PT-2503 - pt-eustack-resolver does not have --version option

- Cleaned warnings seen before
- Added test case

bin/pt-eustack-resolver

@@ -5,7 +5,7 @@
 # notices and disclaimers.
 
 use strict;
-#use warnings FATAL => 'all';
+use warnings FATAL => 'all';
 
 # This tool is "fat-packed": most of its dependent modules are embedded
 # in this file.  Setting %INC to this file for each module makes Perl aware
@@ -1247,7 +1247,6 @@ if ( PTDEBUG ) {
 # End OptionParser package
 # ###########################################################################
 
-
 # ###########################################################################
 # This is a combination of modules and programs in one -- a runnable module.
 # http://www.perl.com/pub/a/2006/07/13/lightning-articles.html?page=last
@@ -1259,7 +1258,10 @@ if ( PTDEBUG ) {
 package pt_eu_stack_resolver;
 
 use strict;
-#use warnings FATAL => 'all';
+use warnings FATAL => 'all';
+# We have to disable warnings here because Perl prints
+# warnings for numbers greater than 2^32.
+no warnings 'portable';
 
 use Percona::Toolkit;
 use constant PTDEBUG => $ENV{PTDEBUG} || 0;
@@ -1370,7 +1372,7 @@ sub load_mapping {
       push @$arr, { S => hex($1), E => hex($2), B => hex($3), F => $4 };
    }
    close $FH;
-   sort { $a->{S} <=> $b->{S} } @$arr;
+   @$arr = sort { $a->{S} <=> $b->{S} } @$arr;
    return $arr;
 }
 
@@ -1414,7 +1416,7 @@ and resolve symbols.
 
 Usage: pt-eustack-resolver PID
 
-pt-eustack-resolver collects stack traces for the process with specified C<pid>.
+pt-eustack-resolver collects stack traces for the process with specified C<PID>.
 
 =head1 RISKS
 
@@ -1463,7 +1465,6 @@ Show help and exit.
 
 Show version and exit.
 
-
 =head1 ATTENTION
 
 Using <PTDEBUG> might expose passwords. When debug is enabled, all command line

t/pt-eustack-resolver/option_sanity.t

@@ -0,0 +1,70 @@
+#!/usr/bin/env perl
+
+BEGIN {
+   die "The PERCONA_TOOLKIT_BRANCH environment variable is not set.\n"
+      unless $ENV{PERCONA_TOOLKIT_BRANCH} && -d $ENV{PERCONA_TOOLKIT_BRANCH};
+   unshift @INC, "$ENV{PERCONA_TOOLKIT_BRANCH}/lib";
+};
+
+use strict;
+use warnings FATAL => 'all';
+use English qw(-no_match_vars);
+use Test::More;
+
+use PerconaTest;
+
+# ############################################################################
+# We only check basic option sanity here. It is hard to create tests for the
+# eu-stack output that work in all environments. So we will simply check that
+# the help and version options work as expected.
+# ############################################################################
+
+my $output = `$trunk/bin/pt-eustack-resolver --help`;
+
+like(
+   $output,
+   qr/^\s+--help\s+Show help and exit/m,
+   "--help option is documented"
+);
+
+like(
+   $output,
+   qr/^\s+--version\s+Show version and exit/m,
+   "--version option is documented"
+);
+
+like(
+   $output,
+   qr/Options and values after processing arguments:/m,
+   "Help output contains expected section"
+);
+
+# ############################################################################
+# Check error when no arguments are provided
+# ############################################################################
+my $error_output = `$trunk/bin/pt-eustack-resolver 2>&1`;
+
+like(
+   $error_output,
+   qr/A PID must be specified/m,
+   "Error message shown when no PID is provided"
+);
+
+like(
+   $error_output,
+   qr/Usage: pt-eustack-resolver PID/m,
+   "Usage line shown in error"
+);
+
+# ############################################################################
+# Check --version option
+# ############################################################################
+my $version_output = `$trunk/bin/pt-eustack-resolver --version`;
+
+like(
+   $version_output,
+   qr/pt-eustack-resolver \d+\.\d+\.\d+(?:-\d+)?/m,
+   "--version shows tool name and version"
+);
+
+done_testing;