commit 5a6ec10cc80ab02eeff644ab19b82312630ea855
author Bram Moolenaar <Bram@vim.org> Fri May 27 21:58:00 2022 +0100
committer Bram Moolenaar <Bram@vim.org> Fri May 27 21:58:00 2022 +0100
tree 5014800ed4c174f1abe451009e6d3ab86261a698
parent 968443efb5a2a1ed7e1084f2aff65a95f2d0a17b

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

Problem:    There is no way to get the byte index from a virtual column.
Solution:   Add virtcol2col(). (Yegappan Lakshmanan, closes #10477,
            closes #10098)

src/evalfunc.c

diff --git a/src/evalfunc.c b/src/evalfunc.c
index a5300a1..75c3456 100644
--- a/src/evalfunc.c
+++ b/src/evalfunc.c
@@ -2682,6 +2682,8 @@
 			ret_list_any,	    f_values},
     {"virtcol",		1, 2, FEARG_1,	    arg2_string_or_list_bool,
 			ret_virtcol,	    f_virtcol},
+    {"virtcol2col",	3, 3, FEARG_1,	    arg3_number,
+			ret_number,	    f_virtcol2col},
     {"visualmode",	0, 1, 0,	    arg1_bool,
 			ret_string,	    f_visualmode},
     {"wildmenumode",	0, 0, 0,	    NULL,

src/move.c

diff --git a/src/move.c b/src/move.c
index 58bd97f..5c78d6c 100644
--- a/src/move.c
+++ b/src/move.c
@@ -1322,6 +1322,39 @@
     dict_add_number(dict, "curscol", ccol);
     dict_add_number(dict, "endcol", ecol);
 }
+
+/*
+ * "virtcol2col({winid}, {lnum}, {col})" function
+ */
+    void
+f_virtcol2col(typval_T *argvars UNUSED, typval_T *rettv)
+{
+    win_T	*wp;
+    linenr_T	lnum;
+    int		screencol;
+    int		error = FALSE;
+
+    rettv->vval.v_number = -1;
+
+    if (check_for_number_arg(argvars, 0) == FAIL
+	    || check_for_number_arg(argvars, 1) == FAIL
+	    || check_for_number_arg(argvars, 2) == FAIL)
+	return;
+
+    wp = find_win_by_nr_or_id(&argvars[0]);
+    if (wp == NULL)
+	return;
+
+    lnum = tv_get_number_chk(&argvars[1], &error);
+    if (error || lnum < 0 || lnum > wp->w_buffer->b_ml.ml_line_count)
+	return;
+
+    screencol = tv_get_number_chk(&argvars[2], &error);
+    if (error || screencol < 0)
+	return;
+
+    rettv->vval.v_number = vcol2col(wp, lnum, screencol);
+}
 #endif
 
 /*

src/proto/move.pro

diff --git a/src/proto/move.pro b/src/proto/move.pro
index e6a0601..3dd6ec1 100644
--- a/src/proto/move.pro
+++ b/src/proto/move.pro
@@ -30,6 +30,7 @@
 void curs_columns(int may_scroll);
 void textpos2screenpos(win_T *wp, pos_T *pos, int *rowp, int *scolp, int *ccolp, int *ecolp);
 void f_screenpos(typval_T *argvars, typval_T *rettv);
+void f_virtcol2col(typval_T *argvars, typval_T *rettv);
 void scrolldown(long line_count, int byfold);
 void scrollup(long line_count, int byfold);
 void check_topfill(win_T *wp, int down);

src/testdir/test_cursor_func.vim

diff --git a/src/testdir/test_cursor_func.vim b/src/testdir/test_cursor_func.vim
index 1c26f6d..d5f0ac7 100644
--- a/src/testdir/test_cursor_func.vim
+++ b/src/testdir/test_cursor_func.vim
@@ -419,4 +419,26 @@
   %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

src/version.c

diff --git a/src/version.c b/src/version.c
index 0d666a0..adfd87b 100644
--- a/src/version.c
+++ b/src/version.c
@@ -735,6 +735,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    5034,
+/**/
     5033,
 /**/
     5032,