Is there some kind of exit statement in Haxe? - haxe

Is there some kind of exit statement in haxe? Like
import sys
sys.exit(0)
in Python or
System.exit(0);
in Java?
P.S.: Only need this for sys targets ...

You can use Sys.exit(code) in sys targets (cpp, cs, hl, java, lua, macro, neko, php, python).
https://api.haxe.org/Sys.html#exit
And for Flash target: flash.system.System.exit(code)
https://api.haxe.org/flash/system/System.html#exit

Related

Python3 Unable to store stdout to variable

My case is a little bit specific. I'm trying to run a Python program using Python for testing purposes. The case is as follows:
# file1.py
print("Hello world")
# file1.test.py
import io
import sys
import os
import unittest
EXPECTED_OUTPUT = "Hello world"
class TestHello(unittest.TestCase):
def test_hello(self):
sio = io.StringIO()
sys.stdout = sio
os.system("python3 path/to/file1.py")
sys.stdout = sys.__stdout__
print("captured value:", sio.getvalue())
self.assertEqual(sio.getvalue(), EXPECTED_STDOUT)
if __name__ == "__main__":
unittest.main()
But nothing ends up in the sio variable. This way and similar ways are introduced online but they don't seem to work for me. My Python version is 3.8.10 but it doesn't really matter if this works better in some other version, I can switch to that.
Note: I know that if I was using an importable object this might be easier, but right now I need to know how to catch the output of another file.
Thanks!
stdout redirection does not work like this - this will change the stdout variable inside your Python process. But by using os.system, you are running another process, that will re-use the same terminal pseudo-files your parent process is using.
If you want to log a subprocess, the way to do it is to use the subprocess modules calls, which allow you to redirect the subprocess output. https://docs.python.org/3/library/subprocess.html
Also, the subprocess won't be able to use a StringIO object from the parent process (it is not an O.S. level object, just an in-process Python object with a write method). The docs above include instructions about using the special object subprocess.PIPE which allows for in-memory communication, or, you can just pass an ordinary filesystem file, which you can read afterwards.

How to suppress ImportWarning in a python unittest script

I am currently running a unittest script which successfully passes the various specified test with a nagging ImportWarning message in the console:
...../lib/python3.6/importlib/_bootstrap.py:219: ImportWarning: can't resolve package from __spec__ or __package__, falling back on __name__ and __path__
return f(*args, **kwds)
....
----------------------------------------------------------------------
Ran 7 tests in 1.950s
OK
The script is run with this main function:
if __name__ == '__main__':
unittest.main()
I have read that warnings can be surpressed when the script is called like this:
python -W ignore:ImportWarning -m unittest testscript.py
However, is there a way of specifying this ignore warning in the script itself so that I don't have to call -W ignore:ImportWarning every time that the testscript is run?
Thanks in advance.
To programmatically prevent such warnings from showing up, adjust your code so that:
import warnings
if __name__ == '__main__':
with warnings.catch_warnings():
warnings.simplefilter('ignore', category=ImportWarning)
unittest.main()
Source: https://stackoverflow.com/a/40994600/328469
Update:
#billjoie is certainly correct. If the OP chooses to make answer 52463661 the accepted answer, I am OK with that. I can confirm that the following is effective at suppressing such warning messages at run-time using python versions 2.7.11, 3.4.3, 3.5.4, 3.6.5, and 3.7.1:
#! /usr/bin/env python
# -*- coding: utf-8 -*-
import unittest
import warnings
class TestPandasImport(unittest.TestCase):
def setUp(self):
warnings.simplefilter('ignore', category=ImportWarning)
def test_01(self):
import pandas # noqa: E402
self.assertTrue(True)
def test_02(self):
import pandas # noqa: E402
self.assertFalse(False)
if __name__ == '__main__':
unittest.main()
However, I think that the OP should consider doing some deeper investigation into the application code targets of the unit tests, and try to identify the specific package import or operation which is causing the actual warning, and then suppress the warning as closely as possible to the location in code where the violation takes place. This will obviate the suppression of warnings throughout the entirety of one's unit test class, which may be inadvertently obscuring warnings from other parts of the program.
Outside the unit test, somewhere in the application code:
with warnings.catch_warnings():
warnings.simplefilter('ignore', category=ImportWarning)
# import pandas
# or_ideally_the_application_code_unit_that_imports_pandas()
It could take a bit of work to isolate the specific spot in the code that is either causing the warning or leveraging third-party software which causes the warning, but the developer will obtain a clearer understanding of the reason for the warning, and this will only improve the overall maintainability of the program.
I had the same problem, and starting my unittest script with a warnings.simplefilter() statement, as described by Nels, dit not work for me. According to this source, this is because:
[...] as of Python 3.2, the unittest module was updated to use the warnings module default filter when running tests, and [...] resets to the default filter before each test, meaning that any change you may think you are making scriptwide by using warnings.simplefilter(“ignore”) at the beginning of your script gets overridden in between every test.
This same source recommends to renew the filter inside of each test function, either directly or with an elegant decorator. A simpler solution is to define the warnings filter inside unittest's setUp() method, which is run right before each test.
import unittest
class TestSomething(unittest.TestCase):
def setUp(self):
warnings.simplefilter('ignore', category=ImportWarning)
# Other initialization stuff here
def test_a(self):
# Test assertion here.
if __name__ == '__main__':
unittest.main()
I had the same warning in Pycharm for one test when using unittest. This warning disappeared when I stopped trying to import a library during the test (I moved the import to the top where it's supposed to be). I know the request was for suppression, but this would also make it disappear if it's only happening in a select number of tests.
Solutions with def setUp suppress warnings for all methods within class. If you don't want to suppress it for all of them, you can use decorator.
From Neural Dump:
def ignore_warnings(test_func):
def do_test(self, *args, **kwargs):
with warnings.catch_warnings():
warnings.simplefilter("ignore")
test_func(self, *args, **kwargs)
return do_test
Then you can use it to decorate single test method in your test class:
class TestClass(unittest.TestCase):
#ignore_warnings
def test_do_something_without_warning()
self.assertEqual(whatever)
def test_something_else_with_warning()
self.assertEqual(whatever)

