patch 8.0.0542: getpos() can return a negative line number
Problem: getpos() can return a negative line number. (haya14busa)
Solution: Handle a zero topline and botline. (closes #1613)
diff --git a/runtime/doc/eval.txt b/runtime/doc/eval.txt
index 0eccd61..6c3c0da 100644
--- a/runtime/doc/eval.txt
+++ b/runtime/doc/eval.txt
@@ -5413,8 +5413,10 @@
$ the last line in the current buffer
'x position of mark x (if the mark is not set, 0 is
returned)
- w0 first line visible in current window
- w$ last line visible in current window
+ w0 first line visible in current window (one if the
+ display isn't updated, e.g. in silent Ex mode)
+ w$ last line visible in current window (this is one
+ less than "w0" if no lines are visible)
v In Visual mode: the start of the Visual area (the
cursor is the end). When not in Visual mode
returns the cursor position. Differs from |'<| in