perl: Try to avoid boolean operators after predicates on error checks

Using boolean operators after predicates for error checking makes the
code flow slightly confusing, do that only after actions, to check if
they succeeded and error out otherwise.

1 files changed, 14 insertions, 7 deletions

diff --git a/scripts/dpkg-gencontrol.pl b/scripts/dpkg-gencontrol.pl
index 404f3e124..c60101395 100755
--- a/scripts/dpkg-gencontrol.pl
+++ b/scripts/dpkg-gencontrol.pl
@@ -172,7 +172,9 @@ my $pkg;
 
 if (defined($oppackage)) {
     $pkg = $control->get_pkg_by_name($oppackage);
-    defined($pkg) || error(_g('package %s not in control info'), $oppackage);
+    if (not defined $pkg) {
+        error(_g('package %s not in control info'), $oppackage)
+    }
 } else {
     my @packages = map { $_->{'Package'} } $control->get_packages();
     if (@packages == 0) {
@@ -296,10 +298,12 @@ foreach my $field (field_list_pkg_dep()) {
 }
 
 for my $f (qw(Package Version)) {
-    defined($fields->{$f}) || error(_g('missing information for output field %s'), $f);
+    error(_g('missing information for output field %s'), $f)
+        unless defined $fields->{$f};
 }
 for my $f (qw(Maintainer Description Architecture)) {
-    defined($fields->{$f}) || warning(_g('missing information for output field %s'), $f);
+    warning(_g('missing information for output field %s'), $f)
+        unless defined $fields->{$f};
 }
 $oppackage = $fields->{'Package'};
 
@@ -324,8 +328,10 @@ if ($oppackage ne $sourcepackage || $verdiff) {
 }
 
 if (!defined($substvars->get('Installed-Size'))) {
-    my $du_fh;
-    defined(my $c = open($du_fh, '-|')) || syserr(_g('cannot fork for %s'), 'du');
+    my $c = open(my $du_fh, '-|');
+    if (not defined $c) {
+        syserr(_g('cannot fork for %s'), 'du');
+    }
     if (!$c) {
         chdir("$packagebuilddir") ||
             syserr(_g("chdir for du to \`%s'"), $packagebuilddir);
@@ -337,9 +343,10 @@ if (!defined($substvars->get('Installed-Size'))) {
 	$duo .= $_;
     }
     close($du_fh);
-    $? && subprocerr(_g("du in \`%s'"), $packagebuilddir);
-    $duo =~ m/^(\d+)\s+\.$/ ||
+    subprocerr(_g("du in \`%s'"), $packagebuilddir) if $?;
+    if ($duo !~ m/^(\d+)\s+\.$/) {
         error(_g("du gave unexpected output \`%s'"), $duo);
+    }
     $substvars->set_as_used('Installed-Size', $1);
 }
 if (defined($substvars->get('Extra-Size'))) {