SelfLoader can lose $@ in AUTOLOAD() (from Nicholas Clark

<nick@ccl4.org>)

p4raw-id: //depot/perl@6183

diff --git a/MANIFEST b/MANIFEST
index e671b82..68e6ec4 100644 (file)
--- a/MANIFEST
+++ b/MANIFEST
@@ -1365,6 +1365,7 @@ t/lib/safe2.t             See if Safe works
 t/lib/sdbm.t           See if SDBM_File works
 t/lib/searchdict.t     See if Search::Dict works
 t/lib/selectsaver.t    See if SelectSaver works
+t/lib/selfloader.t     See if SelfLoader works
 t/lib/socket.t         See if Socket works
 t/lib/soundex.t                See if Soundex works
 t/lib/symbol.t         See if Symbol works

diff --git a/lib/SelfLoader.pm b/lib/SelfLoader.pm
index 99372f2..3b9c52d 100644 (file)
--- a/lib/SelfLoader.pm
+++ b/lib/SelfLoader.pm
@@ -3,7 +3,7 @@ package SelfLoader;
 require Exporter;
 @ISA = qw(Exporter);
 @EXPORT = qw(AUTOLOAD);
-$VERSION = "1.0901";
+$VERSION = "1.0902";
 sub Version {$VERSION}
 $DEBUG = 0;
 
@@ -20,6 +20,7 @@ sub croak { require Carp; goto &Carp::croak }
 AUTOLOAD {
     print STDERR "SelfLoader::AUTOLOAD for $AUTOLOAD\n" if $DEBUG;
     my $SL_code = $Cache{$AUTOLOAD};
+    my $save = $@; # evals in both AUTOLOAD and _load_stubs can corrupt $@
     unless ($SL_code) {
         # Maybe this pack had stubs before __DATA__, and never initialized.
         # Or, this maybe an automatic DESTROY method call when none exists.
@@ -31,11 +32,13 @@ AUTOLOAD {
         croak "Undefined subroutine $AUTOLOAD" unless $SL_code;
     }
     print STDERR "SelfLoader::AUTOLOAD eval: $SL_code\n" if $DEBUG;
+
     eval $SL_code;
     if ($@) {
         $@ =~ s/ at .*\n//;
         croak $@;
     }
+    $@ = $save;
     defined(&$AUTOLOAD) || die "SelfLoader inconsistency error";
     delete $Cache{$AUTOLOAD};
     goto &$AUTOLOAD

