[release/v1.9.x] fix: align index loading with upstream Helm v4

internal/helm/chart/dependency_manager.go

@@ -153,11 +153,15 @@ func (dm *DependencyManager) build(ctx context.Context, ref Reference, c *helmch
 		sem := semaphore.NewWeighted(current)
 		c := &chartWithLock{Chart: c}
 		for name, dep := range deps {
-			name, dep := name, dep
 			if err := sem.Acquire(groupCtx, 1); err != nil {
 				return err
 			}
 			group.Go(func() (err error) {
+				defer func() {
+					if r := recover(); r != nil {
+						err = fmt.Errorf("failed to add dependency '%s': %v", name, r)
+					}
+				}()
 				defer sem.Release(1)
 				if isLocalDep(dep) {
 					localRef, ok := ref.(LocalReference)

internal/helm/chart/dependency_manager_test.go

@@ -281,6 +281,20 @@ func TestDependencyManager_build(t *testing.T) {
 	}
 }
 
+func TestDependencyManager_build_PanicRecovery(t *testing.T) {
+	g := NewWithT(t)
+
+	dm := NewDependencyManager(WithDownloaderCallback(func(url string) (repository.Downloader, error) {
+		panic("downloader callback error")
+	}))
+	err := dm.build(context.TODO(), LocalReference{}, &helmchart.Chart{}, map[string]*helmchart.Dependency{
+		"example": {Repository: "https://example.com"},
+	})
+	g.Expect(err).To(HaveOccurred())
+	g.Expect(err.Error()).To(ContainSubstring("failed to add dependency 'example'"))
+	g.Expect(err.Error()).To(ContainSubstring("downloader callback error"))
+}
+
 func TestDependencyManager_addLocalDependency(t *testing.T) {
 	tests := []struct {
 		name      string

internal/helm/repository/chart_repository.go

@@ -90,6 +90,7 @@ func IndexFromBytes(b []byte) (*repo.IndexFile, error) {
 	for name, cvs := range i.Entries {
 		for idx := len(cvs) - 1; idx >= 0; idx-- {
 			if cvs[idx] == nil {
+				cvs = append(cvs[:idx], cvs[idx+1:]...)
 				continue
 			}
 			// When metadata section missing, initialize with no data

internal/helm/repository/chart_repository_test.go

@@ -828,6 +828,22 @@ entries:
       home: https://github.com/something/else
       digest: "sha256:1234567890abcdef"
 `
+var indexWithEmptyEntries = `
+apiVersion: v1
+entries:
+  nginx:
+    - null
+    - urls:
+        - https://charts.helm.sh/stable/nginx-0.2.0.tgz
+      name: nginx
+      description: string
+      version: 0.2.0
+      home: https://github.com/something/else
+      digest: "sha256:1234567890abcdef"
+    - null
+  alpine:
+    - null
+`
 var indexWithLastVersionInvalid = `
 apiVersion: v1
 entries:
@@ -862,6 +878,10 @@ func TestIndexFromBytes_InvalidEntries(t *testing.T) {
 			source: "indexWithLastVersionInvalid",
 			data:   indexWithLastVersionInvalid,
 		},
+		{
+			source: "indexWithEmptyEntries",
+			data:   indexWithEmptyEntries,
+		},
 	}
 	for _, tc := range tests {
 		t.Run(tc.source, func(t *testing.T) {
@@ -874,6 +894,10 @@ func TestIndexFromBytes_InvalidEntries(t *testing.T) {
 				t.Error("expected one chart version not to be filtered out")
 			}
 			for _, v := range cvs {
+				if v == nil {
+					t.Error("empty entry was not filtered out")
+					continue
+				}
 				if v.Version == "0..1.0" {
 					t.Error("malformed version was not filtered out")
 				}