Convenience function to check for 1/0/true/false/on/off/yes/no

C4/Boolean.pm

@@ -0,0 +1,124 @@
+package C4::Boolean;
+
+# $Id$
+
+#package to handle Boolean values in the parameters table
+# Note: This is just a utility module; it should not be instantiated.
+
+
+# Copyright 2003 Katipo Communications
+#
+# This file is part of Koha.
+#
+# Koha is free software; you can redistribute it and/or modify it under the
+# terms of the GNU General Public License as published by the Free Software
+# Foundation; either version 2 of the License, or (at your option) any later
+# version.
+#
+# Koha is distributed in the hope that it will be useful, but WITHOUT ANY
+# WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
+# A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License along with
+# Koha; if not, write to the Free Software Foundation, Inc., 59 Temple Place,
+# Suite 330, Boston, MA  02111-1307 USA
+
+use strict;
+use POSIX;
+require Exporter;
+
+use vars qw($VERSION @ISA @EXPORT @EXPORT_OK);
+
+# set the version for version checking
+$VERSION = 0.01;
+
+=head1 NAME
+
+C4::Boolean - Convenience functions to handle boolean values
+in the parameter table
+
+=head1 SYNOPSIS
+
+  use C4::Boolean;
+
+=head1 DESCRIPTION
+
+In the parameter table, there are various Boolean values that
+variously require a 0/1, no/yes, false/true, or off/on values.
+This module aims to provide scripts a means to interpret these
+Boolean values in a consistent way which makes common sense.
+
+=head1 FUNCTIONS
+
+=over 2
+
+=cut
+
+@ISA = qw(Exporter);
+@EXPORT = (
+	&INVALID_BOOLEAN_STRING_EXCEPTION
+    );
+
+@EXPORT_OK = qw(
+	true_p
+    );
+
+sub INVALID_BOOLEAN_STRING_EXCEPTION ()
+    { 'The given value does not seem to be interpretable as a Boolean value' }
+
+use vars qw( %strings );
+
+%strings = (
+   '0'     => 0,	'1'     => 1,	# C
+   			'-1'    => 1,	# BASIC
+   'nil'   => 0,	't'     => 1,	# LISP
+   'false' => 0,	'true'  => 1,	# Pascal
+   'off'   => 0,	'on'    => 1,
+   'no'    => 0,	'yes'   => 1,
+   'n'     => 0,	'y'     => 1,
+);
+
+=item true_p
+
+    if ( C4::Boolean::true_p(C4::Context->preference("insecure")) ) {
+	...
+    }
+
+Tries to interpret the passed string as a Boolean value. Returns
+the value if the string can be interpreted as such; otherwise an
+exception is thrown.
+
+=cut
+
+require '/u/acli/lib/cvs.pl';
+sub true_p ($) {
+    my($x) = @_;
+    my $it;
+    if (!defined $x || ref($x) ne '') {
+	die INVALID_BOOLEAN_STRING_EXCEPTION;
+    }
+    $x = lc($x);
+    $x =~ s/\s//g;
+    if (defined $strings{$x}) {
+	$it = $strings{$x};
+    } else {
+	die INVALID_BOOLEAN_STRING_EXCEPTION;
+    }
+    return $it;
+}
+
+
+#---------------------------------
+
+END { }       # module clean-up code here (global destructor)
+
+1;
+__END__
+
+=back
+
+=head1 AUTHOR
+
+Koha Developement team <info@koha.org>
+
+=cut

t/Boolean.t

@@ -0,0 +1,92 @@
+use strict;
+use C4::Boolean;
+
+use vars qw( @tests );
+use vars qw( $loaded );
+
+sub f ($) {
+   my($x) = @_;
+   my $it;
+   # Returns either the value returned prefixed with 'OK:',
+   # or the caught exception (string expected)
+   local($@);
+   eval {
+      $it = 'OK:' . C4::Boolean::true_p($x);
+   };
+   if ($@) {
+      $it = $@;
+      $it =~ s/ at \S+ line \d+$\.\n//s;
+   }
+   return $it;
+}
+
+BEGIN {
+   @tests = (
+   [
+      'control',
+      sub { C4::Boolean::INVALID_BOOLEAN_STRING_EXCEPTION },
+      'The given value does not seem to be interpretable as a Boolean value',
+      undef
+
+   # False strings
+   ], [
+      '"0"',     \&f, 'OK:0', '0'
+   ], [
+      '"false"', \&f, 'OK:0', 'false'
+   ], [
+      '"off"',   \&f, 'OK:0', 'off'
+   ], [
+      '"no"',    \&f, 'OK:0', 'no'
+
+   # True strings
+   ], [
+      '"1"',     \&f, 'OK:1', '1'
+   ], [
+      '"true"',  \&f, 'OK:1', 'true'
+   ], [
+      '"on"',    \&f, 'OK:1', 'on'
+   ], [
+      '"yes"',   \&f, 'OK:1', 'yes'
+   ], [
+      '"YES"',   \&f, 'OK:1', 'YES'	# verify case insensitivity
+
+   # Illegal strings
+   ], [
+      'undef',   \&f, C4::Boolean::INVALID_BOOLEAN_STRING_EXCEPTION, undef
+   ], [
+      '"foo"',   \&f, C4::Boolean::INVALID_BOOLEAN_STRING_EXCEPTION, 'foo'
+   ],
+);
+}
+
+BEGIN { $| = 1; printf "1..%d\n", scalar(@tests); }
+END {print "not ok 1\n" unless $loaded;}
+$loaded = 1;
+
+
+# Run all tests in sequence
+for (my $i = 1; $i <= scalar @tests; $i += 1) {
+   my $test = $tests[$i - 1];
+   my($title, $f, $expected, $input) = @$test;
+   die "not ok $i (malformed test case)\n"
+      unless @$test == 4 && ref $f eq 'CODE';
+
+   my $output = &$f($input);
+   if (
+	 (!defined $output && !defined $expected)
+      || (defined $output && defined $expected && $output eq $expected)
+   ) {
+      print "ok $i - $title\n";
+   } else {
+      print "not ok $i - $title: got ",
+	    (defined $output? "\"$output\"": 'undef'),
+	    ', expected ',
+	    (defined $expected? "\"$expected\"": 'undef'),
+	    "\n";
+   }
+}
+
+
+
+
+