How to use the ipykernel.tests.utils.wait_for_idle function in ipykernel

task:
run:
   echo this is "${i}"
   sleep ${i}

[20]
input: for_each={'i': range(2)}
task:
run:
   echo this aa is "${i}"
   sleep ${i}

"""
            # these should be automatically rerun by the frontend
            long_execute(kc=kc, code=code)
            wait_for_idle(kc)

iopub = kc.iopub_channel
            # create a data frame
            execute(kc=kc, code='''
import numpy as np
mat_var = np.matrix([[1,2],[3,4]])
''')
            clear_channels(iopub)
            execute(kc=kc, code="%use Julia")
            wait_for_idle(kc)
            execute(kc=kc, code="%get mat_var")
            wait_for_idle(kc)
            execute(kc=kc, code="size(mat_var)")
            res = get_display_data(iopub)
            self.assertEqual(res, '(2, 2)')
            execute(kc=kc, code="%use sos")
            wait_for_idle(kc)
            #

def testWith(self):
        '''Test magic with'''
        with sos_kernel() as kc:
            iopub = kc.iopub_channel
            # create a data frame
            execute(kc=kc, code='var = [1, 2, 3, 4]')
            wait_for_idle(kc)
            execute(kc=kc, code='%with R -i var -o m\nm=mean(var)')
            wait_for_idle(kc)
            execute(kc=kc, code="%dict m")
            res = get_result(iopub)
            self.assertEqual(res['m'], 2.5)
            execute(kc=kc, code="%use sos")
            wait_for_idle(kc)

def testCD(self):
        with sos_kernel() as kc:
            iopub = kc.iopub_channel
            execute(kc=kc, code="%cd ..")
            wait_for_idle(kc)
            execute(kc=kc, code="import os\nprint(os.getcwd())")
            stdout, stderr = get_std_output(iopub)
            self.assertFalse(stdout.strip().endswith('jupyter'))
            self.assertEqual(stderr, '')
            execute(kc=kc, code="%cd jupyter")

def testRerun(self):
        with sos_kernel() as kc:
            iopub = kc.iopub_channel
            execute(kc=kc, code='''
%run
parameter: a=10

[default]
b = a
''')
            wait_for_idle(kc)
            #
            execute(kc=kc, code='''
%rerun --a 20
''')
            wait_for_idle(kc)
            execute(kc=kc, code="b")
            res = get_result(iopub)
            self.assertEqual(res, 20)

iopub = kc.iopub_channel
            # create a data frame
            execute(kc=kc, code='''
%use JavaScript
null_var = null
num_var = 123
num_arr_var = [1, 2, 3]
logic_var = true
logic_arr_var = [true, false, true]
char_var = '1\"23'
char_arr_var = ['1', '2', '3']
list_var = [1, 2, '3']
named_list_var = {a:1, b:2, c:3}
recursive_var = {a:1, b: {c:3, d:'whatever'}}
''')
            wait_for_idle(kc)
            execute(kc=kc, code="""
%put null_var num_var num_arr_var logic_var logic_arr_var char_var char_arr_var list_var named_list_var recursive_var
%dict null_var num_var num_arr_var logic_var logic_arr_var char_var char_arr_var list_var named_list_var recursive_var
""")
            res = get_result(iopub)
            self.assertEqual(res['null_var'], None)
            self.assertEqual(res['num_var'], 123)
            self.assertEqual(res['num_arr_var'], [1,2,3])
            self.assertEqual(res['logic_var'], True)
            self.assertEqual(res['logic_arr_var'], [True, False, True])
            self.assertEqual(res['char_var'], '1"23')
            self.assertEqual(res['char_arr_var'], ['1', '2', '3'])
            self.assertEqual(res['list_var'], [1,2,'3'])
            self.assertEqual(res['named_list_var'], {'a': 1, 'b': 2, 'c': 3})
            self.assertEqual(res['recursive_var'], {'a': 1, 'b': {'c': 3, 'd': 'whatever'}})
            execute(kc=kc, code="%use sos")

execute(kc=kc, code='''
null_var = None
num_var = 123
import numpy
num_arr_var = numpy.array([1, 2, 3])
logic_var = True
logic_arr_var = [True, False, True]
char_var = '1"23'
char_arr_var = ['1', '2', '3']
list_var = [1, 2, '3']
dict_var = dict(a=1, b=2, c='3')
set_var = {1, 2, '3'}
mat_var = numpy.matrix([[1,2],[3,4]])
recursive_var = {'a': {'b': 123}, 'c': True}
''')
            wait_for_idle(kc)
            execute(kc=kc, code='''
%use JavaScript
%get null_var num_var num_arr_var logic_var logic_arr_var char_var char_arr_var mat_var set_var list_var dict_var recursive_var
%dict -r
%put null_var num_var num_arr_var logic_var logic_arr_var char_var char_arr_var mat_var set_var list_var dict_var recursive_var
%use sos
%dict null_var num_var num_arr_var logic_var logic_arr_var char_var char_arr_var mat_var set_var list_var dict_var recursive_var
''')
            res = get_result(iopub)
            self.assertEqual(res['null_var'], None)
            self.assertEqual(res['num_var'], 123)
            self.assertEqual(res['num_arr_var'], [1,2,3])
            self.assertEqual(res['logic_var'], True)
            self.assertEqual(res['logic_arr_var'], [True, False, True])
            self.assertEqual(res['char_var'], '1"23')
            self.assertEqual(res['char_arr_var'], ['1', '2', '3'])

import pandas as pd
import numpy as np
arr = np.random.randn(1000)
arr[::10] = np.nan
df = pd.DataFrame({'column_{0}'.format(i): arr for i in range(10)})
''')
            clear_channels(iopub)
            execute(kc=kc, code="%use Julia")
            wait_for_idle(kc)
            execute(kc=kc, code="%get df")
            wait_for_idle(kc)
            execute(kc=kc, code="size(df)")
            res = get_display_data(iopub)
            self.assertEqual(res, '(1000, 10)')
            execute(kc=kc, code="%use sos")
            wait_for_idle(kc)

def testHelp(self):
        '''Test help messages'''
        with sos_kernel() as kc:
            # create a data frame
            execute(kc=kc, code='\n'.join('%{} -h'.format(magic) for magic in (
                'cd', 'debug', 'dict', 'get', 'matplotlib', 'paste', 'preview',
                'put', 'render', 'rerun', 'run', 'save', 'sandbox', 'set',
                'sessioninfo', 'sosrun', 'sossave', 'shutdown', 'taskinfo', 'tasks',
                'toc', 'use', 'with', 'pull', 'push')))
            wait_for_idle(kc)

import pandas as pd
import numpy as np
arr = np.random.randn(1000)
arr[::10] = np.nan
df = pd.DataFrame({'column_{0}'.format(i): arr for i in range(10)})
''')
            clear_channels(iopub)
            execute(kc=kc, code="%use R")
            wait_for_idle(kc)
            execute(kc=kc, code="%get df")
            wait_for_idle(kc)
            execute(kc=kc, code="dim(df)")
            res = get_display_data(iopub)
            self.assertEqual(res, '[1] 1000   10')
            execute(kc=kc, code="%use sos")
            wait_for_idle(kc)
            #