X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/363ae066badd453c806244ee48a0f18da4643261..2a283885f92b85ae047ff92372b5fb1df1f9ef9c:/buildtools/Cmake/tesh.pl

diff --git a/buildtools/Cmake/tesh.pl b/buildtools/Cmake/tesh.pl
index 87e6adc2e0..28296d6a32 100755
--- a/buildtools/Cmake/tesh.pl
+++ b/buildtools/Cmake/tesh.pl
@@ -1,296 +1,436 @@
-#! /usr/bin/perl -w
+#! /usr/bin/perl
+eval 'exec perl -S $0 ${1+"$@"}'
+    if $running_under_some_shell;
 
+=encoding UTF-8
+
+=head1 NAME
+
+tesh -- testing shell
+
+=head1 SYNOPSIS
+
+B<tesh> [I<options>] I<tesh_file>
+
+=cut
+my($bindir);
+my($srcdir);
+my $path = $0;
+$path =~ s|[^/]*$||;
+push @INC,$path;
+
+use Getopt::Long qw(GetOptions);
 use strict;
+use Term::ANSIColor;
+use IPC::Open3;
 
-if($#ARGV<0){die "Usage: tesh.pl <options> <teshfile.tesh>\n";}
-my($line1);
-my($line2);
-my($execline);
-my($ok)=0;
-my($ok1)=0;
-my($sort)=0;
-my($nb_arg)=0;
-my($result);
-my(@list1)=();
-my(@list2)=();
-my(@list3)=();
-my(@buffer)=();
-my($timeout)=-1;
-my($parallel)=0;
-my($verbose)=0;
-my($encore)=0;
-my($old_buffer);
+my($OS)=`echo %OS%`;
+if($OS eq "%OS%"){
+	$OS = "UNIX";
+}
+else{
+	$OS = "WIN";
+}
 
-#options
-do{
-	if($ARGV[$nb_arg] =~ /^--cd$/)
-	{
-		$nb_arg++;
-		if(!$ARGV[$nb_arg] or $ARGV[$nb_arg] =~ /^--/){die "Usage: tesh.pl --cd <directory>\n";}
-		my($directory)=$ARGV[$nb_arg];
-		if( -e $directory) 
-		{
-			chdir("$directory");
-			print "[Tesh/INFO] Change directory to \"$directory\"\n";
-		}
-		else
-		{
-			die "[Tesh/CRITICAL] Directory not found : \"$directory\"\n";
-		}
-		$nb_arg++;	
-	}
-	elsif($ARGV[$nb_arg] =~ /^--setenv$/)
-	{
-		$nb_arg++;
-		if(!$ARGV[$nb_arg] or $ARGV[$nb_arg] =~ /^--/){die "Usage: tesh.pl --setenv environment_variable\n";}
-		if(!$ARGV[$nb_arg+1] or $ARGV[$nb_arg+1] =~ /^--/){die "Usage: tesh.pl --setenv environment_variable\n";}
-		$ENV{$ARGV[$nb_arg]} = "$ENV{$ARGV[$nb_arg]}:$ARGV[$nb_arg+1]";
-		print "[Tesh/INFO] export $ARGV[$nb_arg]=\"$ENV{$ARGV[$nb_arg]}\"\n";
-		$nb_arg++;
-		$nb_arg++;
-	}
-	elsif($ARGV[$nb_arg] =~ /^--verbose$/)
-	{
-		$verbose=1;
-	}
-	else
-	{
-		print "[Tesh/CRITICAL] Unrecognized option : $ARGV[$nb_arg]\n";
-		$nb_arg++;
-	}
-}while(($nb_arg) < $#ARGV);
+# make sure we received a tesh file
+scalar @ARGV > 0 || die "Usage:\n    tesh [*options*] *tesh_file*\n";
 
 #Add current directory to path
 $ENV{PATH} = "$ENV{PATH}:.";
 
-#tesh file
-if(!$ARGV[$nb_arg]){die "tesh.pl <options> <teshfile.tesh>\n";}
-print "[Tesh/INFO] load file : $ARGV[$nb_arg]\n";
-my($file)=$ARGV[$nb_arg];
-open SH_LIGNE, $file or die "[Tesh/CRITICAL] Unable to open $file. $!\n";
-
-while(defined($line1=<SH_LIGNE>))
-{
-	if($line1 =~ /^\$ /){  	#command line
-		$line1 =~ s/\$\{srcdir\:\=\.\}/./g;
-		$line1 =~ s/\${EXEEXT:=}//g;
-		$line1 =~ s/^\$\ *//g;
-		$line1 =~ s/^.\/lua/lua/g;
-		$line1 =~ s/^.\/ruby/ruby/g;
-		$line1 =~ s/^.\///g;
-		$line1 =~ s/\(%i:%P@%h\)/\\\(%i:%P@%h\\\)/g;
-		chomp $line1;
-		if(@list1){
