}
sub clone : Chained('buildChain') PathPart('clone') Args(0) {
    my ($self, $c) = @_;
    my $build = $c->stash->{build};
    requireProjectOwner($c, $build->project);
    $c->stash->{template} = 'clone-build.tt';

sub clone_submit : Chained('buildChain') PathPart('clone/submit') Args(0) {
    my ($self, $c) = @_;

    my $build = $c->stash->{build};

    requireProjectOwner($c, $build->project);
    my ($nixExprPath, $nixExprInputName) = Hydra::Controller::Jobset::nixExprPathFromParams $c;
    # When the expression is in a .scm file, assume it's a Guile + Guix
    # build expression.
    my $exprType =
        $c->request->params->{"nixexprpath"} =~ /.scm$/ ? "guile" : "nix";
    my $jobName = trim $c->request->params->{"jobname"};
    error($c, "Invalid job name: $jobName") if $jobName !~ /^$jobNameRE$/;
    my $inputInfo = {};
    foreach my $param (keys %{$c->request->params}) {
        next unless $param =~ /^input-(\w+)-name$/;
        my $baseName = $1;
        my ($inputName, $inputType) =
            Hydra::Controller::Jobset::checkInput($c, $baseName);
        my $inputValue = Hydra::Controller::Jobset::checkInputValue(
            $c, $inputType, $c->request->params->{"input-$baseName-value"});
        eval {
            # !!! fetchInput can take a long time, which might cause
            # the current HTTP request to time out.  So maybe this
            # should be done asynchronously.  But then error reporting
            # becomes harder.
            my $info = fetchInput(
                $c->hydra_plugins, $c->model('DB'), $build->project, $build->jobset,
                $inputName, $inputType, $inputValue);
            push @{$$inputInfo{$inputName}}, $info if defined $info;
        };
        error($c, $@) if $@;
    }
    my ($jobs, $nixExprInput) = evalJobs($inputInfo, $exprType, $nixExprInputName, $nixExprPath);
    my $job;
    foreach my $j (@{$jobs->{job}}) {
        print STDERR $j->{jobName}, "\n";
        if ($j->{jobName} eq $jobName) {
            error($c, "Nix expression returned multiple builds for job $jobName.")
                if $job;
            $job = $j;
        }
    }
    error($c, "Nix expression did not return a job named $jobName.") unless $job;
    my %currentBuilds;
    my $newBuild = checkBuild(
        $c->model('DB'), $build->jobset,
        $inputInfo, $nixExprInput, $job, \%currentBuilds, undef, {}, $c->hydra_plugins);
    error($c, "This build has already been performed.") unless $newBuild;
    $c->flash->{successMsg} = "Build " . $newBuild->id . " added to the queue.";
    $c->res->redirect($c->uri_for($c->controller('Root')->action_for('queue')));
}

[% WRAPPER layout.tt title="Clone build ${build.id}" %]
[% PROCESS common.tt %]
[% USE HTML %]
[% edit=1 %]
<p>Cloning allows you to perform a build with modified inputs.</p>
<form action="[% c.uri_for('/build' build.id 'clone' 'submit') %]" method="post">
  <h2>Nix expression</h2>
  <p>Evaluate job <tt><input type="text" class="string"
  name="jobname" [% HTML.attributes(value => build.job.name) %]
  /></tt> in Nix expression <tt><input type="text" class="string"
  name="nixexprpath" [% HTML.attributes(value => build.nixexprpath) %]
  /></tt> in input <tt><input type="text" class="string"
  name="nixexprinput" [% HTML.attributes(value => build.nixexprinput)
  %] /></tt>.</p>
  <h2>Build inputs</h2>
  <table class="table table-condensed table-striped">
    <thead>
      <tr><th>Name</th><th>Type</th><th>Value</th></tr>
    </thead>
    <tbody>
      [% FOREACH input IN build.inputs %]
        <tr>
          <td><tt>[% input.name %]<input type="hidden" [% HTML.attributes(name => "input-$input.name-name" value => input.name) %] /></tt></td>
          <td>
            [% INCLUDE renderSelection curValue=input.type param="input-$input.name-type" options=inputTypes %]
          </td>
          <td>
            <tt><input type="text" class="string" name="input-[% input.name %]-value"
              [% IF input.type == "build" || input.type == "sysbuild" %]
                [% build = input.dependency %]
                [% HTML.attributes(value => build.project.name _ ':' _ build.jobset.name _ ':' _ build.job.name _ '[id="'_ build.id _ '"]' ) %]
              [% ELSE %]
                [% HTML.attributes(value => input.value || input.uri) %]
              [% END %] /></tt>
          </td>
        </tr>
      [% END %]
    </tbody>
  </table>
</form>
[% END %]
  <p><button type="submit"><img alt="Add" src="[% c.uri_for("/static/images/success.gif") %]" />Add to queue</button></p>

        <li><a href="[% c.uri_for('/build' build.id 'clone') %]">Clone</a></li>

    -- instantiated this build.  Needed if we want to clone this

    -- instantiated this build.  Needed if we want to reproduce this