snapshot of https://github.com/grpc/grpc-go.git (master, 2026-09-15; blobs > 131072B omitted)

internal/xds/credentials/xds_test.go

@@ -0,0 +1,76 @@
+/*
+ *
+ * Copyright 2026 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package credentials_test
+
+import (
+	"strings"
+	"testing"
+
+	xdscreds "google.golang.org/grpc/internal/xds/credentials"
+	"google.golang.org/protobuf/types/known/anypb"
+
+	xdscredspb "github.com/envoyproxy/go-control-plane/envoy/extensions/grpc_service/channel_credentials/xds/v3"
+)
+
+const xdsCredsTypeURL = "type.googleapis.com/envoy.extensions.grpc_service.channel_credentials.xds.v3.XdsCredentials"
+
+// Tests that building xds channel credentials fails on malformed configs and
+// on missing or unsupported fallback credentials.
+func (s) TestXDSCredsBuild_Errors(t *testing.T) {
+	missingFallback, err := anypb.New(&xdscredspb.XdsCredentials{})
+	if err != nil {
+		t.Fatalf("Failed to marshal XdsCredentials: %v", err)
+	}
+	unsupportedFallback, err := anypb.New(&xdscredspb.XdsCredentials{
+		FallbackCredentials: &anypb.Any{TypeUrl: "type.googleapis.com/unknown.Credentials"},
+	})
+	if err != nil {
+		t.Fatalf("Failed to marshal XdsCredentials: %v", err)
+	}
+
+	tests := []struct {
+		name    string
+		config  *anypb.Any
+		wantErr string
+	}{
+		{
+			name:    "unmarshal_failure",
+			config:  &anypb.Any{TypeUrl: xdsCredsTypeURL, Value: []byte{0xff}},
+			wantErr: "failed to unmarshal XdsCredentials",
+		},
+		{
+			name:    "missing_fallback_credentials",
+			config:  missingFallback,
+			wantErr: "missing required fallback credentials",
+		},
+		{
+			name:    "unsupported_fallback_credentials_type",
+			config:  unsupportedFallback,
+			wantErr: "unsupported fallback credentials type",
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			_, _, err := xdscreds.GetChannelCredsBuilder(xdsCredsTypeURL)(tt.config, nil)
+			if err == nil || !strings.Contains(err.Error(), tt.wantErr) {
+				t.Fatalf("Build returned error %v, want error containing %q", err, tt.wantErr)
+			}
+		})
+	}
+}