-			print "[Tesh/CRITICAL] Old result : @list1";
-			print "[Tesh/CRITICAL] Previous result not check!";
-			die;}
-		if($parallel == 1)
-		{
-			$execline = "$execline \& $line1 2>&1";
-			print "[Tesh/INFO] exec_line // : $execline\n";
-		}
-		else
-		{
-			$ok = 1;
-			$execline = "$line1  2>&1";
-			print "[Tesh/INFO] exec_line : $execline\n";
-			$result=`$execline`;
-			@list1 = split(/\n/,$result);
-		}
+
+##
+## Command line option handling
+##
+
+# option handling helper subs
+sub cd_cmd {
+    my $directory=$_[1];
+    if (-e $directory && -d $directory) {
+	chdir("$directory");
+	print "[Tesh/INFO] change directory to $directory\n";
+    } elsif (-e $directory) {
+	die "[Tesh/CRITICAL] Cannot change directory to '$directory': it is not a directory\n";
+    } else {
+	die "[Tesh/CRITICAL] Cannot change directory to '$directory': no such directory\n";
+    }
+}
+
+sub setenv_cmd {
+    if ($_[1] =~ /^(.*)=(.*)$/) {
+	my($var,$ctn)=($1,$2);
+	
+	if($var =~ /bindir/){
+		print "[Tesh/INFO] setenv $var=$ctn\n";
+		$bindir = $ctn;
 	}
-	elsif($line1 =~ /^\& /){  	# parallel command line
-		$line1 =~ s/\$\{srcdir\:\=\.\}/./g;
-		$line1 =~ s/\${EXEEXT:=}//g;
-		$line1 =~ s/^\& //g;
-		$line1 =~ s/^.\/lua/lua/g;
-		$line1 =~ s/^.\/ruby/ruby/g;
-		$line1 =~ s/^.\///g;
-		$line1 =~ s/\(%i:%P@%h\)/\\\(%i:%P@%h\\\)/g;
-		chomp $line1;
-		if(@list1){
-			print "Old result : @list1";
-			die "Previous result not check!";}
-		if($parallel == 1)
-		{
-			$execline = "$execline \& $line1  2>&1";
-			print "[Tesh/INFO] exec_line // : $execline\n";
+	else
+	{
+		if($var =~ /srcdir/){
+			$srcdir = $ctn;
 		}
-		else
-		{
-			$parallel = 1;
-			$execline = "$line1 2>&1";
-			print "[Tesh/INFO] exec_line // : $execline\n";
+		else{
+			$ENV{$var} = $ctn;
+			print "[Tesh/INFO] setenv $var=$ctn\n";
 		}
-		
 	}	
-	elsif($line1 =~ /^\>/){	#expected result line
-		if($ok == 0 and $parallel== 0){die "No command line\n";}
-		$ok1 = 1;
-		$line1 =~ s/^\> //g;
-		$line1 =~ s/\r//g;
-		chomp $line1;
-		push @list2, $line1;
-	}
-	elsif($line1 =~ /^\</ or $encore==1){	#need to buffer
-		$line1 =~ s/^\< //g;
-		$line1 =~ s/\r//g;
-		chomp $line1;
-		if($line1 =~ /\\$/) # need to store this line into old_buff
-		{
-			$encore=1;
-			$line1 =~ s/\\$//g;
-			$old_buffer = "$old_buffer$line1";
-		}
-		else
-		{
-			if($encore == 1)
-			{	
-				push @buffer, "$old_buffer$line1";
-				$old_buffer = ();
-				$encore = 0;				
-			}
-			else
-			{
-				push @buffer, "$line1\n";
-				$old_buffer = ();
-				$encore = 0;					
-			}
-		}
-	}
-	elsif($line1 =~ /^p/){	#comment
-		$line1 =~ s/^p //g;
-		$line1 =~ s/\r//g;
-		chomp $line1;
-		print "[Tesh/INFO] comment_line :$line1\n";
+	} else { 
+	die "[Tesh/CRITICAL] Malformed argument to setenv: expected 'name=value' but got '$_[1]'\n";
+    }
+}
+
+# Main option parsing sub
+my $tesh_file;
+sub get_options {
+    # remove the tesh file from the ARGV used
+    my @ARGV = @_;
+    $tesh_file = pop @ARGV;
+
+    # temporary arrays for GetOption
