Dgit.pm: git_cat_file: Introduce $etype parameter

No functional change for existing callers.

Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>

diff --git a/Debian/Dgit.pm b/Debian/Dgit.pm
index f299450b94eb7b52ce0fff60ec73613924f9cf92..abcf123652e6db4917b9305cbdb5245d8802499e 100644 (file)
--- a/Debian/Dgit.pm
+++ b/Debian/Dgit.pm
@@ -348,11 +348,21 @@ sub git_rev_parse ($) {
     return cmdoutput qw(git rev-parse), "$_[0]~0";
 }
 
-sub git_cat_file ($) {
-    my ($objname) = @_;
+sub git_cat_file ($;$) {
+    my ($objname, $etype) = @_;
     # => ($type, $data) or ('missing', undef)
     # in scalar context, just the data
+    # if $etype defined, dies unless type is $etype or in @$etype
     our ($gcf_pid, $gcf_i, $gcf_o);
+    my $chk = sub {
+       my ($gtype, $data) = @_;
+       if ($etype) {
+           $etype = [$etype] unless ref $etype;
+           confess "$objname expected @$etype but is $gtype"
+               unless grep { $gtype eq $_ } @$etype;
+       }
+       return ($gtype, $data);
+    };
     if (!$gcf_pid) {
        my @cmd = qw(git cat-file --batch);
        debugcmd "GCF|", @cmd;
@@ -362,13 +372,13 @@ sub git_cat_file ($) {
     print $gcf_i $objname, "\n" or die $!;
     my $x = <$gcf_o>;
     printdebug "GCF<| ", $x;
-    if ($x =~ m/ (missing)$/) { return ($1, undef); }
+    if ($x =~ m/ (missing)$/) { return $chk->($1, undef); }
     my ($type, $size) = $x =~ m/^.* (\w+) (\d+)\n/ or die "$objname ?";
     my $data;
     (read $gcf_o, $data, $size) == $size or die "$objname $!";
     $x = <$gcf_o>;
     $x eq "\n" or die "$objname ($_) $!";
-    return ($type, $data);
+    return $chk->($type, $data);
 }
 
 sub git_for_each_ref ($$;$) {