diff --git a/t/lib/selfloader.t b/t/lib/selfloader.t
new file mode 100755 (executable)
index 0000000..9c585a5
--- /dev/null
+++ b/t/lib/selfloader.t
@@ -0,0 +1,198 @@
+#!./perl
+
+BEGIN {
+    chdir 't' if -d 't';
+    $dir = "self-$$";
+    unshift @INC, ("./$dir", "../lib");
+
+    print "1..19\n";
+
+    # First we must set up some selfloader files
+    mkdir $dir, 0755            or die "Can't mkdir $dir: $!";
+
+    open(FOO, ">$dir/Foo.pm") or die;
+    print FOO <<'EOT';
+package Foo;
+use SelfLoader;
+
+sub new { bless {}, shift }
+sub foo;
+sub bar;
+sub bazmarkhianish;
+sub a;
+sub never;    # declared but definition should never be read
+1;
+__DATA__
+
+sub foo { shift; shift || "foo" };
+
+sub bar { shift; shift || "bar" }
+
+sub bazmarkhianish { shift; shift || "baz" }
+
+package sheep;
+sub bleat { shift; shift || "baa" }
+
+__END__
+sub never { die "D'oh" }
+EOT
+
+    close(FOO);
+
+    open(BAR, ">$dir/Bar.pm") or die;
+    print BAR <<'EOT';
+package Bar;
+use SelfLoader;
+
+@ISA = 'Baz';
+
+sub new { bless {}, shift }
+sub a;
+
+1;
+__DATA__
+
+sub a { 'a Bar'; }
+sub b { 'b Bar' }
+
+__END__ DATA
+sub never { die "D'oh" }
+EOT
+
+    close(BAR);
+};
+
+
+package Baz;
+
+sub a { 'a Baz' }
+sub b { 'b Baz' }
+sub c { 'c Baz' }
+
+
+package main;
+use Foo;
+use Bar;
+
+$foo = new Foo;
+
+print "not " unless $foo->foo eq 'foo';  # selfloaded first time
+print "ok 1\n";
+
+print "not " unless $foo->foo eq 'foo';  # regular call
+print "ok 2\n";
+
+# Try an undefined method
+eval {
+    $foo->will_fail;
+};
+if ($@ =~ /^Undefined subroutine/) {
+    print "ok 3\n";
+} else {
+    print "not ok 3 $@\n";
+}
+
+# Used to be trouble with this
+eval {
+    my $foo = new Foo;
+    die "oops";
+};
+if ($@ =~ /oops/) {
+    print "ok 4\n";
+} else {
+    print "not ok 4 $@\n";
+}
+
+# Pass regular expression variable to autoloaded function.  This used
+# to go wrong in AutoLoader because it used regular expressions to generate
+# autoloaded filename.
+"foo" =~ /(\w+)/;
+print "not " unless $1 eq 'foo';
+print "ok 5\n";
+
+print "not " unless $foo->bar($1) eq 'foo';
+print "ok 6\n";
+
+print "not " unless $foo->bar($1) eq 'foo';
+print "ok 7\n";
+
+print "not " unless $foo->bazmarkhianish($1) eq 'foo';
+print "ok 8\n";
+
+print "not " unless $foo->bazmarkhianish($1) eq 'foo';
+print "ok 9\n";
+
+# Check nested packages inside __DATA__
+print "not " unless sheep::bleat()  eq 'baa';
+print "ok 10\n";
+
+# Now check inheritance:
+
+$bar = new Bar;
+
+# Before anything is SelfLoaded there is no declaration of Foo::b so we should
+# get Baz::b
+print "not " unless $bar->b() eq 'b Baz';
+print "ok 11\n";
+
+# There is no Bar::c so we should get Baz::c
+print "not " unless $bar->c() eq 'c Baz';
+print "ok 12\n";
+
+# This selfloads Bar::a because it is stubbed. It also stubs Bar::b as a side
+# effect
+print "not " unless $bar->a() eq 'a Bar';
+print "ok 13\n";
+
+print "not " unless $bar->b() eq 'b Bar';
+print "ok 14\n";
+
+print "not " unless $bar->c() eq 'c Baz';
+print "ok 15\n";
+
+
+
+# Check that __END__ is honoured
+# Try an subroutine that should never be noticed by selfloader
+eval {
+    $foo->never;
+};
+if ($@ =~ /^Undefined subroutine/) {
+    print "ok 16\n";
+} else {
+    print "not ok 16 $@\n";
+}
+
+# Try to read from the data file handle
+my $foodata = <Foo::DATA>;
+if (defined $foodata) {
+    print "not ok 17 # $foodata\n";
+} else {
+    print "ok 17\n";
+}
+
+# Check that __END__ DATA is honoured
+# Try an subroutine that should never be noticed by selfloader
+eval {
+    $bar->never;
+};
+if ($@ =~ /^Undefined subroutine/) {
+    print "ok 18\n";
+} else {
+    print "not ok 18 $@\n";
+}
+
+# Try to read from the data file handle
+my $bardata = <Bar::DATA>;
+if ($bardata ne "sub never { die \"D'oh\" }\n") {
+    print "not ok 19 # $bardata\n";
+} else {
+    print "ok 19\n";
+}
+
+# cleanup
+END {
+return unless $dir && -d $dir;
+unlink "$dir/Foo.pm", "$dir/Bar.pm";
+rmdir "$dir";
+}