tests/bindings/python/bt2/test_message_iterator.py

   1 # SPDX-License-Identifier: GPL-2.0-only
   2 #
   3 # Copyright (C) 2019 EfficiOS Inc.
   4 #
   5
   6 import unittest
   7 import bt2
   8 import sys
   9 from utils import TestOutputPortMessageIterator
  10 from bt2 import port as bt2_port
  11 from bt2 import message_iterator as bt2_message_iterator
  12
  13
  14 class SimpleSink(bt2._UserSinkComponent):
  15     # Straightforward sink that creates one input port (`in`) and consumes from
  16     # it.
  17
  18     def __init__(self, config, params, obj):
  19         self._add_input_port("in")
  20
  21     def _user_consume(self):
  22         next(self._msg_iter)
  23
  24     def _user_graph_is_configured(self):
  25         self._msg_iter = self._create_message_iterator(self._input_ports["in"])
  26
  27
  28 def _create_graph(src_comp_cls, sink_comp_cls, flt_comp_cls=None):
  29     graph = bt2.Graph()
  30
  31     src_comp = graph.add_component(src_comp_cls, "src")
  32     sink_comp = graph.add_component(sink_comp_cls, "sink")
  33
  34     if flt_comp_cls is not None:
  35         flt_comp = graph.add_component(flt_comp_cls, "flt")
  36         graph.connect_ports(src_comp.output_ports["out"], flt_comp.input_ports["in"])
  37         graph.connect_ports(flt_comp.output_ports["out"], sink_comp.input_ports["in"])
  38     else:
  39         graph.connect_ports(src_comp.output_ports["out"], sink_comp.input_ports["in"])
  40
  41     return graph
  42
  43
  44 class UserMessageIteratorTestCase(unittest.TestCase):
  45     def test_init(self):
  46         the_output_port_from_source = None
  47         the_output_port_from_iter = None
  48
  49         class MyIter(bt2._UserMessageIterator):
  50             def __init__(self, config, self_port_output):
  51                 nonlocal initialized
  52                 nonlocal the_output_port_from_iter
  53                 initialized = True
  54                 the_output_port_from_iter = self_port_output
  55
  56         class MySource(bt2._UserSourceComponent, message_iterator_class=MyIter):
  57             def __init__(self, config, params, obj):
  58                 nonlocal the_output_port_from_source
  59                 the_output_port_from_source = self._add_output_port("out", "user data")
  60
  61         initialized = False
  62         graph = _create_graph(MySource, SimpleSink)
  63         graph.run()
  64         self.assertTrue(initialized)
  65         self.assertEqual(
  66             the_output_port_from_source.addr, the_output_port_from_iter.addr
  67         )
  68         self.assertEqual(the_output_port_from_iter.user_data, "user data")
  69
  70     def test_create_from_message_iterator(self):
  71         class MySourceIter(bt2._UserMessageIterator):
  72             def __init__(self, config, self_port_output):
  73                 nonlocal src_iter_initialized
  74                 src_iter_initialized = True
  75
  76         class MySource(bt2._UserSourceComponent, message_iterator_class=MySourceIter):
  77             def __init__(self, config, params, obj):
  78                 self._add_output_port("out")
  79
  80         class MyFilterIter(bt2._UserMessageIterator):
  81             def __init__(self, config, self_port_output):
  82                 nonlocal flt_iter_initialized
  83                 flt_iter_initialized = True
  84                 self._up_iter = self._create_message_iterator(
  85                     self._component._input_ports["in"]
  86                 )
  87
  88             def __next__(self):
  89                 return next(self._up_iter)
  90
  91         class MyFilter(bt2._UserFilterComponent, message_iterator_class=MyFilterIter):
  92             def __init__(self, config, params, obj):
  93                 self._add_input_port("in")
  94                 self._add_output_port("out")
  95
  96         src_iter_initialized = False
  97         flt_iter_initialized = False
  98         graph = _create_graph(MySource, SimpleSink, MyFilter)
  99         graph.run()
 100         self.assertTrue(src_iter_initialized)
 101         self.assertTrue(flt_iter_initialized)
 102
 103     # Test that creating a message iterator from a sink component on a
 104     # non-connected inport port raises.
 105     def test_create_from_sink_component_unconnected_port_raises(self):
 106         class MySink(bt2._UserSinkComponent):
 107             def __init__(comp_self, config, params, obj):
 108                 comp_self._input_port = comp_self._add_input_port("in")
 109
 110             def _user_graph_is_configured(comp_self):
 111                 with self.assertRaisesRegex(ValueError, "input port is not connected"):
 112                     comp_self._create_message_iterator(comp_self._input_port)
 113
 114                 nonlocal seen
 115                 seen = True
 116
 117             def _user_consume(self):
 118                 raise bt2.Stop
 119
 120         seen = False
 121         graph = bt2.Graph()
 122         graph.add_component(MySink, "snk")
 123         graph.run()
 124         self.assertTrue(seen)
 125
 126     # Test that creating a message iterator from a message iteartor on a
 127     # non-connected inport port raises.
