chore(trees): removed TreeConfiguration interface

We don't need an interface (yet), since there is only one
implementation. A client (user) of the package can easily add its
own interface as necessary.

trees/treeconfig.go

@@ -7,15 +7,6 @@ import (
 	"github.com/relab/hotstuff"
 )
 
-// TreeConfiguration is an abstraction for a tree communication model.
-type TreeConfiguration interface {
-	InitializeWithPIDs(treePositions []hotstuff.ID) error
-	GetTreeHeight() int
-	GetChildren() []hotstuff.ID
-	GetSubTreeNodes() []hotstuff.ID
-	GetParent() (hotstuff.ID, bool)
-}
-
 // Tree implements a fault free tree configuration.
 type Tree struct {
 	id                hotstuff.ID
@@ -26,8 +17,8 @@ type Tree struct {
 	branchFactor      int
 }
 
-// CreateTree Creates the tree configuration, currently only fault free tree configuration is supported.
-func CreateTree(configurationSize int, myID hotstuff.ID, bf int) TreeConfiguration {
+// CreateTree creates the tree configuration, currently only fault free tree configuration is supported.
+func CreateTree(configurationSize int, myID hotstuff.ID, bf int) *Tree {
 	if configurationSize <= 0 {
 		return nil
 	}

trees/treeconfig_test.go

@@ -126,17 +126,16 @@ func TestTreeAPIWithInitializeWithPIDs(t *testing.T) {
 				t.Errorf("Expected %d, got %d", test.parent, parent)
 			}
 		}
-		treeConfig := tree.(*Tree)
-		if treeConfig.IsRoot(test.id) != test.isRoot {
-			t.Errorf("Expected %t, got %t", test.isRoot, treeConfig.IsRoot(test.id))
+		if tree.IsRoot(test.id) != test.isRoot {
+			t.Errorf("Expected %t, got %t", test.isRoot, tree.IsRoot(test.id))
 		}
-		if treeConfig.GetHeight() != test.replicaHeight {
-			t.Errorf("Expected %d, got %d", test.replicaHeight, treeConfig.GetHeight())
+		if tree.GetHeight() != test.replicaHeight {
+			t.Errorf("Expected %d, got %d", test.replicaHeight, tree.GetHeight())
 		}
-		gotPeers := treeConfig.GetPeers(test.id)
+		gotPeers := tree.GetPeers(test.id)
 		sort.Slice(gotPeers, func(i, j int) bool { return gotPeers[i] < gotPeers[j] })
 		if len(gotPeers) != len(test.peers) || !slices.Equal(gotPeers, test.peers) {
-			t.Errorf("Expected %v, got %v", test.peers, treeConfig.GetPeers(test.id))
+			t.Errorf("Expected %v, got %v", test.peers, tree.GetPeers(test.id))
 		}
 	}
 }