+    my @verbose = ();
+    my @cfg;
+    my $log; # ignored
+
+    my %opt = (
+	"help"    => 0,
+	"debug"   => 0,
+	"verbose" => 0
+	);
+
+    Getopt::Long::config('bundling', 'no_getopt_compat', 'no_auto_abbrev');
+    
+    GetOptions(
+	'help|h'     => \$opt{'help'},
+
+        'verbose|v'  => \@verbose,
+        'debug|d'    => \$opt{"debug"},
+
+	'cd=s'       => \&cd_cmd,
+	'setenv=s'   => \&setenv_cmd,
+	'cfg=s'      => \@cfg,
+	'log=s'      => \$log,
+	);
+
+    $opt{'verbose'} = scalar @verbose;
+    foreach (@cfg) {
+	$opt{'cfg'} .= " --cfg=$_";
+    }
+    return %opt;
+}
+
+my %opts = get_options(@ARGV);
+
+##
+## File parsing
+##
+my($sort)=0;
+my($nb_arg)=0;
+my($timeout)=0;
+my($old_buffer);
+my($linebis);
+my($SIGABRT)=0;
+my($no_output_ignore)=1;
+my($verbose)=0;
+my($return)=-1;
+my($pid);
+my($result);
+my($result_err);
+my($forked);
+my($config)="";
+
+my($tesh_command)=0;
+my(@buffer_tesh)=();
+
+eval {
+    use POSIX;
+    sub exit_status {
+	my $status = shift;
+	if (POSIX::WIFEXITED($status)) {
+	    return "returned code ".POSIX::WEXITSTATUS($status);
+	} elsif (POSIX::WIFSIGNALED($status)) {
+	    return "got signal ".$SIG{POSIX::WTERMSIG($status)};
 	}
-	elsif($line1 =~ /^! output sort/){	#output sort
-		print "[Tesh/INFO] output sort\n";
-		$sort=1;
+	return "Unparsable status. Is the process stopped?";
+    }
+};
+if ($@) { # no POSIX available?
+    warn "POSIX not usable to parse the return value of forked child: $@\n";
+    sub exit_status {
+	return "returned code 0";
+    }
+}
+
+sub exec_cmd { 
+    my %cmd = %{$_[0]};
+    if ($opts{'debug'}) {
+	print "IN BEGIN\n";
+	map {print "  $_"} @{$cmd{'in'}};
+	print "IN END\n";
+	print "OUT BEGIN\n";
+	map {print "  $_"} @{$cmd{'out'}};
+	print "OUT END\n";
+	print "CMD: $cmd{'cmd'}\n";
+    }
+
+    # cleanup the command line
+    if($OS eq "WIN"){
+		$cmd{'cmd'} =~ s/\${EXEEXT:=}/.exe/g;
 	}
-	elsif($line1 =~ /^! expect return/){	#expect sort
-		print "[Tesh/CRITICAL] expect return\n";
-		die;
+	else{
+		$cmd{'cmd'} =~ s/\${EXEEXT:=}//g;
 	}
-	elsif($line1 =~ /^! setenv/){	#setenv
-		$line1 =~ s/^! setenv //g;
-		$line1 =~ s/\r//g;
-		chomp $line1;
-		$line1 =~ /^(.*)=(.*)$/;
-		$ENV{$1} = $2;
-		print "[Tesh/INFO] setenv: $1=$2\n";
+    $cmd{'cmd'} =~ s/\${bindir:=}/$bindir/g;
+    $cmd{'cmd'} =~ s/\${srcdir:=}/$srcdir/g;
+    $cmd{'cmd'} =~ s/\${bindir:=.}/$bindir/g;
+    $cmd{'cmd'} =~ s/\${srcdir:=.}/$srcdir/g;
+    $cmd{'cmd'} =~ s/\${bindir}/$bindir/g;
+    $cmd{'cmd'} =~ s/\${srcdir}/$srcdir/g;
+    $cmd{'cmd'} =~ s|^\./||g;
+#    $cmd{'cmd'} =~ s|tesh|tesh.pl|g;
+    $cmd{'cmd'} =~ s/\(%i:%P@%h\)/\\\(%i:%P@%h\\\)/g;
+    $cmd{'cmd'} .= " $opts{'cfg'}" if (defined($opts{'cfg'}) && length($opts{'cfg'}));
+
+    print "[$cmd{'file'}:$cmd{'line'}] $cmd{'cmd'}\n";
+
+    ###
+    # exec the command line
+    ###
+    $pid = open3(\*IN, \*OUT, \*OUT, $cmd{'cmd'} );
+
+    # if timeout specified, fork and kill executing child at the end of timeout
