Ignore placeholder VLESS flow values

Author: Resinat

internal/subscription/parser.go

@@ -1237,7 +1237,7 @@ func convertClashProxyToNode(proxy map[string]any) (ParsedNode, bool) {
 			"server_port": port,
 			"uuid":        uuid,
 		}
-		if flow := strings.TrimSpace(getString(proxy, "flow")); flow != "" {
+		if flow := normalizeVLESSFlow(getString(proxy, "flow")); flow != "" {
 			outbound["flow"] = flow
 		}
 		setTLSFromClash(outbound, proxy, "tls")
@@ -1771,6 +1771,18 @@ func normalizeHysteriaRate(raw string) string {
 	return value
 }
 
+func normalizeVLESSFlow(raw string) string {
+	flow := strings.TrimSpace(raw)
+	switch strings.ToLower(flow) {
+	case "", "none", "null":
+		return ""
+	case "xtls-rprx-vision":
+		return "xtls-rprx-vision"
+	default:
+		return ""
+	}
+}
+
 func normalizeShadowsocksMethod(raw string) string {
 	method := strings.TrimSpace(raw)
 	if method == "" {
@@ -3112,7 +3124,7 @@ func parseVlessURI(uri string) (ParsedNode, bool) {
 		"server_port": port,
 		"uuid":        uuid,
 	}
-	if flow := strings.TrimSpace(query.Get("flow")); flow != "" {
+	if flow := normalizeVLESSFlow(query.Get("flow")); flow != "" {
 		outbound["flow"] = flow
 	}
 

internal/subscription/parser_test.go

@@ -900,6 +900,37 @@ func TestParseGeneralSubscription_ClashJSON_VLESSRealityOpts(t *testing.T) {
 	}
 }
 
+func TestParseGeneralSubscription_ClashJSON_VLESSFlowNoneIgnored(t *testing.T) {
+	data := []byte(`{
+		"proxies": [
+			{
+				"name": "vless-none-flow",
+				"type": "vless",
+				"server": "203.0.113.20",
+				"port": 443,
+				"uuid": "11111111-2222-3333-4444-555555555556",
+				"tls": true,
+				"flow": "None",
+				"network": "tcp",
+				"servername": "example.com"
+			}
+		]
+	}`)
+
+	nodes, err := ParseGeneralSubscription(data)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(nodes) != 1 {
+		t.Fatalf("expected 1 parsed node, got %d", len(nodes))
+	}
+
+	obj := parseNodeRaw(t, nodes[0].RawOptions)
+	if _, exists := obj["flow"]; exists {
+		t.Fatalf("flow should be omitted for placeholder value, got %v", obj["flow"])
+	}
+}
+
 func TestParseGeneralSubscription_ClashJSON_VLESSWSDropsALPN(t *testing.T) {
 	data := []byte(`{
 		"proxies": [
@@ -1073,6 +1104,25 @@ vless://26a1d547-b031-4139-9fc5-6671e1d0408a@example.com:443?type=tcp&security=t
 	}
 }
 
+func TestParseGeneralSubscription_VLESSURIFlowNoneIgnored(t *testing.T) {
+	data := []byte(
+		"vless://11111111-2222-3333-4444-555555555557@example.com:443?type=tcp&security=tls&sni=example.com&flow=None",
+	)
+
+	nodes, err := ParseGeneralSubscription(data)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(nodes) != 1 {
+		t.Fatalf("expected 1 parsed node, got %d", len(nodes))
+	}
+
+	obj := parseNodeRaw(t, nodes[0].RawOptions)
+	if _, exists := obj["flow"]; exists {
+		t.Fatalf("flow should be omitted for placeholder value, got %v", obj["flow"])
+	}
+}
+
 func TestParseGeneralSubscription_VMess1URILine(t *testing.T) {
 	data := []byte(
 		"vmess1://11111111-2222-3333-4444-555555555555@example.com:443?network=ws&tls=true&ws.host=ws.example.com&path=%2Fws#VMESS1%20Node",