 128     def test_create_from_message_iterator_unconnected_port_raises(self):
 129         class MyFilterIter(bt2._UserMessageIterator):
 130             def __init__(iter_self, config, port):
 131                 input_port = iter_self._component._input_ports["in"]
 132
 133                 with self.assertRaisesRegex(ValueError, "input port is not connected"):
 134                     iter_self._create_message_iterator(input_port)
 135
 136                 nonlocal seen
 137                 seen = True
 138
 139         class MyFilter(bt2._UserFilterComponent, message_iterator_class=MyFilterIter):
 140             def __init__(comp_self, config, params, obj):
 141                 comp_self._add_input_port("in")
 142                 comp_self._add_output_port("out")
 143
 144         class MySink(bt2._UserSinkComponent):
 145             def __init__(comp_self, config, params, obj):
 146                 comp_self._input_port = comp_self._add_input_port("in")
 147
 148             def _user_graph_is_configured(comp_self):
 149                 comp_self._input_iter = comp_self._create_message_iterator(
 150                     comp_self._input_port
 151                 )
 152
 153             def _user_consume(self):
 154                 raise bt2.Stop
 155
 156         seen = False
 157         graph = bt2.Graph()
 158         flt = graph.add_component(MyFilter, "flt")
 159         snk = graph.add_component(MySink, "snk")
 160         graph.connect_ports(flt.output_ports["out"], snk.input_ports["in"])
 161         graph.run()
 162         self.assertTrue(seen)
 163
 164     def test_create_user_error(self):
 165         # This tests both error handling by
 166         # _UserSinkComponent._create_message_iterator
 167         # and _UserMessageIterator._create_message_iterator, as they
 168         # are both used in the graph.
 169         class MySourceIter(bt2._UserMessageIterator):
 170             def __init__(self, config, self_port_output):
 171                 raise ValueError("Very bad error")
 172
 173         class MySource(bt2._UserSourceComponent, message_iterator_class=MySourceIter):
 174             def __init__(self, config, params, obj):
 175                 self._add_output_port("out")
 176
 177         class MyFilterIter(bt2._UserMessageIterator):
 178             def __init__(self, config, self_port_output):
 179                 # This is expected to raise because of the error in
 180                 # MySourceIter.__init__.
 181                 self._create_message_iterator(self._component._input_ports["in"])
 182
 183         class MyFilter(bt2._UserFilterComponent, message_iterator_class=MyFilterIter):
 184             def __init__(self, config, params, obj):
 185                 self._add_input_port("in")
 186                 self._add_output_port("out")
 187
 188         graph = _create_graph(MySource, SimpleSink, MyFilter)
 189
 190         with self.assertRaises(bt2._Error) as ctx:
 191             graph.run()
 192
 193         exc = ctx.exception
 194         cause = exc[0]
 195
 196         self.assertIsInstance(cause, bt2._MessageIteratorErrorCause)
 197         self.assertEqual(cause.component_name, "src")
 198         self.assertEqual(cause.component_output_port_name, "out")
 199         self.assertIn("ValueError: Very bad error", cause.message)
 200
 201     def test_finalize(self):
 202         class MyIter(bt2._UserMessageIterator):
 203             def _user_finalize(self):
 204                 nonlocal finalized
 205                 finalized = True
 206
 207         class MySource(bt2._UserSourceComponent, message_iterator_class=MyIter):
 208             def __init__(self, config, params, obj):
 209                 self._add_output_port("out")
 210
 211         finalized = False
 212         graph = _create_graph(MySource, SimpleSink)
 213         graph.run()
 214         del graph
 215         self.assertTrue(finalized)
 216
 217     def test_config_parameter(self):
 218         class MyIter(bt2._UserMessageIterator):
 219             def __init__(self, config, port):
 220                 nonlocal config_type
 221                 config_type = type(config)
 222
 223         class MySource(bt2._UserSourceComponent, message_iterator_class=MyIter):
 224             def __init__(self, config, params, obj):
 225                 self._add_output_port("out")
 226
 227         config_type = None
 228         graph = _create_graph(MySource, SimpleSink)
 229         graph.run()
 230         self.assertIs(config_type, bt2_message_iterator._MessageIteratorConfiguration)
 231
 232     def _test_config_can_seek_forward(self, set_can_seek_forward):
 233         class MyIter(bt2._UserMessageIterator):
 234             def __init__(self, config, port):
 235                 if set_can_seek_forward:
 236                     config.can_seek_forward = True
 237
 238         class MySource(bt2._UserSourceComponent, message_iterator_class=MyIter):
 239             def __init__(self, config, params, obj):
 240                 self._add_output_port("out")
 241
 242         class MySink(bt2._UserSinkComponent):
 243             def __init__(self, config, params, obj):
 244                 self._add_input_port("in")
 245
 246             def _user_graph_is_configured(self):
 247                 self._msg_iter = self._create_message_iterator(self._input_ports["in"])
 248
 249             def _user_consume(self):
 250                 nonlocal can_seek_forward
 251                 can_seek_forward = self._msg_iter.can_seek_forward
 252
 253         can_seek_forward = None
 254         graph = _create_graph(MySource, MySink)
 255         graph.run_once()
 256         self.assertIs(can_seek_forward, set_can_seek_forward)
 257
 258     def test_config_can_seek_forward_default(self):
 259         self._test_config_can_seek_forward(False)
 260
 261     def test_config_can_seek_forward(self):
 262         self._test_config_can_seek_forward(True)
 263
 264     def test_config_can_seek_forward_wrong_type(self):
 265         class MyIter(bt2._UserMessageIterator):
 266             def __init__(self, config, port):
 267                 config.can_seek_forward = 1
 268
 269         class MySource(bt2._UserSourceComponent, message_iterator_class=MyIter):
 270             def __init__(self, config, params, obj):