+    if ($timeout){
+	$forked = fork();
+	die "fork() failed: $!" unless defined $forked;
+	if ( $forked == 0 ) { # child
+	    sleep $timeout;
+	    kill(9, $pid);
+	    exit;
 	}
-	elsif($line1 =~ /^! include/){	#output sort
-		die "[Tesh/CRITICAL] need include\n";
+    }
+
+    # push all provided input to executing child
+    map { print IN "$_\n" } $cmd{'in'};
+    close IN;
+
+    # pop all output from executing child
+    my @got;
+    while(defined(my $got=<OUT>)) {
+	$got =~ s/\r//g;
+	#$got =~ s/^( )*//g;
+	chomp $got;
+	push @got, "$got";
+    }	
+    close OUT;
+    
+    # Cleanup the executing child, and kill the timeouter brother on need
+    $cmd{'return'} = 0 unless defined($cmd{'return'});
+    my $wantret = "returned code ".(defined($cmd{'return'})? $cmd{'return'} : 0);
+    waitpid ($pid, 0);
+    my $gotret = exit_status($?);
+    if($gotret ne $wantret) {
+	my $msg = "Test suite `$cmd{'file'}': NOK (<$cmd{'file'}:$cmd{'line'}> $gotret)\n".
+	    "Output of <$cmd{'file'}:$cmd{'line'}> so far:\n";      
+	map {$msg .=  "|| $_\n"} @got;
+	print STDERR "$msg";
+	exit(1);
+    }
+    if($timeout){kill(9, $forked);$timeout=0;}
+    $timeout = 0;
+	    
+    ###
+    # Check the result of execution 
+    ###
+    my $diff = build_diff(\@{$cmd{'out'}}, \@got);
+    if (length $diff) {
+	print color("red")."[TESH/CRITICAL$$] Output mismatch\n";
+	map { print "[TESH/CRITICAL] $_\n" } split(/\n/,$diff);
+	print color("reset");
+	die "Tesh failed\n";
+    }
+}
+
+sub mkfile_cmd {
+    my %cmd = %{$_[0]};
+    my $file = $cmd{'arg'};
+    print "[Tesh/INFO] mkfile $file\n";
+
+    die "[TESH/CRITICAL] no input provided to mkfile\n" unless defined($cmd{'in'}) && scalar @{$cmd{'in'}};
+    unlink($file);
+    open(FILE,">$file") or die "[Tesh/CRITICAL] Unable to create file $file: $!\n";
+    print FILE join("\n", @{$cmd{'in'}});
+    print FILE "\n" if (scalar @{$cmd{'in'}} > 0);
+    close(FILE);
+}
+
+# parse tesh file
+print "Test suite $tesh_file\n";
+open TESH_FILE, $tesh_file or die "[Tesh/CRITICAL] Unable to open $tesh_file $!\n";
+
+
+my %cmd; # everything about the next command to run
+my $line_num=0;
+LINE: while (defined(my $line=<TESH_FILE>)) {
+    $line_num++;
+    chomp $line;
+    print "[TESH/debug] $line_num: $line\n" if $opts{'debug'};
+
+    # deal with line continuations
+    while ($line =~ /^(.*?)\\$/) {
+	my $next=<TESH_FILE>;
+	die "[TESH/CRITICAL] Continued line at end of file\n"
+	    unless defined($next);
+	chomp $next;
+	print "[TESH/debug] $line_num: $next\n" if $opts{'debug'};
+	$line = $1.$next;
+    }
+
+    # Push delayed commands on empty lines
+    unless ($line =~ m/^(..)(.*)$/) {
+	if (defined($cmd{'cmd'})) {
+	    exec_cmd(\%cmd);
+	    %cmd = ();
 	}
-	elsif($line1 =~ /^! timeout/){	#timeout
-		$line1 =~ s/^! timeout //g;
-		$line1 =~ s/\r//g;
-		chomp $line1;
-		$timeout = $line1;
-		print "[Tesh/INFO] timeout   : $timeout\n";
+	next LINE;
+    } 	
+ 
+    my ($cmd,$arg) = ($1,$2);