Is there a way to programmatically clear the terminal across platforms in Python 3?

Long-time lurker, first time asker.
Is there a way to automatically clear the terminal in Python 3 regardless of what platform the app is being used in?
I've come across the following (from this answer) which utilises ANSI escape codes:
import sys
sys.stderr.write("\x1b[2J\x1b[H")
But for it to work cross-platform it requires the colorama module which appears to only work on python 2.7.
For context I'm learning Python by building a game of battleships, but after each guess I want to be able to clear the screen and re-print the board.
Any help is appreciated!
Cheers
I use a single snippet for all the platforms:
import subprocess
clear = lambda: subprocess.call('cls' if os.name=='nt' else 'clear')
clear()
Same idea but with a spoon of syntactic sugar:
import subprocess
clear = lambda: subprocess.call('cls||clear', shell=True)
clear()
I know of this method
import os
clear = lambda: os.system('cls')
clear()
I'm not sure if it works with other platforms, but it's working in windows python 3.x
import os
clear = lambda: os.system('clear')
clear()
That might work for linux and OS X, but I can't test.

Cross-platform screenshot in Python 3

There are quite a few questions like this one, but none of them seem to be both cross-platform and specifically for Python 3, and I'm struggling to find a reliable solution.
How can I take a cross-platform screenshot in Python 3?
My current solution has been to use the ImageGrab function from the PIL library, like so:
from PIL import ImageGrab
image = ImageGrab.grab()
You can use platform.system() to find the current OS, and then use a different solution depending on the operating system:
import platform
if platform.system()=="Windows":
...
elif platform.system()=="Darwin": #Mac
...
elif plarform.system()=="Linux":
...
You can use PrtSc Library.
Command : pip3 install PrtSc
Code :
import PrtSc.PrtSc as Screen
screen=Screen.PrtSc(True,"file.png")

how to get down and up interfaces in linux by using python script

from collections import namedtuple
import re
import subprocess
def get_interfaces(external=False, ip=False):
pass
I am new with Python and was hoping someone could help me:
Create an interface.
find down and up interfaces in Linux by using a python script.
As far as I know, there is no standard library in python to manage network interfaces.
The standard tool under Linux is ip. You can wrap it using subprocess. Like this :
import subprocess
for r in subprocess.check_output(["/bin/ip","-o","link"]).split('\n'):
F = r.split(" ")
if len(F)>1:
z=zip(F,F[1:])
s= filter(lambda (k,v): k=="state", z)
print z[0][1][:-1], s[0][1]
Try netifaces, I think it can do exactly what you want
import netifaces
netifaces.interfaces()

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