view: fix screen line based motions when cursor is not visible

If a cursor is not currently visible it has no associated screen line.
Fallback to the corresponding logical line based variant. For example
`gj` is interpreted as `j`.

Fixes #354

1 files changed, 4 insertions, 0 deletions

diff --git a/view.c b/view.c
index 33e73cd..2d4730d 100644
--- a/view.c
+++ b/view.c
@@ -772,6 +772,8 @@ size_t view_line_down(Cursor *cursor) {
 }
 
 size_t view_screenline_up(Cursor *cursor) {
+	if (!cursor->line)
+		return view_line_up(cursor);
 	int lastcol = cursor->lastcol;
 	if (!lastcol)
 		lastcol = cursor->col;
@@ -784,6 +786,8 @@ size_t view_screenline_up(Cursor *cursor) {
 }
 
 size_t view_screenline_down(Cursor *cursor) {
+	if (!cursor->line)
+		return view_line_down(cursor);
 	int lastcol = cursor->lastcol;
 	if (!lastcol)
 		lastcol = cursor->col;