add the ability to choose the working dir from different ref for the …

…decorated container

prow/apis/prowjobs/v1/types.go

@@ -546,6 +546,12 @@ type Refs struct {
 	// set, <root-dir>/src/github.com/org/repo will be
 	// used as the default.
 	PathAlias string `json:"path_alias,omitempty"`
+
+	// WorkDir defines if the location of the cloned
+	// repository will be used as the default working
+	// directory.
+	WorkDir bool `json:"workdir,omitempty"`
+
 	// CloneURI is the URI that is used to clone the
 	// repository. If unset, will default to
 	// `https://github.com/org/repo.git`.

prow/pod-utils/decorate/podspec.go

@@ -553,14 +553,23 @@ func decorate(spec *coreapi.PodSpec, pj *prowapi.ProwJob, rawEnv map[string]stri
 	spec.Volumes = append(spec.Volumes, logVolume, toolsVolume, gcsVol)
 
 	if len(refs) > 0 {
-		spec.Containers[0].WorkingDir = clone.PathForRefs(codeMount.MountPath, refs[0])
+		spec.Containers[0].WorkingDir = determineWorkDir(codeMount.MountPath, refs)
 		spec.Containers[0].VolumeMounts = append(spec.Containers[0].VolumeMounts, codeMount)
 		spec.Volumes = append(spec.Volumes, append(cloneVolumes, codeVolume)...)
 	}
 
 	return nil
 }
 
+func determineWorkDir(baseDir string, refs []prowapi.Refs) string {
+	for _, ref := range refs {
+		if ref.WorkDir {
+			return clone.PathForRefs(baseDir, ref)
+		}
+	}
+	return clone.PathForRefs(baseDir, refs[0])
+}
+
 const (
 	// RequirePassingEntries causes sidecar to return an error if any entry fails. Otherwise it exits cleanly so long as it can complete.
 	RequirePassingEntries = true