patch 8.2.1183: assert_fails() checks the last error message
Problem: assert_fails() checks the last error message.
Solution: Check the first error, it is more relevant. Fix all the tests
that rely on the old behavior.
diff --git a/src/testdir/test_python2.vim b/src/testdir/test_python2.vim
index 42fadaa..8fa7340 100644
--- a/src/testdir/test_python2.vim
+++ b/src/testdir/test_python2.vim
@@ -73,7 +73,7 @@
" Try modifying a buffer with 'nomodifiable' set
set nomodifiable
- call assert_fails('pydo toupper(line)', 'cannot save undo information')
+ call assert_fails('pydo toupper(line)', 'E21:')
set modifiable
" Invalid command