1 files changed, 39 insertions, 0 deletions
diff --git a/internal/provider/forwarder_test.go b/internal/provider/forwarder_test.go
new file mode 100644
index 0000000..2e9b4a1
--- /dev/null
+++ b/internal/provider/forwarder_test.go
@@ -0,0 +1,39 @@
+package provider
+
+import (
+	"encoding/json"
+	"testing"
+
+	"aigw/internal/domain"
+)
+
+func TestRewriteRequestForcesOpenAIStreamUsage(t *testing.T) {
+	result, err := rewriteRequest([]byte(`{"model":"public/model","stream":true,"stream_options":{"other":true}}`), "upstream/model", domain.ProtocolOpenAI)
+	if err != nil {
+		t.Fatal(err)
+	}
+	var body struct {
+		Model         string         `json:"model"`
+		StreamOptions map[string]any `json:"stream_options"`
+	}
+	if err := json.Unmarshal(result, &body); err != nil {
+		t.Fatal(err)
+	}
+	if body.Model != "upstream/model" || body.StreamOptions["include_usage"] != true || body.StreamOptions["other"] != true {
+		t.Fatalf("unexpected rewritten body: %s", result)
+	}
+}
+
+func TestRewriteRequestDoesNotAddStreamOptionsToAnthropic(t *testing.T) {
+	result, err := rewriteRequest([]byte(`{"model":"public/model","stream":true}`), "upstream/model", domain.ProtocolAnthropic)
+	if err != nil {
+		t.Fatal(err)
+	}
+	var body map[string]json.RawMessage
+	if err := json.Unmarshal(result, &body); err != nil {
+		t.Fatal(err)
+	}
+	if _, exists := body["stream_options"]; exists {
+		t.Fatalf("unexpected OpenAI stream options in Anthropic request: %s", result)
+	}
+}