return 1;
+  } else if (lnum == wp->w_topline) {
+    return plines_win_nofill(wp, lnum, true) + wp->w_topfill;
+  }
+  return plines_win(wp, lnum, true);
+}
+
+int plines_m_win(win_T *wp, linenr_T first, linenr_T last)
+{
+  int count = 0;
+
+  while (first <= last) {
+    linenr_T next = first;
+    count += plines_win_full(wp, first, &next, NULL, false);
+    first = next + 1;
+  }
+  return count;
+}