From: Ian Jackson <ijackson@chiark.greenend.org.uk>
Date: Thu, 5 Jan 2017 01:56:43 +0000 (+0000)
Subject: badcommit-fixup: seems to work
X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=dgit-junk.git;a=commitdiff_plain;h=9ce004308b98aa57822c6a052fb0d847234f050e

badcommit-fixup: seems to work
---

diff --git a/badcommit-fixup b/badcommit-fixup
index 2eeaefe..2c28e51 100755
--- a/badcommit-fixup
+++ b/badcommit-fixup
@@ -1,11 +1,20 @@
 #!/usr/bin/perl -w
 
+# usage:
+#   .../badcommit-fixup --test
+#   .../badcommit-fixup --real
+
 use strict;
 
 use POSIX;
 use IPC::Open2;
 use Data::Dumper;
 
+die unless "@ARGV" eq "--test" or "@ARGV" eq "--real";
+
+my ($modeopt) = @ARGV;
+my $real = ($modeopt eq '--real');
+
 my $gcfpid = open2 \*GCFO, \*GCFI, 'git cat-file --batch' or die $!;
 
 our %count;
@@ -117,7 +126,40 @@ foreach my $rline (split /\n/, $refs) {
 	next;
     }
     next if $rewrite eq $obj;
-    push @updates, [ $refname, $rewrite ];
+    push @updates, [ $refname, $obj, $rewrite ];
 }
 
-print Dumper(\@updates, \%count);
+open U, "|git update-ref -m 'dgit bad commit fixup' --stdin" or die $!;
+
+if ($real) {
+    print "detaching your HEAD\n" or die $!;
+    system 'git checkout --detach' and die "$! $?";
+}
+
+for my $up (@updates) {
+    my ($ref, $old, $new) = @$up;
+    my $otherref = $ref;
+    $otherref =~ s{^refs/}{};
+    if ($real) {
+	print U <<END or die $!;
+create refs/dgit-badcommit/$otherref $old
+update $ref $new $old
+END
+    } else {
+	print U <<END or die $!;
+update refs/dgit-badfixuptest/$otherref $new
+END
+    }
+}
+
+$?=0; $!=0;
+close U or die "$? $!";
+die $? if $?;
+
+print Dumper(\%count);
+
+if ($real) {
+    print "old values saved in refs/dgit-badcommit/\n" or die $!;
+} else {
+    print "testing output saved in refs/dgit-badfixuptest/\n" or die $!;
+}