 271                 self._add_output_port("out")
 272
 273         graph = _create_graph(MySource, SimpleSink)
 274         with self.assertRaises(bt2._Error) as ctx:
 275             graph.run()
 276
 277         root_cause = ctx.exception[0]
 278         self.assertIn("TypeError: 'int' is not a 'bool' object", root_cause.message)
 279
 280     def test_component(self):
 281         class MyIter(bt2._UserMessageIterator):
 282             def __init__(self, config, self_port_output):
 283                 nonlocal salut
 284                 salut = self._component._salut
 285
 286         class MySource(bt2._UserSourceComponent, message_iterator_class=MyIter):
 287             def __init__(self, config, params, obj):
 288                 self._add_output_port("out")
 289                 self._salut = 23
 290
 291         salut = None
 292         graph = _create_graph(MySource, SimpleSink)
 293         graph.run()
 294         self.assertEqual(salut, 23)
 295
 296     def test_port(self):
 297         class MyIter(bt2._UserMessageIterator):
 298             def __init__(self_iter, config, self_port_output):
 299                 nonlocal called
 300                 called = True
 301                 port = self_iter._port
 302                 self.assertIs(type(self_port_output), bt2_port._UserComponentOutputPort)
 303                 self.assertIs(type(port), bt2_port._UserComponentOutputPort)
 304                 self.assertEqual(self_port_output.addr, port.addr)
 305
 306         class MySource(bt2._UserSourceComponent, message_iterator_class=MyIter):
 307             def __init__(self, config, params, obj):
 308                 self._add_output_port("out")
 309
 310         called = False
 311         graph = _create_graph(MySource, SimpleSink)
 312         graph.run()
 313         self.assertTrue(called)
 314
 315     def test_addr(self):
 316         class MyIter(bt2._UserMessageIterator):
 317             def __init__(self, config, self_port_output):
 318                 nonlocal addr
 319                 addr = self.addr
 320
 321         class MySource(bt2._UserSourceComponent, message_iterator_class=MyIter):
 322             def __init__(self, config, params, obj):
 323                 self._add_output_port("out")
 324
 325         addr = None
 326         graph = _create_graph(MySource, SimpleSink)
 327         graph.run()
 328         self.assertIsNotNone(addr)
 329         self.assertNotEqual(addr, 0)
 330
 331     # Test that messages returned by _UserMessageIterator.__next__ remain valid
 332     # and can be re-used.
 333     def test_reuse_message(self):
 334         class MyIter(bt2._UserMessageIterator):
 335             def __init__(self, config, port):
 336                 tc, sc, ec = port.user_data
 337                 trace = tc()
 338                 stream = trace.create_stream(sc)
 339                 packet = stream.create_packet()
 340
 341                 # This message will be returned twice by __next__.
 342                 event_message = self._create_event_message(ec, packet)
 343
 344                 self._msgs = [
 345                     self._create_stream_beginning_message(stream),
 346                     self._create_packet_beginning_message(packet),
 347                     event_message,
 348                     event_message,
 349                 ]
 350
 351             def __next__(self):
 352                 return self._msgs.pop(0)
 353
 354         class MySource(bt2._UserSourceComponent, message_iterator_class=MyIter):
 355             def __init__(self, config, params, obj):
 356                 tc = self._create_trace_class()
 357                 sc = tc.create_stream_class(supports_packets=True)
 358                 ec = sc.create_event_class()
 359                 self._add_output_port("out", (tc, sc, ec))
 360
 361         graph = bt2.Graph()
 362         src = graph.add_component(MySource, "src")
 363         it = TestOutputPortMessageIterator(graph, src.output_ports["out"])
 364
 365         # Skip beginning messages.
 366         msg = next(it)
 367         self.assertIs(type(msg), bt2._StreamBeginningMessageConst)
 368         msg = next(it)
 369         self.assertIs(type(msg), bt2._PacketBeginningMessageConst)
 370
 371         msg_ev1 = next(it)
 372         msg_ev2 = next(it)
 373
 374         self.assertIs(type(msg_ev1), bt2._EventMessageConst)
 375         self.assertIs(type(msg_ev2), bt2._EventMessageConst)
 376         self.assertEqual(msg_ev1.addr, msg_ev2.addr)
 377
 378     # Try consuming many times from an iterator that always returns TryAgain.
 379     # This verifies that we are not missing an incref of Py_None, making the
 380     # refcount of Py_None reach 0.
 381     def test_try_again_many_times(self):
 382         class MyIter(bt2._UserMessageIterator):
 383             def __next__(self):
 384                 raise bt2.TryAgain
 385
 386         class MySource(bt2._UserSourceComponent, message_iterator_class=MyIter):
 387             def __init__(self, config, params, obj):
 388                 self._add_output_port("out")
 389
 390         class MyFilterIter(bt2._UserMessageIterator):
 391             def __init__(self, port):
 392                 input_port = port.user_data
 393                 self._upstream_iter = self._create_message_iterator(input_port)
 394
 395             def __next__(self):
 396                 return next(self._upstream_iter)
 397
 398             def _user_seek_beginning(self):
 399                 self._upstream_iter.seek_beginning()
 400
 401             def _user_can_seek_beginning(self):
 402                 return self._upstream_iter.can_seek_beginning()
 403
 404         class MyFilter(bt2._UserFilterComponent, message_iterator_class=MyFilterIter):
 405             def __init__(self, config, params, obj):
 406                 input_port = self._add_input_port("in")
 407                 self._add_output_port("out", input_port)
 408
 409         graph = bt2.Graph()
 410         src = graph.add_component(MySource, "src")
 411         it = TestOutputPortMessageIterator(graph, src.output_ports["out"])
 412
 413         # Three times the initial ref count of `None` iterations should
 414         # be enough to catch the bug even if there are small differences
 415         # between configurations.
