patch 8.2.2880: unified diff fails if actually used Commit: https://github.com/vim/vim/commit/ad5c178a191cf2cf37a27c2a789d7afda3879831 Author: glacambre <code@lacamb.re> Date: Mon May 24 14:20:53 2021 +0200 patch 8.2.2880: unified diff fails if actually used Problem: Unified diff fails if actually used. Solution: Invoke :diffupdate in the test. Fix the check for working external diff. (Ghjuvan Lacambre, Christian Brabandt, closes #8197)

TYPEMAP
VIWIN	T_VIOBJNOMUNGE
VIBUF	T_VIOBJNOMUNGE

INPUT
T_VIOBJNOMUNGE
	if (sv_isa($arg, \"${ntype}\")) {
	    IV tmp = SvIV((SV*)SvRV($arg));
	    $var = INT2PTR($type, tmp);
	    if (!tmp)
		croak(\"$ntype no longer exists\");
	}
	else
	    croak(\"$var is not of type ${ntype}\")