Merge pull request #20163 from zeertzjq/vim-8.2.5034

vim-patch:8.2.5034: there is no way to get the byte index from a virtual column

runtime/doc/builtin.txt

@@ -526,6 +526,8 @@ uniq({list} [, {func} [, {dict}]])
 				List	remove adjacent duplicates from a list
 values({dict})			List	values in {dict}
 virtcol({expr})			Number	screen column of cursor or mark
+virtcol2col({winid}, {lnum}, {col})
+				Number  byte index of a character on screen
 visualmode([expr])		String	last visual mode used
 wait({timeout}, {condition} [, {interval}])
 				Number	Wait until {condition} is satisfied
@@ -5620,12 +5622,19 @@ nvim_...({...})					*E5555* *nvim_...()* *eval-api*
 or({expr}, {expr})					*or()*
 		Bitwise OR on the two arguments.  The arguments are converted
 		to a number.  A List, Dict or Float argument causes an error.
+		Also see `and()` and `xor()`.
 		Example: >
 			:let bits = or(bits, 0x80)
 <		Can also be used as a |method|: >
 			:let bits = bits->or(0x80)
 
-pathshorten({expr} [, {len}])				*pathshorten()*
+<		Rationale: The reason this is a function and not using the "|"
+		character like many languages, is that Vi has always used "|"
+		to separate commands.  In many places it would not be clear if
+		"|" is an operator or a command separator.
+
+
+pathshorten({path} [, {len}])				*pathshorten()*
 		Shorten directory names in the path {path} and return the
 		result.  The tail, the file name, is kept as-is.  The other
 		components in the path are reduced to {len} letters in length.
@@ -8831,6 +8840,26 @@ virtcol({expr})						*virtcol()*
 <		Can also be used as a |method|: >
 			GetPos()->virtcol()
 
+virtcol2col({winid}, {lnum}, {col})			*virtcol2col()*
+		The result is a Number, which is the byte index of the
+		character in window {winid} at buffer line {lnum} and virtual
+		column {col}.
+
+		If {col} is greater than the last virtual column in line
+		{lnum}, then the byte index of the character at the last
+		virtual column is returned.
+
+		The {winid} argument can be the window number or the
+		|window-ID|. If this is zero, then the current window is used.
+
+		Returns -1 if the window {winid} doesn't exist or the buffer
+		line {lnum} or virtual column {col} is invalid.
+
+		See also |screenpos()|, |virtcol()| and |col()|.
+
+		Can also be used as a |method|: >
+			GetWinid()->virtcol2col(lnum, col)
+
 visualmode([{expr}])						*visualmode()*
 		The result is a String, which describes the last Visual mode
 		used in the current buffer.  Initially it returns an empty
@@ -9262,6 +9291,7 @@ writefile({object}, {fname} [, {flags}])
 xor({expr}, {expr})					*xor()*
 		Bitwise XOR on the two arguments.  The arguments are converted
 		to a number.  A List, Dict or Float argument causes an error.
+		Also see `and()` and `or()`.
 		Example: >
 			:let bits = xor(bits, 0x80)
 <

runtime/doc/usr_41.txt

@@ -745,6 +745,7 @@ Cursor and mark position:		*cursor-functions* *mark-functions*
 	screencol()		get screen column of the cursor
 	screenrow()		get screen row of the cursor
 	screenpos()		screen row and col of a text character
+	virtcol2col()		byte index of a text character on screen
 	getcurpos()		get position of the cursor
 	getpos()		get position of cursor, mark, etc.
 	setpos()		set position of cursor, mark, etc.

src/nvim/eval.lua

@@ -425,6 +425,7 @@ return {
     uniq={args={1, 3}, base=1},
     values={args=1, base=1},
     virtcol={args=1, base=1},
+    virtcol2col={args=3, base=1},
     visualmode={args={0, 1}},
     wait={args={2,3}},
     wildmenumode={},

src/nvim/eval/funcs.c

@@ -7057,32 +7057,6 @@ static void f_screencol(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
   rettv->vval.v_number = ui_current_col() + 1;
 }
 
-/// "screenpos({winid}, {lnum}, {col})" function
-static void f_screenpos(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
-{
-  tv_dict_alloc_ret(rettv);
-  dict_T *dict = rettv->vval.v_dict;
-
-  win_T *wp = find_win_by_nr_or_id(&argvars[0]);
-  if (wp == NULL) {
-    return;
-  }
-
-  pos_T pos = {
-    .lnum   = (linenr_T)tv_get_number(&argvars[1]),
-    .col    = (colnr_T)tv_get_number(&argvars[2]) - 1,
-    .coladd = 0
-  };
-  int row = 0;
-  int scol = 0, ccol = 0, ecol = 0;
-  textpos2screenpos(wp, &pos, &row, &scol, &ccol, &ecol, false);
-
-  tv_dict_add_nr(dict, S_LEN("row"), row);
-  tv_dict_add_nr(dict, S_LEN("col"), scol);
-  tv_dict_add_nr(dict, S_LEN("curscol"), ccol);
-  tv_dict_add_nr(dict, S_LEN("endcol"), ecol);
-}
-
 /// "screenrow()" function
 static void f_screenrow(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
 {

src/nvim/eval/typval.c

@@ -44,6 +44,8 @@ static char e_string_required_for_argument_nr[]
   = N_("E1174: String required for argument %d");
 static char e_non_empty_string_required_for_argument_nr[]
   = N_("E1142: Non-empty string required for argument %d");
+static char e_number_required_for_argument_nr[]
+  = N_("E1210: Number required for argument %d");
 
 bool tv_in_free_unref_items = false;
 
