patch 8.2.2847: Perl not tested sufficiently

Problem:    Perl not tested sufficiently.
Solution:   Add test.  Also test W17. (Dominique Pellé, closes #8193)
diff --git a/src/testdir/test_arabic.vim b/src/testdir/test_arabic.vim
index 2729373..73b85c4 100644
--- a/src/testdir/test_arabic.vim
+++ b/src/testdir/test_arabic.vim
@@ -584,4 +584,12 @@
   bwipe!
 endfunc
 
+func Test_W17_arabic_requires_utf8()
+  let save_enc = &encoding
+  set encoding=latin1 arabic
+  call assert_match('^W17:', GetMessages()[-1])
+  set arabic&
+  let &encoding = save_enc
+endfunc
+
 " vim: shiftwidth=2 sts=2 expandtab
diff --git a/src/testdir/test_perl.vim b/src/testdir/test_perl.vim
index c6427a7..c35f49c 100644
--- a/src/testdir/test_perl.vim
+++ b/src/testdir/test_perl.vim
@@ -1,6 +1,7 @@
 " Tests for Perl interface
 
 source check.vim
+source shared.vim
 CheckFeature perl
 
 " FIXME: RunTest don't see any error when Perl abort...
@@ -52,6 +53,11 @@
   perl @l = ('5' ..'7')
   perl $curbuf->Append(0, @l)
   call assert_equal(['5', '6', '7', '', '1', '2', '3', '4'], getline(1, '$'))
+
+  perl $curbuf->Append(0)
+  call assert_match('^Usage: VIBUF::Append(vimbuf, lnum, @lines) at .* line 1\.$',
+        \           GetMessages()[-1])
+
   bwipe!
 endfunc
 
@@ -61,6 +67,11 @@
   perl $curbuf->Set(2, 'a', 'b', 'c')
   perl $curbuf->Set(4, 'A', 'B', 'C')
   call assert_equal(['1', 'a', 'b', 'A', 'B'], getline(1, '$'))
+
+  perl $curbuf->Set(0)
+  call assert_match('^Usage: VIBUF::Set(vimbuf, lnum, @lines) at .* line 1\.$',
+        \           GetMessages()[-1])
+
   bwipe!
 endfunc
 
@@ -210,6 +221,13 @@
   perldo VIM::DoCommand("%d_")
   bwipe!
 
+  " Check a Perl expression which gives an error.
+  new
+  call setline(1, 'one')
+  perldo 1/0
+  call assert_match('^Illegal division by zero at .* line 1\.$', GetMessages()[-1])
+  bwipe!
+
   " Check switching to another buffer does not trigger ml_get error.
   new
   let wincount = winnr('$')
@@ -231,12 +249,13 @@
 func Test_stdio()
   redir =>l:out
   perl << trim EOF
-    VIM::Msg("&VIM::Msg");
+    VIM::Msg("VIM::Msg");
+    VIM::Msg("VIM::Msg Error", "Error");
     print "STDOUT";
     print STDERR "STDERR";
   EOF
   redir END
-  call assert_equal(['&VIM::Msg', 'STDOUT', 'STDERR'], split(l:out, "\n"))
+  call assert_equal(['VIM::Msg', 'VIM::Msg Error', 'STDOUT', 'STDERR'], split(l:out, "\n"))
 endfunc
 
 " Run first to get a clean namespace