Fix dep build to be compatiable with Helm 2 when requirements use repo alias

Signed-off-by: Song Shukun <song.shukun@fujitsu.com>

pkg/downloader/manager.go

@@ -82,6 +82,19 @@ func (m *Manager) Build() error {
 
 	// Check that all of the repos we're dependent on actually exist.
 	req := c.Metadata.Dependencies
+
+	// If using apiVersion v1, calculate the hash before resolve repo names
+	// because resolveRepoNames will change req if req uses repo alias
+	// and Helm 2 calculate the digest from the original req
+	// Fix for: https://github.com/helm/helm/issues/7619
+	var v2Sum string
+	if c.Metadata.APIVersion == chart.APIVersionV1 {
+		v2Sum, err = resolver.HashV2Req(req)
+		if err != nil {
+			return errors.New("the lock file (requirements.lock) is out of sync with the dependencies file (requirements.yaml). Please update the dependencies")
+		}
+	}
+
 	if _, err := m.resolveRepoNames(req); err != nil {
 		return err
 	}
@@ -92,7 +105,7 @@ func (m *Manager) Build() error {
 		// Fix for: https://github.com/helm/helm/issues/7233
 		if c.Metadata.APIVersion == chart.APIVersionV1 {
 			log.Println("warning: a valid Helm v3 hash was not found. Checking against Helm v2 hash...")
-			if sum, err := resolver.HashV2Req(req); err != nil || sum != lock.Digest {
+			if v2Sum != lock.Digest {
 				return errors.New("the lock file (requirements.lock) is out of sync with the dependencies file (requirements.yaml). Please update the dependencies")
 			}
 		} else {