test: add test for new read_host_from_playbook function

tdp/core/test_collection.py

@@ -11,8 +11,10 @@
     MissingMandatoryDirectoryError,
     PathDoesNotExistsError,
     PathIsNotADirectoryError,
+    read_host_from_playbook,
 )
 from tdp.core.constants import DAG_DIRECTORY_NAME
+from tdp.core.models.test_deployment_log import MockInventoryReader
 
 
 def test_collection_from_path_does_not_exist():
@@ -50,3 +52,25 @@ def test_collection_from_path(tmp_path_factory: pytest.TempPathFactory):
     assert collection_path / DAG_DIRECTORY_NAME / "service.yml" in collection.dag_yamls
     assert "service_install" in collection.playbooks
     assert "service_config" in collection.playbooks
+
+
+def test_read_host_from_playbook(tmp_path: Path):
+    # Create a temporary playbook file
+    playbook_path = tmp_path / "playbook.yml"
+    playbook_path.write_text(
+        """---
+        - name: Play 1
+          hosts: host1, host2
+          tasks:
+            - name: Task 1
+              command: echo "Hello, World!"
+        """
+    )
+
+    # Call the function under test
+    hosts = read_host_from_playbook(
+        playbook_path, MockInventoryReader(["host1", "host2"])
+    )
+
+    # Assert the expected result
+    assert hosts == {"host1", "host2"}