patch 9.1.0441: getregionpos() can't properly indicate positions beyond eolv9.1.0441

Problem:  getregionpos() can't properly indicate positions beyond eol.
Solution: Add an "eol" flag that enables handling positions beyond end
          of line like getpos() does (zeertzjq).

Also fix the problem that a position still has the coladd beyond the end
of the line when its column has been clamped.  In the last test case
with TABs at the end of the line the old behavior is obviously wrong.

I decided to gate this behind a flag because returning positions that
don't correspond to actual characters in the line may lead to mistakes
for callers that want to calculate the length of the selected text, so
the behavior is only enabled if the caller wants it.

closes: #14838

Signed-off-by: zeertzjq <zeertzjq@outlook.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>

1 files changed, 32 insertions, 7 deletions

diff --git a/src/evalfunc.c b/src/evalfunc.c
index f70b032ad2..a1f8a8f8e2 100644
--- a/src/evalfunc.c
+++ b/src/evalfunc.c
@@ -5695,7 +5695,6 @@ f_getregion(typval_T *argvars, typval_T *rettv)
 add_regionpos_range(typval_T *rettv, pos_T p1, pos_T p2)
 {
     list_T	*l1, *l2, *l3;
-    int		max_col1, max_col2;
 
     l1 = list_alloc();
     if (l1 == NULL)
@@ -5737,16 +5736,14 @@ add_regionpos_range(typval_T *rettv, pos_T p1, pos_T p2)
 	return;
     }
 
-    max_col1 = ml_get_len(p1.lnum);
     list_append_number(l2, curbuf->b_fnum);
     list_append_number(l2, p1.lnum);
-    list_append_number(l2, p1.col > max_col1 ? max_col1 : p1.col);
+    list_append_number(l2, p1.col);
     list_append_number(l2, p1.coladd);
 
-    max_col2 = ml_get_len(p2.lnum);
     list_append_number(l3, curbuf->b_fnum);
     list_append_number(l3, p2.lnum);
-    list_append_number(l3, p2.col > max_col2 ? max_col2 : p2.col);
+    list_append_number(l3, p2.col);
     list_append_number(l3, p2.coladd);
 }
 
@@ -5759,6 +5756,7 @@ f_getregionpos(typval_T *argvars, typval_T *rettv)
     pos_T	p1, p2;
     int		inclusive = TRUE;
     int		region_type = -1;
+    int		allow_eol = FALSE;
     oparg_T	oa;
     int		lnum;
 
@@ -5772,9 +5770,13 @@ f_getregionpos(typval_T *argvars, typval_T *rettv)
 		&p1, &p2, &inclusive, &region_type, &oa) == FAIL)
 	return;
 
+    if (argvars[2].v_type == VAR_DICT)
+	allow_eol = dict_get_bool(argvars[2].vval.v_dict, "eol", FALSE);
+
     for (lnum = p1.lnum; lnum <= p2.lnum; lnum++)
     {
-	pos_T			ret_p1, ret_p2;
+	pos_T		ret_p1, ret_p2;
+	colnr_T		line_len = ml_get_len(lnum);
 
 	if (region_type == MLINE)
 	{
@@ -5806,6 +5808,13 @@ f_getregionpos(typval_T *argvars, typval_T *rettv)
 		    ret_p1.coladd = p1.coladd;
 		}
 	    }
+	    else if (region_type == MBLOCK && oa.start_vcol > bd.start_vcol)
+	    {
+		// blockwise selection entirely beyond end of line
+		ret_p1.col = MAXCOL;
+		ret_p1.coladd = oa.start_vcol - bd.start_vcol;
+		bd.is_oneChar = TRUE;
+	    }
 	    else if (bd.startspaces > 0)
 	    {
 		ret_p1.col = bd.textcol;
@@ -5820,7 +5829,7 @@ f_getregionpos(typval_T *argvars, typval_T *rettv)
 	    if (bd.is_oneChar)  // selection entirely inside one char
 	    {
 		ret_p2.col = ret_p1.col;
-		ret_p2.coladd = ret_p1.coladd + bd.startspaces;
+		ret_p2.coladd = ret_p1.coladd + bd.startspaces + bd.endspaces;
 	    }
 	    else if (bd.endspaces > 0)
 	    {
@@ -5834,6 +5843,22 @@ f_getregionpos(typval_T *argvars, typval_T *rettv)
 	    }
 	}
 
+	if (!allow_eol && ret_p1.col > line_len)
+	{
+	    ret_p1.col = 0;
+	    ret_p1.coladd = 0;
+	}
+	else if (ret_p1.col > line_len + 1)
+	    ret_p1.col = line_len + 1;
+
+	if (!allow_eol && ret_p2.col > line_len)
+	{
+	    ret_p2.col = ret_p1.col == 0 ? 0 : line_len;
+	    ret_p2.coladd = 0;
+	}
+	else if (ret_p2.col > line_len + 1)
+	    ret_p2.col = line_len + 1;
+
 	ret_p1.lnum = lnum;
 	ret_p2.lnum = lnum;
 	add_regionpos_range(rettv, ret_p1, ret_p2);