Write out requirements.lock for APIVersion1 Charts

This keeps the on-disk format consistent after `helm dependency update`
of an APIVersion1 Chart.

Signed-off-by: Paul "Hampy" Hampson <p_hampson@wargaming.net>

pkg/downloader/manager.go

@@ -163,7 +163,7 @@ func (m *Manager) Update() error {
 	}
 
 	// Finally, we need to write the lockfile.
-	return writeLock(m.ChartPath, lock)
+	return writeLock(m.ChartPath, lock, c.Metadata.APIVersion == chart.APIVersionV1)
 }
 
 func (m *Manager) loadChartDir() (*chart.Chart, error) {
@@ -634,12 +634,16 @@ func (m *Manager) loadChartRepositories() (map[string]*repo.ChartRepository, err
 }
 
 // writeLock writes a lockfile to disk
-func writeLock(chartpath string, lock *chart.Lock) error {
+func writeLock(chartpath string, lock *chart.Lock, legacyLockfile bool) error {
 	data, err := yaml.Marshal(lock)
 	if err != nil {
 		return err
 	}
-	dest := filepath.Join(chartpath, "Chart.lock")
+	lockfileName := "Chart.lock"
+	if legacyLockfile {
+		lockfileName = "requirements.lock"
+	}
+	dest := filepath.Join(chartpath, lockfileName)
 	return ioutil.WriteFile(dest, data, 0644)
 }