class_docstr: Tests for verifying ProgressHooks.
      
class_docstr_tok: ["Tests","for","verifying","ProgressHooks","."]
code: def test_progress_hooks_empty_pipeline(self):
      publisher = TestingProgressPublisher()
      hooks = [ProgressHooks.with_static_publisher(publisher)]
      pipeline = Pipeline({}, domain=US_EQUITIES)
      start_date, end_date = self.trading_days[[-10, -1]]
      expected_chunks = [
          tuple(self.trading_days[[-10, -6]]),
          tuple(self.trading_days[[-5, -1]]),
      ]
  
      self.run_chunked_pipeline(
          pipeline=pipeline,
          start_date=start_date,
          end_date=end_date,
          chunksize=5,
          hooks=hooks,
      )
  
      self.verify_trace(
          publisher.trace,
          pipeline_start_date=start_date,
          pipeline_end_date=end_date,
          expected_chunks=expected_chunks,
          empty=True,
      )
  
imports: import itertools
  from operator import attrgetter
  import numpy
  import pandas
  import toolz
  from zipline.pipeline import Pipeline
  from zipline.pipeline.classifiers import Everything
  from zipline.pipeline.domain import US_EQUITIES
  from zipline.pipeline.factors import CustomFactor
  from zipline.pipeline.data import Column, DataSet
  from zipline.pipeline.data.testing import TestingDataSet
  from zipline.pipeline.hooks.testing import TestingHooks
  from zipline.pipeline.hooks.progress import ProgressHooks, repr_htmlsafe, TestingProgressPublisher
  from zipline.pipeline.term import AssetExists, ComputableTerm, LoadableTerm
  from zipline.testing import parameter_space
  from zipline.testing.fixtures import ZiplineTestCase, WithSeededRandomPipelineEngine
  from zipline.testing.predicates import assert_almost_equal, instance_of
label_desc: Use image node_id 4 for calling the ProgressHooksTestCase obj's underlying member method code with example usage: obj.test_progress_hooks_empty_pipeline() without return types