[PATCH] avoid length in boolean context

[PATCH] avoid length in boolean context

[Eric Wong]

Perl does not currently optimize for this.

ref (from p5p):
http://mid.gmane.org/D5C27970-9176-4C7A-8B99-7D78360E67A2@pobox.com
---
 lib/PublicInbox/Feed.pm      |  2 +-
 lib/PublicInbox/Filter.pm    |  2 +-
 lib/PublicInbox/Search.pm    |  3 ++-
 lib/PublicInbox/SearchIdx.pm |  6 +++---
 lib/PublicInbox/View.pm      | 24 ++++++++++++++----------
 lib/PublicInbox/WWW.pm       |  2 +-
 public-inbox-mda             |  4 ++--
 7 files changed, 24 insertions(+), 19 deletions(-)

diff --git a/lib/PublicInbox/Feed.pm b/lib/PublicInbox/Feed.pm
index 9e56747..bc76cdc 100644
--- a/lib/PublicInbox/Feed.pm
+++ b/lib/PublicInbox/Feed.pm
@@ -216,7 +216,7 @@ sub get_feedopts {
 		close $fh;
 	}
 
-	if ($pi_config && defined $listname && length $listname) {
+	if ($pi_config && defined $listname && $listname ne '') {
 		foreach my $key (qw(address)) {
 			$rv{$key} = $pi_config->get($listname, $key) || "";
 		}
diff --git a/lib/PublicInbox/Filter.pm b/lib/PublicInbox/Filter.pm
index 0b1ec91..c0985dd 100644
--- a/lib/PublicInbox/Filter.pm
+++ b/lib/PublicInbox/Filter.pm
@@ -211,7 +211,7 @@ sub collapse {
 	$mime->header_set('Content-Type', $part->content_type);
 	$mime->body_set($part->body_raw);
 	my $cte = $part->header('Content-Transfer-Encoding');
-	if (defined($cte) && length($cte)) {
+	if (defined($cte) && $cte ne '') {
 		$mime->header_set('Content-Transfer-Encoding', $cte);
 	}
 	mark_changed($mime);
diff --git a/lib/PublicInbox/Search.pm b/lib/PublicInbox/Search.pm
index 4362a00..4b3830e 100644
--- a/lib/PublicInbox/Search.pm
+++ b/lib/PublicInbox/Search.pm
@@ -251,10 +251,11 @@ sub subject_summary {
 			last if length($new) >= $max;
 			$subj = $new;
 		}
-		if (length $subj) {
+		if ($subj ne '') {
 			my $r = scalar @subj ? ' ...' : '';
 			$subj =~ s/ \z/$r/s;
 		} else {
+			# subject has one REALLY long word, and NOT spam? wtf
 			@subj = ($l =~ /\A(.{1,72})/);
 			$subj = $subj[0] . ' ...';
 		}
diff --git a/lib/PublicInbox/SearchIdx.pm b/lib/PublicInbox/SearchIdx.pm
index 292419e..2ac53a7 100644
--- a/lib/PublicInbox/SearchIdx.pm
+++ b/lib/PublicInbox/SearchIdx.pm
@@ -74,7 +74,7 @@ sub add_message {
 
 		my $subj = $smsg->subject;
 
-		if (length $subj) {
+		if ($subj ne '') {
 			$doc->add_term(xpfx('subject') . $subj);
 
 			my $path = $self->subject_path($subj);
@@ -308,7 +308,7 @@ sub _index_sync {
 		my $git = PublicInbox::GitCatFile->new($self->{git_dir});
 
 		my $latest = $db->get_metadata('last_commit');
-		my $range = length $latest ? "$latest..$head" : $head;
+		my $range = $latest eq '' ? $head : "$latest..$head";
 		$latest = undef;
 
 		# get indexed messages
@@ -394,7 +394,7 @@ sub _read_git_config_perm {
 sub _git_config_perm {
 	my $self = shift;
 	my $perm = scalar @_ ? $_[0] : _read_git_config_perm($self);
-	return PERM_GROUP if (!defined($perm) || !length($perm));
+	return PERM_GROUP if (!defined($perm) || $perm eq '');
 	return PERM_UMASK if ($perm eq 'umask');
 	return PERM_GROUP if ($perm eq 'group');
 	if ($perm =~ /\A(?:all|world|everybody)\z/) {
diff --git a/lib/PublicInbox/View.pm b/lib/PublicInbox/View.pm
index 51fee04..cc68229 100644
--- a/lib/PublicInbox/View.pm
+++ b/lib/PublicInbox/View.pm
@@ -198,7 +198,7 @@ sub index_walk {
 	$s =~ s/^\s*$//sgm;
 	$s =~ s/\s+\z//s;
 