 416         none_ref_count = sys.getrefcount(None) * 3
 417
 418         for i in range(none_ref_count):
 419             with self.assertRaises(bt2.TryAgain):
 420                 next(it)
 421
 422     def test_error_in_iterator_with_cycle_after_having_created_upstream_iterator(self):
 423         # Test a failure that triggered an abort in libbabeltrace2, in this situation:
 424         #
 425         #   - The filter iterator creates an upstream iterator.
 426         #   - The filter iterator creates a reference cycle, including itself.
 427         #   - An exception is raised, causing the filter iterator's
 428         #     initialization method to fail.
 429         class MySourceIter(bt2._UserMessageIterator):
 430             pass
 431
 432         class MySource(bt2._UserSourceComponent, message_iterator_class=MySourceIter):
 433             def __init__(self, config, params, obj):
 434                 self._add_output_port("out")
 435
 436         class MyFilterIter(bt2._UserMessageIterator):
 437             def __init__(self, config, port):
 438                 # First, create an upstream iterator.
 439                 self._upstream_iter = self._create_message_iterator(
 440                     self._component._input_ports["in"]
 441                 )
 442
 443                 # Then, voluntarily make a reference cycle that will keep this
 444                 # Python object alive, which will keep the upstream iterator
 445                 # Babeltrace object alive.
 446                 self._self = self
 447
 448                 # Finally, raise an exception to make __init__ fail.
 449                 raise ValueError("woops")
 450
 451         class MyFilter(bt2._UserFilterComponent, message_iterator_class=MyFilterIter):
 452             def __init__(self, config, params, obj):
 453                 self._in = self._add_input_port("in")
 454                 self._out = self._add_output_port("out")
 455
 456         class MySink(bt2._UserSinkComponent):
 457             def __init__(self, config, params, obj):
 458                 self._input_port = self._add_input_port("in")
 459
 460             def _user_graph_is_configured(self):
 461                 self._upstream_iter = self._create_message_iterator(self._input_port)
 462
 463             def _user_consume(self):
 464                 # We should not reach this.
 465                 assert False
 466
 467         g = bt2.Graph()
 468         src = g.add_component(MySource, "src")
 469         flt = g.add_component(MyFilter, "flt")
 470         snk = g.add_component(MySink, "snk")
 471         g.connect_ports(src.output_ports["out"], flt.input_ports["in"])
 472         g.connect_ports(flt.output_ports["out"], snk.input_ports["in"])
 473
 474         with self.assertRaisesRegex(bt2._Error, "ValueError: woops"):
 475             g.run()
 476
 477
 478 def _setup_seek_test(
 479     sink_cls,
 480     user_seek_beginning=None,
 481     user_can_seek_beginning=None,
 482     user_seek_ns_from_origin=None,
 483     user_can_seek_ns_from_origin=None,
 484     can_seek_forward=False,
 485 ):
 486     class MySourceIter(bt2._UserMessageIterator):
 487         def __init__(self, config, port):
 488             tc, sc, ec = port.user_data
 489             trace = tc()
 490             stream = trace.create_stream(sc)
 491             packet = stream.create_packet()
 492
 493             self._msgs = [
 494                 self._create_stream_beginning_message(stream),
 495                 self._create_packet_beginning_message(packet),
 496                 self._create_event_message(ec, packet),
 497                 self._create_event_message(ec, packet),
 498                 self._create_packet_end_message(packet),
 499                 self._create_stream_end_message(stream),
 500             ]
 501             self._at = 0
 502             config.can_seek_forward = can_seek_forward
 503
 504         def __next__(self):
 505             if self._at < len(self._msgs):
 506                 msg = self._msgs[self._at]
 507                 self._at += 1
 508                 return msg
 509             else:
 510                 raise StopIteration
 511
 512     if user_seek_beginning is not None:
 513         MySourceIter._user_seek_beginning = user_seek_beginning
 514
 515     if user_can_seek_beginning is not None:
 516         MySourceIter._user_can_seek_beginning = user_can_seek_beginning
 517
 518     if user_seek_ns_from_origin is not None:
 519         MySourceIter._user_seek_ns_from_origin = user_seek_ns_from_origin
 520
 521     if user_can_seek_ns_from_origin is not None:
 522         MySourceIter._user_can_seek_ns_from_origin = user_can_seek_ns_from_origin
 523
 524     class MySource(bt2._UserSourceComponent, message_iterator_class=MySourceIter):
 525         def __init__(self, config, params, obj):
 526             tc = self._create_trace_class()
 527             sc = tc.create_stream_class(supports_packets=True)
 528             ec = sc.create_event_class()
 529
 530             self._add_output_port("out", (tc, sc, ec))
 531
 532     class MyFilterIter(bt2._UserMessageIterator):
 533         def __init__(self, config, port):
 534             self._upstream_iter = self._create_message_iterator(
 535                 self._component._input_ports["in"]
 536             )
 537             config.can_seek_forward = self._upstream_iter.can_seek_forward
 538
 539         def __next__(self):
 540             return next(self._upstream_iter)
 541
 542         def _user_can_seek_beginning(self):
 543             return self._upstream_iter.can_seek_beginning()
 544
 545         def _user_seek_beginning(self):
 546             self._upstream_iter.seek_beginning()
 547
 548         def _user_can_seek_ns_from_origin(self, ns_from_origin):
 549             return self._upstream_iter.can_seek_ns_from_origin(ns_from_origin)
 550
 551         def _user_seek_ns_from_origin(self, ns_from_origin):
 552             self._upstream_iter.seek_ns_from_origin(ns_from_origin)
 553
 554     class MyFilter(bt2._UserFilterComponent, message_iterator_class=MyFilterIter):
 555         def __init__(self, config, params, obj):
 556             self._add_input_port("in")
 557             self._add_output_port("out")
 558
 559     return _create_graph(MySource, sink_cls, flt_comp_cls=MyFilter)
 560
 561
 562 class UserMessageIteratorSeekBeginningTestCase(unittest.TestCase):
