make gerrit-bot pass the branch name to sanitize-commit

guessing the target branch with the help of git-merge-base is unreliable
when the user does a cross-branch push or the commit has simply an old
base. therefore, explicitly pass in the branch if we already know it,
which is the case on the server.

Fixes: QTQAINFRA-3322
Started-by: Daniel Smith <daniel.smith@qt.io>
Change-Id: I5fd1e827b9e169f4aa2eb3590bc4f252037d6ba0
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>
Reviewed-by: Daniel Smith <Daniel.Smith@qt.io>

2 files changed, 25 insertions, 18 deletions

diff --git a/git-hooks/gerrit-bot b/git-hooks/gerrit-bot
index 287ad98..c65f262 100755
--- a/git-hooks/gerrit-bot
+++ b/git-hooks/gerrit-bot
@@ -45,6 +45,7 @@ use Gerrit::REST;
 #     (note that these entries are NOT namespaced with the instance).
 #     The magic string @SHA1@ is replaced by the commit to be checked;
 #     @PROJ@ by the gerrit project the worker is run for.
+#     @BRANCH@ is the branch the change was submitted to.
 #     It is expected to dump a Gerrit ReviewInput JSON entity to stdout.
 #     The output from all workers is merged.
 #   excluded (optional)
@@ -194,6 +195,7 @@ sub process_commit($$$$$)
       die "workers.$worker not set.\n" if (!defined($worker));
       $worker =~ s/\@PROJ\@/$project/g;
       $worker =~ s/\@SHA1\@/$rev/g;
+      $worker =~ s/\@BRANCH\@/$branch/g;
       my $output;
       open VERDICT, $worker." 2>&1 |" or die "cannot run worker '$w': ".$!;
       {
diff --git a/git-hooks/sanitize-commit b/git-hooks/sanitize-commit
index 020fb94..724b483 100755
--- a/git-hooks/sanitize-commit
+++ b/git-hooks/sanitize-commit
@@ -13,16 +13,17 @@ use Config;
 use Cwd;
 use Encode;
 use File::Spec qw(path);
-use List::Util qw(first);
+use List::Util qw(first any);
 
-if ($#ARGV < 0 or $#ARGV > 2 or ($#ARGV >= 1 && $ARGV[1] !~ /^(easy|strict|gerrit-rest)$/)) {
-    print STDERR "Usage: $0 <sha1> [{easy|strict|gerrit-rest} [instance]]\n";
+if ($#ARGV < 0 or $#ARGV > 3 or ($#ARGV >= 1 && $ARGV[1] !~ /^(easy|strict|gerrit-rest)$/)) {
+    print STDERR "Usage: $0 <sha1> [{easy|strict|gerrit-rest} [<instance> [<branch>]]]\n";
     exit 2;
 }
 my $sha1 = $ARGV[0];
 my $gerrit_rest = ($#ARGV >= 1 && $ARGV[1] eq "gerrit-rest");
 my $strict = $gerrit_rest || ($#ARGV >= 1 && $ARGV[1] eq "strict");
-my $instance = ($#ARGV == 2) ? $ARGV[2] : "default";
+my $instance = ($#ARGV >= 2) ? $ARGV[2] : "default";
+my $target = $#ARGV == 3 && $ARGV[3];
 
 my $repo = getcwd();
 $repo =~ s,/?\.git$,,;
@@ -336,20 +337,24 @@ my $handleLts = 0;
 my $ltsForSha1 = '';
 if ($foundDev && $foundLts) {
     $handleLts = 1;
-    my $refPfx = ($seenOrigin ? "refs/remotes/origin" : "refs/heads");
-    chomp(my $sha1Base = `git merge-base $sha1 $refPfx/dev`);
-    foreach my $lts (@LTS) {
-        next if (!defined($nonDevHeads{$lts}));
-        my $key = "cached-lts-$lts-fork";
-        $key =~ s/\./-/g;  # so the dot in $lts isn't a section name boundary in the key
-        my $diverge = $config{$key};
-        if (!$diverge) {
-            chomp($diverge = `git merge-base $refPfx/dev $refPfx/$lts`);
-            system("git config sanity.$instance.$key $diverge");
-        }
-        if ($sha1Base eq $diverge) {
-            $ltsForSha1 = $lts;
-            last;
+    if (defined($target)) {
+        $ltsForSha1 = $1 if ($target =~ /^(\d+\.\d+)/ && any { $1 eq $_ } @LTS);
+    } else {
+        my $refPfx = ($seenOrigin ? "refs/remotes/origin" : "refs/heads");
+        chomp(my $sha1Base = `git merge-base $sha1 $refPfx/dev`);
+        foreach my $lts (@LTS) {
+            next if (!defined($nonDevHeads{$lts}));
+            my $key = "cached-lts-$lts-fork";
+            $key =~ s/\./-/g;  # so the dot in $lts isn't a section name boundary in the key
+            my $diverge = $config{$key};
+            if (!$diverge) {
+                chomp($diverge = `git merge-base $refPfx/dev $refPfx/$lts`);
+                system("git config sanity.$instance.$key $diverge");
+            }
+            if ($sha1Base eq $diverge) {
+                $ltsForSha1 = $lts;
+                last;
+            }
         }
     }
 }