Snapshot channel tree maps under client lock

ui_tree_test.go

@@ -0,0 +1,22 @@
+package main
+
+import (
+	"testing"
+
+	"git.stormux.org/storm/barnard/gumble/gumble"
+)
+
+// Regression: rebuilding the channel tree ranged protocol-owned maps without
+// Client.Do while TCP handlers could add or remove users/channels.
+func TestTreeItemBuildReadsMapsUnderClientSnapshot(t *testing.T) {
+	root := &gumble.Channel{ID: 0, Users: gumble.Users{}, Children: gumble.Channels{}}
+	user := &gumble.User{Session: 1, Name: "user"}
+	child := &gumble.Channel{ID: 2, Name: "child", Users: gumble.Users{}, Children: gumble.Channels{}}
+	root.Users[user.Session] = user
+	root.Children[child.ID] = child
+	b := &Barnard{Client: &gumble.Client{Channels: gumble.Channels{0: root}}, MutedChannels: map[uint32]bool{}}
+	items := b.TreeItemBuild(TreeItem{Channel: root})
+	if len(items) != 2 {
+		t.Fatalf("got %d items", len(items))
+	}
+}