 563     def test_can_seek_beginning_without_seek_beginning(self):
 564         with self.assertRaisesRegex(
 565             bt2._IncompleteUserClass,
 566             "cannot create component class 'MySource': message iterator class implements _user_can_seek_beginning but not _user_seek_beginning",
 567         ):
 568             _setup_seek_test(SimpleSink, user_can_seek_beginning=lambda: None)
 569
 570     def test_can_seek_beginning(self):
 571         class MySink(bt2._UserSinkComponent):
 572             def __init__(self, config, params, obj):
 573                 self._add_input_port("in")
 574
 575             def _user_graph_is_configured(self):
 576                 self._msg_iter = self._create_message_iterator(self._input_ports["in"])
 577
 578             def _user_consume(self):
 579                 nonlocal can_seek_beginning
 580                 can_seek_beginning = self._msg_iter.can_seek_beginning()
 581
 582         def _user_can_seek_beginning(self):
 583             nonlocal input_port_iter_can_seek_beginning
 584             return input_port_iter_can_seek_beginning
 585
 586         graph = _setup_seek_test(
 587             MySink,
 588             user_can_seek_beginning=_user_can_seek_beginning,
 589             user_seek_beginning=lambda: None,
 590         )
 591
 592         input_port_iter_can_seek_beginning = True
 593         can_seek_beginning = None
 594         graph.run_once()
 595         self.assertIs(can_seek_beginning, True)
 596
 597         input_port_iter_can_seek_beginning = False
 598         can_seek_beginning = None
 599         graph.run_once()
 600         self.assertIs(can_seek_beginning, False)
 601
 602     def test_no_can_seek_beginning_with_seek_beginning(self):
 603         # Test an iterator without a _user_can_seek_beginning method, but with
 604         # a _user_seek_beginning method.
 605         class MySink(bt2._UserSinkComponent):
 606             def __init__(self, config, params, obj):
 607                 self._add_input_port("in")
 608
 609             def _user_graph_is_configured(self):
 610                 self._msg_iter = self._create_message_iterator(self._input_ports["in"])
 611
 612             def _user_consume(self):
 613                 nonlocal can_seek_beginning
 614                 can_seek_beginning = self._msg_iter.can_seek_beginning()
 615
 616         def _user_seek_beginning(self):
 617             pass
 618
 619         graph = _setup_seek_test(MySink, user_seek_beginning=_user_seek_beginning)
 620         can_seek_beginning = None
 621         graph.run_once()
 622         self.assertIs(can_seek_beginning, True)
 623
 624     def test_no_can_seek_beginning(self):
 625         # Test an iterator without a _user_can_seek_beginning method, without
 626         # a _user_seek_beginning method.
 627         class MySink(bt2._UserSinkComponent):
 628             def __init__(self, config, params, obj):
 629                 self._add_input_port("in")
 630
 631             def _user_graph_is_configured(self):
 632                 self._msg_iter = self._create_message_iterator(self._input_ports["in"])
 633
 634             def _user_consume(self):
 635                 nonlocal can_seek_beginning
 636                 can_seek_beginning = self._msg_iter.can_seek_beginning()
 637
 638         graph = _setup_seek_test(MySink)
 639         can_seek_beginning = None
 640         graph.run_once()
 641         self.assertIs(can_seek_beginning, False)
 642
 643     def test_can_seek_beginning_user_error(self):
 644         class MySink(bt2._UserSinkComponent):
 645             def __init__(self, config, params, obj):
 646                 self._add_input_port("in")
 647
 648             def _user_graph_is_configured(self):
 649                 self._msg_iter = self._create_message_iterator(self._input_ports["in"])
 650
 651             def _user_consume(self):
 652                 # This is expected to raise.
 653                 self._msg_iter.can_seek_beginning()
 654
 655         def _user_can_seek_beginning(self):
 656             raise ValueError("moustiquaire")
 657
 658         graph = _setup_seek_test(
 659             MySink,
 660             user_can_seek_beginning=_user_can_seek_beginning,
 661             user_seek_beginning=lambda: None,
 662         )
 663
 664         with self.assertRaises(bt2._Error) as ctx:
 665             graph.run_once()
 666
 667         cause = ctx.exception[0]
 668         self.assertIn("ValueError: moustiquaire", cause.message)
 669
 670     def test_can_seek_beginning_wrong_return_value(self):
 671         class MySink(bt2._UserSinkComponent):
 672             def __init__(self, config, params, obj):
 673                 self._add_input_port("in")
 674
 675             def _user_graph_is_configured(self):
 676                 self._msg_iter = self._create_message_iterator(self._input_ports["in"])
 677
 678             def _user_consume(self):
 679                 # This is expected to raise.
 680                 self._msg_iter.can_seek_beginning()
 681
 682         def _user_can_seek_beginning(self):
 683             return "Amqui"
 684
 685         graph = _setup_seek_test(
 686             MySink,
 687             user_can_seek_beginning=_user_can_seek_beginning,
 688             user_seek_beginning=lambda: None,
 689         )
 690
 691         with self.assertRaises(bt2._Error) as ctx:
 692             graph.run_once()
 693
 694         cause = ctx.exception[0]
 695         self.assertIn("TypeError: 'str' is not a 'bool' object", cause.message)
 696
 697     def test_seek_beginning(self):
 698         class MySink(bt2._UserSinkComponent):
 699             def __init__(self, config, params, obj):
 700                 self._add_input_port("in")
 701
 702             def _user_graph_is_configured(self):
 703                 self._msg_iter = self._create_message_iterator(self._input_ports["in"])
 704
 705             def _user_consume(self):
 706                 nonlocal do_seek_beginning
 707                 nonlocal msg
 708
 709                 if do_seek_beginning:
 710                     self._msg_iter.seek_beginning()
 711                     return
 712
 713                 msg = next(self._msg_iter)
 714
 715         def _user_seek_beginning(self):
 716             self._at = 0
 717
 718         msg = None
 719         graph = _setup_seek_test(MySink, user_seek_beginning=_user_seek_beginning)
 720
 721         # Consume message.