-	if (length $s) {
+	if ($s ne '') {
 		# kill per-line trailing whitespace
 		$s =~ s/[ \t]+$//sgm;
 		$s .= "\n" unless $s =~ /\n\z/s;
@@ -352,7 +352,7 @@ sub headers_to_html_header {
 	my $mid_href = $mid->as_href;
 	foreach my $h (qw(From To Cc Subject Date)) {
 		my $v = $mime->header($h);
-		defined($v) && length($v) or next;
+		defined($v) && ($v ne '') or next;
 		$v = PublicInbox::Hval->new_oneline($v);
 
 		if ($h eq 'From') {
@@ -414,7 +414,7 @@ sub html_footer {
 
 	foreach my $h (qw(From To Cc)) {
 		my $v = $mime->header($h);
-		defined($v) && length($v) or next;
+		defined($v) && ($v ne '') or next;
 		my @addrs = Email::Address->parse($v);
 		foreach my $recip (@addrs) {
 			my $address = $recip->address;
@@ -439,9 +439,9 @@ sub html_footer {
 	my $srch = $ctx->{srch} if $ctx;
 	my $idx = $standalone ? " <a\nhref=\"../../\">index</a>" : '';
 	if ($idx && $srch) {
-		$irt = $mime->header('In-Reply-To') || '';
 		$mid = mid_compress(mid_clean($mid));
-		my $t_anchor = length $irt ? T_ANCHOR : '';
+		my $t_anchor = defined $irt ? T_ANCHOR : '';
+		$irt = $mime->header('In-Reply-To');
 		$idx = " <a\nhref=\"../../t/$mid/$t_anchor\">".
 		       "threadlink</a>$idx";
 		my $res = $srch->get_followups($mid);
@@ -458,7 +458,7 @@ sub html_footer {
 		} else {
 			$idx .= "\n(no followups, yet)\n";
 		}
-		if ($irt) {
+		if (defined $irt) {
 			$irt = PublicInbox::Hval->new_msgid($irt);
 			$irt = $irt->as_href;
 			$irt = "<a\nhref=\"../$irt/\">parent</a> ";
@@ -499,10 +499,14 @@ sub simple_dump {
 			my $mid = $x->header('Message-ID');
 			my $pfx = '  ' x $level;
 			$$dst .= $pfx;
+
+			# Subject is never undef, this mail was loaded from
+			# our Xapian which would've resulted in '' if it were
+			# really missing (and Filter rejects empty subjects)
 			my $s = $x->header('Subject');
 			my $h = $root->[2]->subject_path($s);
 			if ($root->[1]->{$h}) {
-				$s = '';
+				$s = undef;
 			} else {
 				$root->[1]->{$h} = 1;
 				$s = PublicInbox::Hval->new($s);
@@ -514,11 +518,11 @@ sub simple_dump {
 			$m = '../' . $m->as_href . '/';
 			$f = $f->as_html;
 			$d = $d->as_html . ' UTC';
-			if (length($s) == 0) {
-				$$dst .= "` <a\nhref=\"$m\">$f @ $d</a>\n";
-			} else {
+			if (defined $s) {
 				$$dst .= "` <a\nhref=\"$m\">$s</a>\n" .
 				     "$pfx  by $f @ $d\n";
+			} else {
+				$$dst .= "` <a\nhref=\"$m\">$f @ $d</a>\n";
 			}
 		}
 	}
diff --git a/lib/PublicInbox/WWW.pm b/lib/PublicInbox/WWW.pm
index 8058f3e..a01271b 100644
--- a/lib/PublicInbox/WWW.pm
+++ b/lib/PublicInbox/WWW.pm
@@ -249,7 +249,7 @@ sub do_redirect {
 sub ctx_get {
 	my ($ctx, $key) = @_;
 	my $val = $ctx->{$key};
-	(defined $val && length $val) or die "BUG: bad ctx, $key unusable\n";
+	(defined $val && $val ne '') or die "BUG: bad ctx, $key unusable\n";
 	$val;
 }
 
diff --git a/public-inbox-mda b/public-inbox-mda
index c4822b6..b1f33af 100755
--- a/public-inbox-mda
+++ b/public-inbox-mda
@@ -64,7 +64,7 @@ if (PublicInbox::MDA->precheck($filter, $dst->{address}) &&
 } else {
 	# Ensure emergency spam gets spamassassin headers.
 	# This makes it easier to prioritize obvious spam from less obvious
-	if (defined($filtered) && length($filtered)) {
+	if (defined($filtered) && $filtered ne '') {
 		my $drop = Email::MIME->new(\$filtered);
 		$filtered = undef;
 		$filter->simple($drop);
@@ -82,7 +82,7 @@ sub do_spamc {
 		run([qw/spamc -E --headers/], \$orig, $out);
 	};
 
-	return ($@ || $? || !defined($$out) || length($$out) == 0) ? 0 : 1;
+	return ($@ || $? || !defined($$out) || $$out eq '') ? 0 : 1;
 }
 
 sub search_index_sync {
-- 
EW