Tag: Programming

Unsafe Chrome Sometimes Necessary

In my work – every now and then – I found myself in need of a browser with reduced security checks (mainly to gloss over cross domain XMLHttpRequests and SSL certificate violations) for testing purposes. I didn’t want to take the risk and use my main browser session with these settings, so I made me a script (also available as a Gist). 🙂

Tip:
If you use oh my ZSH you can save this file in 

~/.oh-my-zsh/custom/plugins/chrome-unsafe/chrome-unsafe.plugin.zsh

and add “chrome-unsafe” to your list of used plugins in 

~/.zshrc

 

Summing Booleans For Fun And Profit

I came up with a IMHO nice piece of code while working with and getting to know Python.

incomplete_items = [
    item.quantity_ordered > item.quantity_delivered for item in order.items
]
if any(incomplete_items):
    do_something()

This feels clean and obvious. It might not be very efficient though. :/

has_incomplete_items = sum(
    item.quantity_ordered > item.quantity_delivered for item in order.items
)
if has_incomplete_items:
    do_something()

Doing it this way can be more efficient, since it can leverage generators and doesn’t need to go through the list again with 

any

. But using 

sum

  over booleans feels hackish and non-obvious … 🙁

MagicMock With Spec

Thanks to @immoralist I’ve learned a new Python testing trick. I didn’t know about the “spec” argument for MagicMock. m(
Let’s see an example:

from mock import MagicMock

class SomeModel(object):
    foo = "f**"
    bar = "b**"

m = MagicMock(spec=SomeModel)

Here we create a mock object which mimics the interface of 

SomeModel

  as we would expect, returning mock values for things we access.

>>> m.foo
<MagicMock name='mock.foo' id='4506756880'>
>>> m.bar
<MagicMock name='mock.bar' id='4506754192'>

Let’s see what happens if we call something else:

>>> m.baz
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File ".../env/lib/python2.7/site-packages/mock.py", line 658, in __getattr__
    raise AttributeError("Mock object has no attribute %r" % name)
AttributeError: Mock object has no attribute 'baz'

It will fail loudly while a mock object without a spec would have returned a mock value as it did in the previous example.

But the magic doesn’t end there. You can still set additional attributes/methods “by hand” and have them not fail even if they aren’t part of the original spec.

>>> m.baz = "bazzzzz"
>>> m.baz
'bazzzzz'

Learning new things makes me happy. 😀