@@ -3830,6 +3832,17 @@ int tv_check_for_nonempty_string_arg(const typval_T *const args, const int idx)
   return OK;
 }
 
+/// Give an error and return FAIL unless "args[idx]" is a number.
+int tv_check_for_number_arg(const typval_T *const args, const int idx)
+  FUNC_ATTR_NONNULL_ALL FUNC_ATTR_WARN_UNUSED_RESULT FUNC_ATTR_PURE
+{
+  if (args[idx].v_type != VAR_NUMBER) {
+    semsg(_(e_number_required_for_argument_nr), idx + 1);
+    return FAIL;
+  }
+  return OK;
+}
+
 /// Get the string value of a "stringish" VimL object.
 ///
 /// @param[in]  tv  Object to get value of.

src/nvim/move.c

@@ -21,12 +21,15 @@
 #include "nvim/diff.h"
 #include "nvim/drawscreen.h"
 #include "nvim/edit.h"
+#include "nvim/eval.h"
+#include "nvim/eval/typval.h"
 #include "nvim/fold.h"
 #include "nvim/getchar.h"
 #include "nvim/grid.h"
 #include "nvim/highlight.h"
 #include "nvim/mbyte.h"
 #include "nvim/memline.h"
+#include "nvim/mouse.h"
 #include "nvim/move.h"
 #include "nvim/option.h"
 #include "nvim/plines.h"
@@ -977,6 +980,62 @@ void textpos2screenpos(win_T *wp, pos_T *pos, int *rowp, int *scolp, int *ccolp,
   *ecolp = ecol + coloff;
 }
 
+/// "screenpos({winid}, {lnum}, {col})" function
+void f_screenpos(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
+{
+  tv_dict_alloc_ret(rettv);
+  dict_T *dict = rettv->vval.v_dict;
+
+  win_T *wp = find_win_by_nr_or_id(&argvars[0]);
+  if (wp == NULL) {
+    return;
+  }
+
+  pos_T pos = {
+    .lnum   = (linenr_T)tv_get_number(&argvars[1]),
+    .col    = (colnr_T)tv_get_number(&argvars[2]) - 1,
+    .coladd = 0
+  };
+  int row = 0;
+  int scol = 0, ccol = 0, ecol = 0;
+  textpos2screenpos(wp, &pos, &row, &scol, &ccol, &ecol, false);
+
+  tv_dict_add_nr(dict, S_LEN("row"), row);
+  tv_dict_add_nr(dict, S_LEN("col"), scol);
+  tv_dict_add_nr(dict, S_LEN("curscol"), ccol);
+  tv_dict_add_nr(dict, S_LEN("endcol"), ecol);
+}
+
+/// "virtcol2col({winid}, {lnum}, {col})" function
+void f_virtcol2col(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
+{
+  rettv->vval.v_number = -1;
+
+  if (tv_check_for_number_arg(argvars, 0) == FAIL
+      || tv_check_for_number_arg(argvars, 1) == FAIL
+      || tv_check_for_number_arg(argvars, 2) == FAIL) {
+    return;
+  }
+
+  win_T *wp = find_win_by_nr_or_id(&argvars[0]);
+  if (wp == NULL) {
+    return;
+  }
+
+  bool error = false;
+  linenr_T lnum = (linenr_T)tv_get_number_chk(&argvars[1], &error);
+  if (error || lnum < 0 || lnum > wp->w_buffer->b_ml.ml_line_count) {
+    return;
+  }
+
+  int screencol = (int)tv_get_number_chk(&argvars[2], &error);
+  if (error || screencol < 0) {
+    return;
+  }
+
+  rettv->vval.v_number = vcol2col(wp, lnum, screencol);
+}
+
 /// Scroll the current window down by "line_count" logical lines.  "CTRL-Y"
 ///
 /// @param line_count number of lines to scroll

src/nvim/testdir/test_cursor_func.vim

@@ -373,4 +373,26 @@ func Test_setcursorcharpos()
   %bw!
 endfunc
 
+" Test for virtcol2col()
+func Test_virtcol2col()
+  new
+  call setline(1, ["a\tb\tc"])
+  call assert_equal(1, virtcol2col(0, 1, 1))
+  call assert_equal(2, virtcol2col(0, 1, 2))
+  call assert_equal(2, virtcol2col(0, 1, 8))
+  call assert_equal(3, virtcol2col(0, 1, 9))
+  call assert_equal(4, virtcol2col(0, 1, 10))
+  call assert_equal(4, virtcol2col(0, 1, 16))
+  call assert_equal(5, virtcol2col(0, 1, 17))
+  call assert_equal(-1, virtcol2col(10, 1, 1))
+  call assert_equal(-1, virtcol2col(0, 10, 1))
+  call assert_equal(-1, virtcol2col(0, -1, 1))
+  call assert_equal(-1, virtcol2col(0, 1, -1))
+  call assert_equal(5, virtcol2col(0, 1, 20))
+  call assert_fails('echo virtcol2col("0", 1, 20)', 'E1210:')
+  call assert_fails('echo virtcol2col(0, "1", 20)', 'E1210:')
+  call assert_fails('echo virtcol2col(0, 1, "1")', 'E1210:')
+  bw!
+endfunc
+
 " vim: shiftwidth=2 sts=2 expandtab