X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=dgit.git;a=blobdiff_plain;f=git-debrebase;h=c273976cc3448885e834b2e9c269778114d6d7dd;hp=8fa5adb73b34f29054f4bd043551e3143f1a724a;hb=e66c2cf3f7182a3e6f52945636a807ed4a959d5b;hpb=d806e898308acbaca5685a4dec6688c0164ea642

diff --git a/git-debrebase b/git-debrebase
index 8fa5adb7..c273976c 100755
--- a/git-debrebase
+++ b/git-debrebase
@@ -187,8 +187,12 @@ sub get_tree ($) {
     # tree object name => ([ $name, $info ], ...)
     # where $name is the sort key, ie has / at end for subtrees
     # $info is the LHS from git-ls-tree (<mode> <type> <hash>)
-    # will crash if $x does not exist, so don't do that
+    # will crash if $x does not exist, so don't do that;
+    # instead pass '' to get ().
     my ($x) = @_;
+
+    return () if !length $x;
+
     our (@get_tree_memo, %get_tree_memo);
     my $memo = $get_tree_memo{$x};
     return @$memo if $memo;
@@ -245,70 +249,75 @@ sub trees_diff_walk ($$$;$) {
 
 sub get_differs ($$) {
     my ($x,$y) = @_;
-    # This resembles quiltify_trees_differ, in dgit, a bit.
+    # This does a similar job to quiltify_trees_differ, in dgit, a bit.
     # But we don't care about modes, or dpkg-source-unrepresentable
     # changes, and we don't need the plethora of different modes.
     # Conversely we need to distinguish different kinds of changes to
     # debian/ and debian/patches/.
+    # Also, here we have, and want to use, trees_diff_walk, because
+    # we may be calling this an awful lot and we want it to be fast.
 
     my $differs = 0;
+    my @debian_info;
 
-    my $rundiff = sub {
-	my ($opts, $limits, $fn) = @_;
-	my @cmd = (@git, qw(diff-tree -z --no-renames));
-	push @cmd, @$opts;
-	push @cmd, "$_:" foreach $x, $y;
-	push @cmd, '--', @$limits;
-	my $diffs = cmdoutput @cmd;
-	foreach (split /\0/, $diffs) { $fn->(); }
-    };
+    no warnings qw(exiting);
 
-    $rundiff->([qw(--name-only)], [], sub {
-        $differs |= $_ eq 'debian' ? DS_DEB : D_UPS;
-    });
+    my $plain = sub { $_[0] =~ m{^(100|0*)644 blob }s; };
 
-    if ($differs & DS_DEB) {
-	$differs &= ~DS_DEB;
-	$rundiff->([qw(--name-only -r)], [qw(debian)], sub {
-            $differs |=
-		m{^debian/patches/}      ? D_PAT_OTH  :
-		$_ eq 'debian/changelog' ? D_DEB_CLOG :
-		                           D_DEB_OTH;
-	});
-	die "mysterious debian changes $x..$y"
-	    unless $differs & (D_PAT_OTH|DS_DEB);
-    }
-
-    if ($differs & D_PAT_OTH) {
-	my $mode;
-	$differs &= ~D_PAT_OTH;
-	my $pat_oth = sub {
-	    $differs |= D_PAT_OTH;
-	    no warnings qw(exiting);  last;
-	};
-	$rundiff->([qw(--name-status -r)], [qw(debian/patches/)], sub {
-            no warnings qw(exiting);
-            if (!defined $mode) {
-		$mode = $_;  next;
+    trees_diff_walk "$x:", "$y:", sub {
+	my ($n,$ix,$iy) = @_;
+
+	# analyse difference at the toplevel
+
+	if ($n ne 'debian/') {
+	    $differs |= D_UPS;
+	    next;
+	}
+	if ($n eq 'debian') {
+	    # one side has a non-tree for ./debian !
+	    $differs |= D_DEB_OTH;
+	    next;
+	}
+
+	my $xd = $ix && "$x:debian";
+	my $yd = $iy && "$y:debian";
+	trees_diff_walk $xd, $yd, sub {
+	    my ($n,$ix,$iy) = @_;
+	    
+	    # analyse difference in debian/
+
+	    if ($n eq 'changelog' && (!$ix || $plain->($ix))
+                                  &&          $plain->($iy) ) {
+		$differs |= D_DEB_CLOG;
+		next;
 	    }
-	    die unless s{^debian/patches/}{};
-	    my $ok;
-	    if ($mode eq 'A' && !m/\.series$/s) {
-		$ok = 1;
-	    } elsif ($mode eq 'M' && $_ eq 'series') {
-		my $x_s = (git_cat_file "$x:debian/patches/series", 'blob');
-		my $y_s = (git_cat_file "$y:debian/patches/series", 'blob');
-		chomp $x_s;  $x_s .= "\n";
-		$ok = $x_s eq substr($y_s, 0, length $x_s);
-	    } else {
-		# nope
+	    if ($n ne 'patches/') {
+		$differs |= D_DEB_OTH;
+		next;
 	    }
-	    $mode = undef;
-	    $differs |= $ok ? D_PAT_ADD : D_PAT_OTH;
-        });
-	die "mysterious debian/patches changes $x..$y"
-	    unless $differs & (D_PAT_ADD|D_PAT_OTH);
-    }
+
+	    my $xp = $ix && "$xd/patches";
+	    my $yp = $iy && "$yd/patches";
+	    trees_diff_walk $xp, $yp, sub {
+		my ($n,$ix,$iy) = @_;
+
+		# analyse difference in debian/patches
+
+		my $ok;
+		if ($n !~ m/\.series$/s && !$ix && $plain->($iy)) {
+		    $ok = 1;
+		} elsif ($n eq 'series' && $plain->($ix) && $plain->($iy)) {
+		    my $x_s = (git_cat_file "$xp/series", 'blob');
+		    my $y_s = (git_cat_file "$yp/series", 'blob');
+		    chomp $x_s;  $x_s .= "\n";
+		    $ok = $x_s eq substr($y_s, 0, length $x_s);
+		} else {
+		    # nope
+		}
+		$differs |= $ok ? D_PAT_ADD : D_PAT_OTH;
+	    };    
+	};
+    };
 
     printdebug sprintf "get_differs %s %s = %#x\n", $x, $y, $differs;
 
@@ -2266,7 +2275,10 @@ sub cmd_stitch () {
     badusage "no arguments allowed" if @ARGV;
     do_stitch $prose, 0;
 }
-sub cmd_prepush () { cmd_stitch(); }
+sub cmd_prepush () {
+    $opt_noop_ok = 1;
+    cmd_stitch();
+}
 
 sub cmd_quick () {
     badusage "no arguments allowed" if @ARGV;