 722         do_seek_beginning = False
 723         graph.run_once()
 724         self.assertIs(type(msg), bt2._StreamBeginningMessageConst)
 725
 726         # Consume message.
 727         graph.run_once()
 728         self.assertIs(type(msg), bt2._PacketBeginningMessageConst)
 729
 730         # Seek beginning.
 731         do_seek_beginning = True
 732         graph.run_once()
 733
 734         # Consume message.
 735         do_seek_beginning = False
 736         graph.run_once()
 737         self.assertIs(type(msg), bt2._StreamBeginningMessageConst)
 738
 739     def test_seek_beginning_user_error(self):
 740         class MySink(bt2._UserSinkComponent):
 741             def __init__(self, config, params, obj):
 742                 self._add_input_port("in")
 743
 744             def _user_graph_is_configured(self):
 745                 self._msg_iter = self._create_message_iterator(self._input_ports["in"])
 746
 747             def _user_consume(self):
 748                 self._msg_iter.seek_beginning()
 749
 750         def _user_seek_beginning(self):
 751             raise ValueError("ouch")
 752
 753         graph = _setup_seek_test(MySink, user_seek_beginning=_user_seek_beginning)
 754
 755         with self.assertRaises(bt2._Error):
 756             graph.run_once()
 757
 758
 759 class UserMessageIteratorSeekNsFromOriginTestCase(unittest.TestCase):
 760     def test_can_seek_ns_from_origin_without_seek_ns_from_origin(self):
 761         # Test the case where:
 762         #
 763         #   - can_seek_ns_from_origin: Returns True (don't really care, as long
 764         #     as it's provided)
 765         #   - seek_ns_from_origin provided: No
 766         #   - can the iterator seek beginning: Don't care
 767         #   - can the iterator seek forward: Don't care
 768         for can_seek_ns_from_origin in (False, True):
 769             for iter_can_seek_beginning in (False, True):
 770                 for iter_can_seek_forward in (False, True):
 771                     with self.assertRaisesRegex(
 772                         bt2._IncompleteUserClass,
 773                         "cannot create component class 'MySource': message iterator class implements _user_can_seek_ns_from_origin but not _user_seek_ns_from_origin",
 774                     ):
 775                         self._can_seek_ns_from_origin_test(
 776                             None,
 777                             user_can_seek_ns_from_origin_ret_val=True,
 778                             user_seek_ns_from_origin_provided=False,
 779                             iter_can_seek_beginning=iter_can_seek_beginning,
 780                             iter_can_seek_forward=iter_can_seek_forward,
 781                         )
 782
 783     def test_can_seek_ns_from_origin_returns_true(self):
 784         # Test the case where:
 785         #
 786         #   - can_seek_ns_from_origin: returns True
 787         #   - seek_ns_from_origin provided: Yes
 788         #   - can the iterator seek beginning: Don't care
 789         #   - can the iterator seek forward: Don't care
 790         #
 791         # We expect iter.can_seek_ns_from_origin to return True.
 792         for iter_can_seek_beginning in (False, True):
 793             for iter_can_seek_forward in (False, True):
 794                 self._can_seek_ns_from_origin_test(
 795                     expected_outcome=True,
 796                     user_can_seek_ns_from_origin_ret_val=True,
 797                     user_seek_ns_from_origin_provided=True,
 798                     iter_can_seek_beginning=iter_can_seek_beginning,
 799                     iter_can_seek_forward=iter_can_seek_forward,
 800                 )
 801
 802     def test_can_seek_ns_from_origin_returns_false_can_seek_beginning_forward_seekable(
 803         self,
 804     ):
 805         # Test the case where:
 806         #
 807         #   - can_seek_ns_from_origin: returns False
 808         #   - seek_ns_from_origin provided: Yes
 809         #   - can the iterator seek beginning: Yes
 810         #   - can the iterator seek forward: Yes
 811         #
 812         # We expect iter.can_seek_ns_from_origin to return True.
 813         self._can_seek_ns_from_origin_test(
 814             expected_outcome=True,
 815             user_can_seek_ns_from_origin_ret_val=False,
 816             user_seek_ns_from_origin_provided=True,
 817             iter_can_seek_beginning=True,
 818             iter_can_seek_forward=True,
 819         )
 820
 821     def test_can_seek_ns_from_origin_returns_false_can_seek_beginning_not_forward_seekable(
 822         self,
 823     ):
 824         # Test the case where:
 825         #
 826         #   - can_seek_ns_from_origin: returns False
 827         #   - seek_ns_from_origin provided: Yes
 828         #   - can the iterator seek beginning: Yes
 829         #   - can the iterator seek forward: No
 830         #
 831         # We expect iter.can_seek_ns_from_origin to return False.
