test: added unit tests for serialization

tests/seralization_test.go

@@ -0,0 +1,126 @@
+package huffman
+
+import (
+	"github.com/absolutezero000/encoding/huffman"
+	"testing"
+)
+
+func checkIfEqual(root1 *huffman.Node, root2 *huffman.Node) bool {
+	if root1 == nil && root2 == nil {
+		return true
+	}
+	if root1 == nil || root2 == nil {
+		return false
+	}
+	return root1.Char == root2.Char && root1.Freq == root2.Freq && checkIfEqual(root1.Left, root2.Left) && checkIfEqual(root1.Right, root2.Right)
+}
+func TestSeralization(t *testing.T) {
+	testCases := []struct {
+		name string
+		root *huffman.Node
+	}{
+		{
+			name: "simple tree with two characters",
+			root: &huffman.Node{
+				Char: 'a',
+				Freq: 5,
+				Left: &huffman.Node{
+					Char:  'b',
+					Freq:  2,
+					Left:  nil,
+					Right: nil,
+				},
+				Right: &huffman.Node{
+					Char:  'c',
+					Freq:  3,
+					Left:  nil,
+					Right: nil,
+				},
+			},
+		},
+		{
+			name: "more complex tree",
+			root: &huffman.Node{
+				Char: 0,
+				Freq: 10,
+				Left: &huffman.Node{
+					Char:  'd',
+					Freq:  4,
+					Left:  nil,
+					Right: nil,
+				},
+				Right: &huffman.Node{
+					Char: 0,
+					Freq: 6,
+					Left: &huffman.Node{
+						Char:  'e',
+						Freq:  3,
+						Left:  nil,
+						Right: nil,
+					},
+					Right: &huffman.Node{
+						Char:  'f',
+						Freq:  3,
+						Left:  nil,
+						Right: nil,
+					},
+				},
+			},
+		},
+		{
+			name: "tree with only root",
+			root: &huffman.Node{
+				Char:  'g',
+				Freq:  7,
+				Left:  nil,
+				Right: nil,
+			},
+		},
+		{
+			name: "tree with deep nesting",
+			root: &huffman.Node{
+				Char: 0,
+				Freq: 15,
+				Left: &huffman.Node{
+					Char:  'h',
+					Freq:  5,
+					Left:  nil,
+					Right: nil,
+				},
+				Right: &huffman.Node{
+					Char: 0,
+					Freq: 10,
+					Left: &huffman.Node{
+						Char:  'i',
+						Freq:  4,
+						Left:  nil,
+						Right: nil,
+					},
+					Right: &huffman.Node{
+						Char:  'j',
+						Freq:  6,
+						Left:  nil,
+						Right: nil,
+					},
+				},
+			},
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			serialized, err := huffman.SerializeTree(tc.root)
+			if err != nil {
+				t.Errorf("Deserialization failed")
+			}
+			root, err := huffman.DeserializeTree(serialized)
+			if err != nil {
+				t.Errorf("Deserialization failed")
+			}
+			if !checkIfEqual(tc.root, root) {
+				t.Errorf("Deserialization failed")
+			}
+		})
+	}
+
+}