Relax type requirement from Sequence to Iterable for get_flattened phases

Add test case showing where this is useful

PiperOrigin-RevId: 761319671

Author: glados-verma

openhtf/util/test.py

@@ -1016,7 +1016,7 @@ def get_profile_filepath(cls) -> Optional[pathlib.Path]:
 
 
 def get_flattened_phases(
-    node_collections: Sequence[
+    node_collections: Iterable[
         Union[phase_nodes.PhaseNode, phase_collections.PhaseCollectionNode]
     ],
 ) -> Sequence[phase_nodes.PhaseNode]:

test/util/test_test.py

@@ -358,16 +358,17 @@ def test_profile_test(self):
             '.', os.path.sep), output)
 
 
-class GetFlattenedPhasesTest(unittest.TestCase):
+def no_op_phase():
+  """No-op phase."""
+
 
-  def test_unflattens_nested_mixed_nodes(self):
+def make_phase(name: str):
+  return openhtf.PhaseOptions(name=name)(no_op_phase)
 
-    def no_op_phase():
-      """No-op phase."""
 
-    def make_phase(name: str):
-      return openhtf.PhaseOptions(name=name)(no_op_phase)
+class GetFlattenedPhasesTest(unittest.TestCase):
 
+  def test_unflattens_nested_mixed_nodes_list(self):
     nested_nodes = [
         make_phase('TopLevelPhase'),
         [make_phase('NestedPhase1'), make_phase('NestedPhase2')],
@@ -410,3 +411,22 @@ def make_phase(name: str):
             'NestedPhase3',
         ],
     )
+
+  def test_unflattens_nested_mixed_nodes_iterable(self):
+    nodes_iterable = openhtf.PhaseGroup(
+        setup=make_phase('SetupPhase1a'),
+        main=[make_phase('MainPhase1a'), make_phase('MainPhase1b')],
+        teardown=make_phase('TeardownPhase1a'),
+    ).all_phases()
+    node_names = []
+    for node in test.get_flattened_phases(nodes_iterable):
+      node_names.append(node.name)
+    self.assertEqual(
+        node_names,
+        [
+            'SetupPhase1a',
+            'MainPhase1a',
+            'MainPhase1b',
+            'TeardownPhase1a',
+        ],
+    )