test(message): cover slack and feishu media fallbacks

pkg/channels/feishu/feishu_64.go

@@ -52,6 +52,8 @@ type FeishuChannel struct {
 
 	progress        *channels.ToolFeedbackAnimator
 	deleteMessageFn func(context.Context, string, string) error
+	sendMediaPartFn func(context.Context, string, bus.MediaPart, media.MediaStore) error
+	sendTextFn      func(context.Context, string, string) (string, error)
 }
 
 type cachedMessage struct {
@@ -78,6 +80,8 @@ func NewFeishuChannel(bc *config.Channel, cfg *config.FeishuSettings, bus *bus.M
 		client:      lark.NewClient(cfg.AppID, cfg.AppSecret.String(), opts...),
 	}
 	ch.deleteMessageFn = ch.deleteMessageAPI
+	ch.sendMediaPartFn = ch.sendMediaPart
+	ch.sendTextFn = ch.sendText
 	ch.progress = channels.NewToolFeedbackAnimator(ch.EditMessage)
 	ch.SetOwner(ch)
 	return ch, nil
@@ -500,13 +504,13 @@ func (c *FeishuChannel) SendMedia(ctx context.Context, msg bus.OutboundMediaMess
 	caption := firstMediaCaption(msg.Parts)
 	sentAny := false
 	for _, part := range msg.Parts {
-		if err := c.sendMediaPart(ctx, msg.ChatID, part, store); err != nil {
+		if err := c.sendMediaPartFn(ctx, msg.ChatID, part, store); err != nil {
 			return nil, err
 		}
 		sentAny = true
 	}
 	if sentAny && caption != "" {
-		if _, err := c.sendText(ctx, msg.ChatID, caption); err != nil {
+		if _, err := c.sendTextFn(ctx, msg.ChatID, caption); err != nil {
 			return nil, err
 		}
 	}

pkg/channels/feishu/feishu_64_test.go

@@ -9,7 +9,9 @@ import (
 
 	larkim "github.com/larksuite/oapi-sdk-go/v3/service/im/v1"
 
+	"github.com/sipeed/picoclaw/pkg/bus"
 	"github.com/sipeed/picoclaw/pkg/channels"
+	"github.com/sipeed/picoclaw/pkg/media"
 )
 
 func TestExtractContent(t *testing.T) {
@@ -319,6 +321,43 @@ func TestFinalizeTrackedToolFeedbackMessage_ClearAfterSuccessfulEdit(t *testing.
 	}
 }
 
+func TestSendMedia_SendsCaptionFallbackAfterMedia(t *testing.T) {
+	ch := &FeishuChannel{
+		BaseChannel: channels.NewBaseChannel("feishu", nil, nil, nil),
+		progress:    channels.NewToolFeedbackAnimator(nil),
+	}
+	ch.SetRunning(true)
+	ch.SetMediaStore(media.NewFileMediaStore())
+
+	var mediaOrder []string
+	var textCalls []string
+	ch.sendMediaPartFn = func(ctx context.Context, chatID string, part bus.MediaPart, store media.MediaStore) error {
+		mediaOrder = append(mediaOrder, part.Type)
+		return nil
+	}
+	ch.sendTextFn = func(ctx context.Context, chatID, text string) (string, error) {
+		textCalls = append(textCalls, chatID+"|"+text)
+		return "msg-1", nil
+	}
+
+	_, err := ch.SendMedia(context.Background(), bus.OutboundMediaMessage{
+		ChatID: "oc_123",
+		Parts: []bus.MediaPart{
+			{Type: "image", Caption: "shared caption"},
+			{Type: "file"},
+		},
+	})
+	if err != nil {
+		t.Fatalf("SendMedia() error = %v", err)
+	}
+	if len(mediaOrder) != 2 {
+		t.Fatalf("media sends = %v, want 2 sends", mediaOrder)
+	}
+	if len(textCalls) != 1 || textCalls[0] != "oc_123|shared caption" {
+		t.Fatalf("textCalls = %v, want [oc_123|shared caption]", textCalls)
+	}
+}
+
 func TestFinalizeTrackedToolFeedbackMessage_StopsTrackingBeforeEdit(t *testing.T) {
 	ch := &FeishuChannel{
 		progress: channels.NewToolFeedbackAnimator(nil),