+    $arg =~ s/\r//g;
+
+    # handle the commands
+    if ($cmd =~ /^#/) {	#comment
+    } elsif ($cmd eq '> '){	#expected result line
+	print "[TESH/debug] push expected result\n" if $opts{'debug'};
+	push @{$cmd{'out'}}, $arg;
+
+    } elsif ($cmd eq '< ') {	# provided input
+	print "[TESH/debug] push provided input\n" if $opts{'debug'};
+	push @{$cmd{'in'}}, $arg;
+
+    } elsif ($cmd eq 'p ') {	# comment
+	print "[Tesh/INFO] $arg\n";
+
+    } elsif ($cmd eq '$ ') {  # Command
+	# if we have something buffered, run it now
+	if (defined($cmd{'cmd'})) {
+	    exec_cmd(\%cmd);
+	    %cmd = ();
 	}
-	elsif($ok == 1 and $ok1 == 1)
-	{
-		@buffer = ();
-		if($sort == 1)
-		{
-			@list3 = sort @list1;
-			@list1=();
-			@list1=@list3;
-			@list3=();
-			
-			@list3 = sort @list2;
-			@list2=();
-			@list2=@list3;
-			@list3=();
-			
-			$sort=0;
-		}
-		while(@list1 or @list2)
-		{
-			$line1 = shift (@list1);
-			$line2 = shift (@list2);
-			if($line2 and $line1)
-			{
-				if($line1 eq $line2){
-					if($verbose == 1){print "$line1\n";}
-					else{push @buffer, "$line1\n";}
-					
-				}
-				else
-				{	if($verbose == 0){print @buffer};
-					if($line2) {print "- $line2\n"};
-					if($line1) {print "+ $line1\n"};
-					die;
-				}
-			}
-			else
-			{	if($verbose == 0){print @buffer};
-				if($line2) {print "- $line2\n"};
-				if($line1) {print "+ $line1\n"};
-				die;
-			}
-		}
-		$ok = 0;
-		$ok1= 0;
-		@list1=();
-		@list2=();
-		@buffer = ();
-		$result = ();
+	if ($arg =~ /^ *mkfile /){  	# "mkfile" command line
+	    die "[TESH/CRITICAL] Output expected from mkfile command!\n" if scalar @{cmd{'out'}};
+
+	    $cmd{'arg'} = $arg;
+	    $cmd{'arg'} =~ s/ *mkfile //;
+	    mkfile_cmd(\%cmd);
+	    %cmd = ();
+
+	} elsif ($arg =~ /^ *cd /) {
+	    die "[TESH/CRITICAL] Input provided to cd command!\n" if scalar @{cmd{'in'}};
+	    die "[TESH/CRITICAL] Output expected from cd command!\n" if scalar @{cmd{'out'}};
+
+	    $arg =~ s/^ *cd //;
+	    cd_cmd("",$arg);
+	    %cmd = ();
+
+	} else { # regular command
+	    $cmd{'cmd'} = $arg;
+	    $cmd{'file'} = $tesh_file;
+	    $cmd{'line'} = $line_num;
 	}
+    }
+    elsif($cmd eq '& '){  	# parallel command line
+	$cmd{'background'} = 1;
+	$cmd{'cmd'} = $arg;
+    }	
+    elsif($line =~ /^! output sort/){	#output sort
+	$cmd{'sort'} = 1;
+    }
+    elsif($line =~ /^! output ignore/){	#output ignore
+	$cmd{'output ignore'} = 1;
+    }
+    elsif($line =~ /^! expect signal SIGABRT$/) {#expect signal SIGABRT
+	$cmd{'expect'} = "SIGABRT";
+    }
+    elsif($line =~ /^! expect return/){	#expect return
+	$line =~ s/^! expect return //g;
+	$line =~ s/\r//g;
+	$cmd{'return'} = $line;
+    }
+    elsif($line =~ /^! setenv/){	#setenv
+	$line =~ s/^! setenv //g;
+	$line =~ s/\r//g;
+	setenv_cmd($line);
+    }
+    elsif($line =~ /^! include/){	#output sort
+	print color("red"), "[Tesh/CRITICAL] need include";
+	print color("reset"), "\n";
+	die;
+    }
+    elsif($line =~ /^! timeout/){	#timeout
