Item14237: Added support for indenting message texts

Useful for debugging/tracing when deep recursion takes place and it is
very helpful seeing what level a message corresponds two; or how two
messages are related to each other.

core/lib/Foswiki.pm

@@ -25,7 +25,8 @@ use Exporter qw(import);
 our @EXPORT_OK = qw(
   %regex urlEncode urlDecode make_params load_package load_class
   expandStandardEscapes findCaller findCallerByPrefix isTrue
-  fetchGlobal getNS
+  indentInc indentMsg
+  fetchGlobal getNS inject_code
   $TRUE $FALSE
 );
 
@@ -983,6 +984,23 @@ sub guessHomeDir {
     return File::Spec->catpath( $v, File::Spec->catdir(@d) );
 }
 
+# --- Indentet output
+
+sub indentObj {
+    state $indentObj;
+    require Foswiki::Util::IndentMsg;
+    $indentObj = Foswiki::Util::IndentMsg->new unless defined $indentObj;
+    return $indentObj;
+}
+
+sub indentInc {
+    return indentObj->incLevel;
+}
+
+sub indentMsg {
+    return indentObj->indent(@_);
+}
+
 1;
 __END__
 Foswiki - The Free and Open Source Wiki, http://foswiki.org/

core/lib/Foswiki/Util/IndentMsg.pm

@@ -0,0 +1,89 @@
+# See bottom of file for license and copyright information
+
+package Foswiki::Util::IndentMsg;
+
+=begin TML
+
+---+!! Class Foswiki::Util::IndentMsg
+
+
+
+---++ SYNOPSIS
+
+---++ DESCRIPTION
+
+=cut
+
+use Foswiki::Class;
+extends qw<Foswiki::Object>;
+with qw<Foswiki::Util::Localize>;
+
+=begin TML
+
+---++ ATTRIBUTES
+
+=cut
+
+has indentLevel => (
+    is      => 'rw',
+    default => 0,
+);
+
+has indentStr => (
+    is      => 'rw',
+    default => "    ",
+);
+
+around setLocalizeFlags => sub {
+    return clearAttributes => 0;
+};
+
+=begin TML
+
+---++ METHODS
+
+=cut
+
+sub incLevel {
+    my $this   = shift;
+    my $holder = $this->localize;
+    $this->indentLevel( $this->indentLevel + 1 );
+    return $holder;
+}
+
+sub indent {
+    my $this   = shift;
+    my $prefix = $this->indentStr x $this->indentLevel;
+    return join( "", map { $prefix . $_ } split /\n/, join( "", @_ ) );
+}
+
+around restore => sub {
+    my $orig = shift;
+    my $this = shift;
+
+    return $orig->( $this, @_ );
+};
+
+sub setLocalizableAttributes {
+    return qw<indentLevel>;
+}
+
+1;
+__END__
+Foswiki - The Free and Open Source Wiki, http://foswiki.org/
+
+Copyright (C) 2017 Foswiki Contributors. Foswiki Contributors
+are listed in the AUTHORS file in the root of this distribution.
+NOTE: Please extend that file, not this notice.
+
+This program 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. For
+more details read LICENSE in the root of this distribution.
+
+This program 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.
+
+As per the GPL, removal of this notice is prohibited.