Add by-id mount directory

mount_test.go

@@ -70,3 +70,26 @@ func TestFileNodeUnknownSizeDoesNotAdvertiseZeroLength(t *testing.T) {
 		t.Fatal("expected unknown size before download")
 	}
 }
+
+func TestBuildMountTreeAddsByIDDirectory(t *testing.T) {
+	items := []SearchItem{{
+		ID:   "item-1",
+		Name: "Invoice",
+		Attachments: []ItemAttachment{
+			{ID: "att-1", Name: "original.pdf"},
+			{ID: "att-2", Name: "extra.txt"},
+			{ID: "att-3", Name: "scan.pdf"},
+		},
+	}}
+
+	root := buildMountTree(context.Background(), &DocspellClient{}, items)
+	byID, ok := root.children["by-id"].(*dirNode)
+	if !ok {
+		t.Fatalf("expected by-id directory, got %#v", root.children)
+	}
+	for _, name := range []string{"item-1.pdf", "item-1-2.txt", "item-1-3.pdf"} {
+		if _, ok := byID.children[name].(*fileNode); !ok {
+			t.Fatalf("expected %s in by-id, got %#v", name, byID.children)
+		}
+	}
+}