Fix new recovery test for use under msys

Commit caba8f0d wasn't quite right for msys, as demonstrated by
several buildfarm animals, including jacana and fairywren. We need to
use the msys perl in the archive command, but call it in such a way that
Windows will understand the path. Furthermore, inside the copy script we
need to convert a Windows path to an msys path.

src/test/recovery/t/025_stuck_on_old_timeline.pl

@@ -10,6 +10,8 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
+
+use File::Basename;
 use FindBin;
 use Test::More tests => 1;
 
@@ -23,12 +25,17 @@ my $node_primary = get_new_node('primary');
 # get there.
 $node_primary->init(allows_streaming => 1, has_archiving => 1);
 my $perlbin = $^X;
-$perlbin =~ s{\\}{\\\\}g if ($TestLib::windows_os);
+if ($^O eq 'msys')
+{
+	$perlbin = TestLib::perl2host(dirname($^X)) . '\\' . basename($^X);
+}
+$perlbin =~ s!\\!/!g if $TestLib::windows_os;
 my $archivedir_primary = $node_primary->archive_dir;
 $node_primary->append_conf('postgresql.conf', qq(
-archive_command = '$perlbin "$FindBin::RealBin/cp_history_files" "%p" "$archivedir_primary/%f"'
+archive_command = '"$perlbin" "$FindBin::RealBin/cp_history_files" "%p" "$archivedir_primary/%f"'
 wal_keep_size=128MB
 ));
+local $ENV{PERL_BADLANG}=0;
 $node_primary->start;
 
 # Take backup from primary
@@ -74,7 +81,8 @@ $node_standby->safe_psql('postgres', 'SELECT pg_switch_wal()');
 # WAL segment, this is enough to guarantee that the history file was
 # archived.
 my $archive_wait_query =
-  "SELECT '$walfile_to_be_archived' <= last_archived_wal FROM pg_stat_archiver;";
+  "SELECT coalesce('$walfile_to_be_archived' <= last_archived_wal, false) " .
+  "FROM pg_stat_archiver";
 $node_standby->poll_query_until('postgres', $archive_wait_query)
   or die "Timed out while waiting for WAL segment to be archived";
 my $last_archived_wal_file = $walfile_to_be_archived;

src/test/recovery/t/cp_history_files

@@ -7,4 +7,11 @@ use warnings;
 die "wrong number of arguments" if @ARGV != 2;
 my ($source, $target) = @ARGV;
 exit if $source !~ /history/;
+if ($^O eq 'msys')
+{
+    # make a windows path look like an msys path if necessary
+    $source =~ s!^([A-Za-z]):!'/' . lc($1)!e;
+    $source =~ s!\\!/!g;
+}
+
 copy($source, $target) or die "couldn't copy $source to $target: $!";