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#    http://www.apache.org/licenses/LICENSE-2.0
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"""Tests for apache_beam.runners.interactive.interactive_environment."""
from __future__ import absolute_import

import importlib
import unittest

from apache_beam.runners.interactive import interactive_environment as ie

# The module name is also a variable in module.
_module_name = 'apache_beam.runners.interactive.interactive_environment_test'


class InteractiveEnvironmentTest(unittest.TestCase):

  def setUp(self):
    self._var_in_class_instance = 'a var in class instance'
    ie.new_env()

  def assertVariableWatched(self, variable_name, variable_val):
    self.assertTrue(self._is_variable_watched(variable_name, variable_val))

  def assertVariableNotWatched(self, variable_name, variable_val):
    self.assertFalse(self._is_variable_watched(variable_name, variable_val))

  def _is_variable_watched(self, variable_name, variable_val):
    return any([(variable_name, variable_val) in watching for watching in
                ie.current_env().watching()])

  def _a_function_with_local_watched(self):
    local_var_watched = 123  # pylint: disable=unused-variable
    ie.current_env().watch(locals())

  def _a_function_not_watching_local(self):
    local_var_not_watched = 456  # pylint: disable=unused-variable

  def test_watch_main_by_default(self):
    self.assertTrue('__main__' in ie.current_env()._watching_set)
    # __main__ module has variable __name__ with value '__main__'
    self.assertVariableWatched('__name__', '__main__')

  def test_watch_a_module_by_name(self):
    self.assertFalse(
        _module_name in ie.current_env()._watching_set)
    self.assertVariableNotWatched('_module_name', _module_name)
    ie.current_env().watch(_module_name)
    self.assertTrue(
        _module_name in
        ie.current_env()._watching_set)
    self.assertVariableWatched('_module_name', _module_name)

  def test_watch_a_module_by_module_object(self):
    module = importlib.import_module(_module_name)
    self.assertFalse(module in ie.current_env()._watching_set)
    self.assertVariableNotWatched('_module_name', _module_name)
    ie.current_env().watch(module)
    self.assertTrue(module in ie.current_env()._watching_set)
    self.assertVariableWatched('_module_name', _module_name)

  def test_watch_locals(self):
    self.assertVariableNotWatched('local_var_watched', 123)
    self.assertVariableNotWatched('local_var_not_watched', 456)
    self._a_function_with_local_watched()
    self.assertVariableWatched('local_var_watched', 123)
    self._a_function_not_watching_local()
    self.assertVariableNotWatched('local_var_not_watched', 456)

  def test_watch_class_instance(self):
    self.assertVariableNotWatched('_var_in_class_instance',
                                  self._var_in_class_instance)
    ie.current_env().watch(self)
    self.assertVariableWatched('_var_in_class_instance',
                               self._var_in_class_instance)


if __name__ == '__main__':
  unittest.main()