Consolidate test fixtures

Introduce shared fixture helpers for Test::Unit and RSpec to
reduce repeated tree setup logic. Wire both suites to the shared
helpers and add standard file headers.

Author: evolve75

spec/spec_helper.rb

@@ -10,6 +10,7 @@
 # frozen_string_literal: true
 
 require 'tree'
+require_relative 'support/fixtures'
 
 if ENV['COVERAGE']
   begin

spec/support/fixtures.rb

@@ -0,0 +1,36 @@
+# fixtures.rb - This file is part of the RubyTree package.
+#
+# Copyright (c) 2026 Anupam Sengupta. All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without modification,
+# are permitted provided that the following conditions are met:
+#
+# - Redistributions of source code must retain the above copyright notice, this
+#   list of conditions and the following disclaimer.
+#
+# - Redistributions in binary form must reproduce the above copyright notice, this
+#   list of conditions and the following disclaimer in the documentation and/or
+#   other materials provided with the distribution.
+#
+# - Neither the name of the organization nor the names of its contributors may
+#   be used to endorse or promote products derived from this software without
+#   specific prior written permission.
+#
+#   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+# ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+# (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+# LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+# ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+# SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+#
+# frozen_string_literal: true
+
+require_relative '../../test/support/fixtures_shared'
+
+RSpec.configure do |config|
+  config.include TreeTestFixtures
+end

test/support/fixtures_shared.rb

@@ -0,0 +1,73 @@
+# fixtures_shared.rb - This file is part of the RubyTree package.
+#
+# Copyright (c) 2026 Anupam Sengupta. All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without modification,
+# are permitted provided that the following conditions are met:
+#
+# - Redistributions of source code must retain the above copyright notice, this
+#   list of conditions and the following disclaimer.
+#
+# - Redistributions in binary form must reproduce the above copyright notice, this
+#   list of conditions and the following disclaimer in the documentation and/or
+#   other materials provided with the distribution.
+#
+# - Neither the name of the organization nor the names of its contributors may
+#   be used to endorse or promote products derived from this software without
+#   specific prior written permission.
+#
+#   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+# ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+# (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+# LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+# ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+# SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+#
+# frozen_string_literal: true
+
+module TreeTestFixtures
+  def build_basic_tree_nodes
+    root = Tree::TreeNode.new('ROOT', 'Root Node')
+    child1 = Tree::TreeNode.new('Child1', 'Child Node 1')
+    child2 = Tree::TreeNode.new('Child2', 'Child Node 2')
+    child3 = Tree::TreeNode.new('Child3', 'Child Node 3')
+    child4 = Tree::TreeNode.new('Child4', 'Grand Child 1')
+    child5 = Tree::TreeNode.new('Child5', 'Child Node 4')
+
+    {
+      root: root,
+      child1: child1,
+      child2: child2,
+      child3: child3,
+      child4: child4,
+      child5: child5
+    }
+  end
+
+  def attach_basic_tree(nodes)
+    nodes[:root] << nodes[:child1]
+    nodes[:root] << nodes[:child2]
+    nodes[:root] << nodes[:child3] << nodes[:child4]
+    nodes
+  end
+
+  def build_basic_tree
+    attach_basic_tree(build_basic_tree_nodes)
+  end
+
+  def build_binary_tree_nodes
+    root = Tree::BinaryTreeNode.new('ROOT', 'Root Node')
+    left_child1 = Tree::BinaryTreeNode.new('A Child at Left', 'Child Node @ left')
+    right_child1 = Tree::BinaryTreeNode.new('B Child at Right', 'Child Node @ right')
+
+    {
+      root: root,
+      left_child1: left_child1,
+      right_child1: right_child1
+    }
+  end
+end

test/test_binarytree.rb

@@ -36,16 +36,18 @@
 
 require 'test/unit'
 require_relative '../lib/tree/binarytree'
+require_relative 'support/fixtures_shared'
 
 module TestTree
   # Test class for the binary tree node.
   class TestBinaryTreeNode < Test::Unit::TestCase
+    include TreeTestFixtures
     # Setup the test data scaffolding.
     def setup
-      @root = Tree::BinaryTreeNode.new('ROOT', 'Root Node')
-
-      @left_child1  = Tree::BinaryTreeNode.new('A Child at Left', 'Child Node @ left')
-      @right_child1 = Tree::BinaryTreeNode.new('B Child at Right', 'Child Node @ right')
+      nodes = build_binary_tree_nodes
+      @root = nodes[:root]
+      @left_child1 = nodes[:left_child1]
+      @right_child1 = nodes[:right_child1]
     end
 
     # Tear down the test data scaffolding.

test/test_tree.rb

@@ -34,11 +34,13 @@
 require 'test/unit'
 require 'json'
 require_relative '../lib/tree/tree_deps'
+require_relative 'support/fixtures_shared'
 
 module TestTree
   # Test class for the Tree node.
   # noinspection RubyTooManyInstanceVariablesInspection
   class TestTreeNode < Test::Unit::TestCase
+    include TreeTestFixtures
     Person = Struct.new(:First, :last) # A simple structure to use as the content for the nodes.
 
     # Create this structure for the tests
@@ -61,20 +63,25 @@ class TestTreeNode < Test::Unit::TestCase
     #
     # Some basic setup to create the nodes for the test tree.
     def setup
-      @root = Tree::TreeNode.new('ROOT', 'Root Node')
-
-      @child1 = Tree::TreeNode.new('Child1', 'Child Node 1')
-      @child2 = Tree::TreeNode.new('Child2', 'Child Node 2')
-      @child3 = Tree::TreeNode.new('Child3', 'Child Node 3')
-      @child4 = Tree::TreeNode.new('Child4', 'Grand Child 1')
-      @child5 = Tree::TreeNode.new('Child5', 'Child Node 4')
+      nodes = build_basic_tree_nodes
+      @root = nodes[:root]
+      @child1 = nodes[:child1]
+      @child2 = nodes[:child2]
+      @child3 = nodes[:child3]
+      @child4 = nodes[:child4]
+      @child5 = nodes[:child5]
     end
 
     # Create the actual test tree.
     def setup_test_tree
-      @root << @child1
-      @root << @child2
-      @root << @child3 << @child4
+      attach_basic_tree(
+        root: @root,
+        child1: @child1,
+        child2: @child2,
+        child3: @child3,
+        child4: @child4,
+        child5: @child5
+      )
     end
 
     # Tear down the entire structure