 832         self._can_seek_ns_from_origin_test(
 833             expected_outcome=False,
 834             user_can_seek_ns_from_origin_ret_val=False,
 835             user_seek_ns_from_origin_provided=True,
 836             iter_can_seek_beginning=True,
 837             iter_can_seek_forward=False,
 838         )
 839
 840     def test_can_seek_ns_from_origin_returns_false_cant_seek_beginning_forward_seekable(
 841         self,
 842     ):
 843         # Test the case where:
 844         #
 845         #   - can_seek_ns_from_origin: returns False
 846         #   - seek_ns_from_origin provided: Yes
 847         #   - can the iterator seek beginning: No
 848         #   - can the iterator seek forward: Yes
 849         #
 850         # We expect iter.can_seek_ns_from_origin to return False.
 851         self._can_seek_ns_from_origin_test(
 852             expected_outcome=False,
 853             user_can_seek_ns_from_origin_ret_val=False,
 854             user_seek_ns_from_origin_provided=True,
 855             iter_can_seek_beginning=False,
 856             iter_can_seek_forward=True,
 857         )
 858
 859     def test_can_seek_ns_from_origin_returns_false_cant_seek_beginning_not_forward_seekable(
 860         self,
 861     ):
 862         # Test the case where:
 863         #
 864         #   - can_seek_ns_from_origin: returns False
 865         #   - seek_ns_from_origin provided: Yes
 866         #   - can the iterator seek beginning: No
 867         #   - can the iterator seek forward: No
 868         #
 869         # We expect iter.can_seek_ns_from_origin to return False.
 870         self._can_seek_ns_from_origin_test(
 871             expected_outcome=False,
 872             user_can_seek_ns_from_origin_ret_val=False,
 873             user_seek_ns_from_origin_provided=True,
 874             iter_can_seek_beginning=False,
 875             iter_can_seek_forward=False,
 876         )
 877
 878     def test_no_can_seek_ns_from_origin_seek_ns_from_origin(self):
 879         # Test the case where:
 880         #
 881         #   - can_seek_ns_from_origin: Not provided
 882         #   - seek_ns_from_origin provided: Yes
 883         #   - can the iterator seek beginning: Don't care
 884         #   - can the iterator seek forward: Don't care
 885         #
 886         # We expect iter.can_seek_ns_from_origin to return True.
 887         for iter_can_seek_beginning in (False, True):
 888             for iter_can_seek_forward in (False, True):
 889                 self._can_seek_ns_from_origin_test(
 890                     expected_outcome=True,
 891                     user_can_seek_ns_from_origin_ret_val=None,
 892                     user_seek_ns_from_origin_provided=True,
 893                     iter_can_seek_beginning=iter_can_seek_beginning,
 894                     iter_can_seek_forward=iter_can_seek_forward,
 895                 )
 896
 897     def test_no_can_seek_ns_from_origin_no_seek_ns_from_origin_can_seek_beginning_forward_seekable(
 898         self,
 899     ):
 900         # Test the case where:
 901         #
 902         #   - can_seek_ns_from_origin: Not provided
 903         #   - seek_ns_from_origin provided: Not provided
 904         #   - can the iterator seek beginning: Yes
 905         #   - can the iterator seek forward: Yes
 906         #
 907         # We expect iter.can_seek_ns_from_origin to return True.
 908         self._can_seek_ns_from_origin_test(
 909             expected_outcome=True,
 910             user_can_seek_ns_from_origin_ret_val=None,
 911             user_seek_ns_from_origin_provided=False,
 912             iter_can_seek_beginning=True,
 913             iter_can_seek_forward=True,
 914         )
 915
 916     def test_no_can_seek_ns_from_origin_no_seek_ns_from_origin_can_seek_beginning_not_forward_seekable(
 917         self,
 918     ):
 919         # Test the case where:
 920         #
 921         #   - can_seek_ns_from_origin: Not provided
 922         #   - seek_ns_from_origin provided: Not provided
 923         #   - can the iterator seek beginning: Yes
 924         #   - can the iterator seek forward: No
 925         #
 926         # We expect iter.can_seek_ns_from_origin to return False.
 927         self._can_seek_ns_from_origin_test(
 928             expected_outcome=False,
 929             user_can_seek_ns_from_origin_ret_val=None,
 930             user_seek_ns_from_origin_provided=False,
 931             iter_can_seek_beginning=True,
 932             iter_can_seek_forward=False,
 933         )
 934
 935     def test_no_can_seek_ns_from_origin_no_seek_ns_from_origin_cant_seek_beginning_forward_seekable(
 936         self,
 937     ):
 938         # Test the case where:
 939         #
 940         #   - can_seek_ns_from_origin: Not provided
 941         #   - seek_ns_from_origin provided: Not provided
 942         #   - can the iterator seek beginning: No
 943         #   - can the iterator seek forward: Yes
 944         #
 945         # We expect iter.can_seek_ns_from_origin to return False.
 946         self._can_seek_ns_from_origin_test(
 947             expected_outcome=False,
 948             user_can_seek_ns_from_origin_ret_val=None,
 949             user_seek_ns_from_origin_provided=False,
 950             iter_can_seek_beginning=False,
 951             iter_can_seek_forward=True,
 952         )
 953
 954     def test_no_can_seek_ns_from_origin_no_seek_ns_from_origin_cant_seek_beginning_not_forward_seekable(
 955         self,
 956     ):
 957         # Test the case where:
 958         #
 959         #   - can_seek_ns_from_origin: Not provided
 960         #   - seek_ns_from_origin provided: Not provided
 961         #   - can the iterator seek beginning: No
 962         #   - can the iterator seek forward: No
 963         #
 964         # We expect iter.can_seek_ns_from_origin to return False.
