diff --git a/test/models/unit/lifecycle_environment_test.rb b/test/models/unit/lifecycle_environment_test.rb
new file mode 100644
index 00000000..7b270851
--- /dev/null
+++ b/test/models/unit/lifecycle_environment_test.rb
@@ -0,0 +1,92 @@
+require 'foreman_ansible_director_test_helper'
+
+module ForemanAnsibleDirectorTests
+  module Models
+    module Unit
+      class LifecycleEnvironmentTest < ForemanAnsibleDirectorTestCase
+        setup do
+          @path = FactoryBot.create(:lifecycle_environment_path, organization: @organization)
+          @environment = FactoryBot.create(
+            :lifecycle_environment,
+            organization: @organization,
+            lifecycle_environment_path: @path
+          )
+          @collection = FactoryBot.create(:ansible_collection, organization: @organization)
+          @version = FactoryBot.create(:content_unit_version, versionable: @collection)
+        end
+
+        test 'content_unit_versions returns direct content without snapshot' do
+          @environment.assign_content_unit_version!(@version)
+
+          assert_equal [@version], @environment.content_unit_versions.to_a
+        end
+
+        test 'content_unit_versions returns snapshot content when snapshot is assigned' do
+          direct_version = FactoryBot.create(:content_unit_version, versionable: @collection)
+          snapshot = FactoryBot.create(:content_snapshot, references: 1)
+          FactoryBot.create(
+            :content_snapshot_content_unit_version,
+            content_snapshot: snapshot,
+            content_unit_version: @version
+          )
+          @environment.assign_content_unit_version!(direct_version)
+          @environment.update!(content_snapshot: snapshot)
+
+          assert_equal [@version], @environment.content_unit_versions.to_a
+        end
+
+        test 'content_hash returns snapshot content hash when snapshot is assigned' do
+          snapshot = FactoryBot.create(:content_snapshot, content_hash: 'snapshot')
+          @environment.assign_content_unit_version!(@version)
+          @environment.update!(content_snapshot: snapshot)
+
+          assert_equal 'snapshot', @environment.content_hash
+        end
+
+        test 'assign_execution_environment! assigns existing execution environment' do
+          execution_environment = FactoryBot.create(:execution_environment, organization: @organization)
+
+          assert @environment.assign_execution_environment!(execution_environment.id)
+          assert_equal execution_environment.id, @environment.reload.execution_environment_id
+        end
+
+        test 'assign_execution_environment! returns false for missing execution environment' do
+          assert_equal false, @environment.assign_execution_environment!(-1)
+          assert_includes @environment.errors[:execution_environment_id], 'not found'
+        end
+
+        test 'root and leaf reflect linked path position' do
+          child = FactoryBot.create(
+            :lifecycle_environment,
+            organization: @organization,
+            lifecycle_environment_path: @path,
+            parent: @environment
+          )
+          @environment.update!(child: child)
+
+          assert @environment.root?
+          assert_not @environment.leaf?
+          assert_not child.root?
+          assert child.leaf?
+        end
+
+        test 'ancestors returns parents recursively' do
+          child = FactoryBot.create(
+            :lifecycle_environment,
+            organization: @organization,
+            lifecycle_environment_path: @path,
+            parent: @environment
+          )
+          grandchild = FactoryBot.create(
+            :lifecycle_environment,
+            organization: @organization,
+            lifecycle_environment_path: @path,
+            parent: child
+          )
+
+          assert_equal [child, @environment], grandchild.ancestors
+        end
+      end
+    end
+  end
+end