+	$line =~ s/^! timeout //;
+	$line =~ s/\r//g;
+	$cmd{'timeout'} = $line;
+    } else {
+	die "[TESH/CRITICAL] parse error: $line\n";
+    }
 }
 
-if($parallel == 1)
-{
-	$ok = 1;
-	$result=`$execline`;
-	@list1 = split(/\n/,$result);
+# Deal with last command
+if (defined($cmd{'cmd'})) {
+    exec_cmd(\%cmd);
+    %cmd = ();
 }
-elsif($ok == 1 and $ok1 == 1)
-		{
-			@buffer = ();
-			if($sort == 1)
-			{
-				@list3 = sort @list1;
-				@list1=();
-				@list1=@list3;
-				@list3=();
-				
-				@list3 = sort @list2;
-				@list2=();
-				@list2=@list3;
-				@list3=();
-				
-				$sort=0;
-			}
-			while(@list1 or @list2)
-			{
-				$line1 = shift (@list1);
-				$line2 = shift (@list2);
-				if($line2 and $line1)
-				{
-					if($line1 eq $line2){
-						if($verbose == 1){print "$line1\n";}
-						else{push @buffer, "$line1\n";}
-						
-					}
-					else
-					{	if($verbose == 0){print @buffer};
-						if($line2) {print "- $line2\n"};
-						if($line1) {print "+ $line1\n"};
-						die;
-					}
-				}
-				else
-				{	if($verbose == 0){print @buffer};
-					if($line2) {print "- $line2\n"};
-					if($line1) {print "+ $line1\n"};
-					die;
-				}
-			}
-			$ok = 0;
-			$ok1= 0;
-			@list1=();
-			@list2=();
-			@buffer = ();
-}
\ No newline at end of file
+
+#my (@a,@b);
+#push @a,"bl1";   push @b,"bl1";
+#push @a,"bl2";   push @b,"bl2";
+#push @a,"bl3";   push @b,"bl3";
+#push @a,"bl4";   push @b,"bl4";
+#push @a,"bl5";   push @b,"bl5";
+#push @a,"bl6";   push @b,"bl6";
+#push @a,"bl7";   push @b,"bl7";
+##push @a,"Perl";  push @b,"ruby";
+#push @a,"END1";   push @b,"END1";
+#push @a,"END2";   push @b,"END2";
+#push @a,"END3";   push @b,"END3";
+#push @a,"END4";   push @b,"END4";
+#push @a,"END5";   push @b,"END5";
+#push @a,"END6";   push @b,"END6";
+#push @a,"END7";   push @b,"END7";
+#print "Identical:\n". build_diff(\@a,\@b);
+
+#@a = (); @b =();
+#push @a,"AZE"; push @b,"EZA";
+#print "Different:\n".build_diff(\@a,\@b);
+
+use Diff qw(diff); # postpone a bit to have time to change INC
+
+sub build_diff {
+    my $res;
+    my $diff = Diff->new(@_);
+    
+    $diff->Base( 1 );   # Return line numbers, not indices
+    my $chunk_count = $diff->Next(-1); # Compute the amount of chuncks
+    return ""     if ($chunk_count == 1 && $diff->Same());
+    $diff->Reset();
+    while(  $diff->Next()  ) {
+	my @same = $diff->Same();
+	if ($diff->Same() ) {
+	    if ($diff->Next(0) > 1) { # not first chunk: print 2 first lines
+		$res .= '  '.$same[0]."\n" ;
+		$res .= '  '.$same[1]."\n" if (scalar @same>1);
+	    } 	
+	    $res .= "...\n"  if (scalar @same>2);
+#	$res .= $diff->Next(0)."/$chunk_count\n";
+	    if ($diff->Next(0) < $chunk_count) { # not last chunk: print 2 last lines
+		$res .= '  '.$same[scalar @same -2]."\n" if (scalar @same>1);
+		$res .= '  '.$same[scalar @same -1]."\n";
+	    } 
+	} 
+	next if  $diff->Same();
+	map { $res .= "- $_\n" } $diff->Items(1);
+	map { $res .= "+ $_\n" } $diff->Items(2);
+    }
+    return $res;
+}
+
+