 965         self._can_seek_ns_from_origin_test(
 966             expected_outcome=False,
 967             user_can_seek_ns_from_origin_ret_val=None,
 968             user_seek_ns_from_origin_provided=False,
 969             iter_can_seek_beginning=False,
 970             iter_can_seek_forward=False,
 971         )
 972
 973     def _can_seek_ns_from_origin_test(
 974         self,
 975         expected_outcome,
 976         user_can_seek_ns_from_origin_ret_val,
 977         user_seek_ns_from_origin_provided,
 978         iter_can_seek_beginning,
 979         iter_can_seek_forward,
 980     ):
 981         class MySink(bt2._UserSinkComponent):
 982             def __init__(self, config, params, obj):
 983                 self._add_input_port("in")
 984
 985             def _user_graph_is_configured(self):
 986                 self._msg_iter = self._create_message_iterator(self._input_ports["in"])
 987
 988             def _user_consume(self):
 989                 nonlocal can_seek_ns_from_origin
 990                 can_seek_ns_from_origin = self._msg_iter.can_seek_ns_from_origin(
 991                     passed_ns_from_origin
 992                 )
 993
 994         if user_can_seek_ns_from_origin_ret_val is not None:
 995
 996             def user_can_seek_ns_from_origin(self, ns_from_origin):
 997                 nonlocal received_ns_from_origin
 998                 received_ns_from_origin = ns_from_origin
 999                 return user_can_seek_ns_from_origin_ret_val
1000
1001         else:
1002             user_can_seek_ns_from_origin = None
1003
1004         if user_seek_ns_from_origin_provided:
1005
1006             def user_seek_ns_from_origin(self, ns_from_origin):
1007                 pass
1008
1009         else:
1010             user_seek_ns_from_origin = None
1011
1012         if iter_can_seek_beginning:
1013
1014             def user_seek_beginning(self):
1015                 pass
1016
1017         else:
1018             user_seek_beginning = None
1019
1020         graph = _setup_seek_test(
1021             MySink,
1022             user_can_seek_ns_from_origin=user_can_seek_ns_from_origin,
1023             user_seek_ns_from_origin=user_seek_ns_from_origin,
1024             user_seek_beginning=user_seek_beginning,
1025             can_seek_forward=iter_can_seek_forward,
1026         )
1027
1028         passed_ns_from_origin = 77
1029         received_ns_from_origin = None
1030         can_seek_ns_from_origin = None
1031         graph.run_once()
1032         self.assertIs(can_seek_ns_from_origin, expected_outcome)
1033
1034         if user_can_seek_ns_from_origin_ret_val is not None:
1035             self.assertEqual(received_ns_from_origin, passed_ns_from_origin)
1036
1037     def test_can_seek_ns_from_origin_user_error(self):
1038         class MySink(bt2._UserSinkComponent):
1039             def __init__(self, config, params, obj):
1040                 self._add_input_port("in")
1041
1042             def _user_graph_is_configured(self):
1043                 self._msg_iter = self._create_message_iterator(self._input_ports["in"])
1044
1045             def _user_consume(self):
1046                 # This is expected to raise.
1047                 self._msg_iter.can_seek_ns_from_origin(2)
1048
1049         def _user_can_seek_ns_from_origin(self, ns_from_origin):
1050             raise ValueError("Joutel")
1051
1052         graph = _setup_seek_test(
1053             MySink,
1054             user_can_seek_ns_from_origin=_user_can_seek_ns_from_origin,
1055             user_seek_ns_from_origin=lambda: None,
1056         )
1057
1058         with self.assertRaises(bt2._Error) as ctx:
1059             graph.run_once()
1060
1061         cause = ctx.exception[0]
1062         self.assertIn("ValueError: Joutel", cause.message)
1063
1064     def test_can_seek_ns_from_origin_wrong_return_value(self):
1065         class MySink(bt2._UserSinkComponent):
1066             def __init__(self, config, params, obj):
1067                 self._add_input_port("in")
1068
1069             def _user_graph_is_configured(self):
1070                 self._msg_iter = self._create_message_iterator(self._input_ports["in"])
1071
1072             def _user_consume(self):
1073                 # This is expected to raise.
1074                 self._msg_iter.can_seek_ns_from_origin(2)
1075
1076         def _user_can_seek_ns_from_origin(self, ns_from_origin):
1077             return "Nitchequon"
1078
1079         graph = _setup_seek_test(
1080             MySink,
1081             user_can_seek_ns_from_origin=_user_can_seek_ns_from_origin,
1082             user_seek_ns_from_origin=lambda: None,
1083         )
1084
1085         with self.assertRaises(bt2._Error) as ctx:
1086             graph.run_once()
1087
1088         cause = ctx.exception[0]
1089         self.assertIn("TypeError: 'str' is not a 'bool' object", cause.message)
1090
1091     def test_seek_ns_from_origin(self):
1092         class MySink(bt2._UserSinkComponent):
1093             def __init__(self, config, params, obj):
1094                 self._add_input_port("in")
1095
1096             def _user_graph_is_configured(self):
1097                 self._msg_iter = self._create_message_iterator(self._input_ports["in"])
1098
1099             def _user_consume(self):
1100                 self._msg_iter.seek_ns_from_origin(17)
1101
1102         def _user_seek_ns_from_origin(self, ns_from_origin):
1103             nonlocal actual_ns_from_origin
1104             actual_ns_from_origin = ns_from_origin
1105
1106         graph = _setup_seek_test(
1107             MySink, user_seek_ns_from_origin=_user_seek_ns_from_origin
1108         )
1109
1110         actual_ns_from_origin = None
1111         graph.run_once()
1112         self.assertEqual(actual_ns_from_origin, 17)
1113
1114
1115 if __name__ == "__main__":
1116     unittest.main()