964506 - [mozprocess] ProcessHandlerMixin's processOutputLine parameter may accept a function according to the docstring, while in fact it only accepts arrays

Status: RESOLVED FIXED

(Testing :: Mozbase, defect)

Description

[dadel]

User Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:26.0) Gecko/20100101 Firefox/26.0 (Beta/Release)
Build ID: 20131206151436

Steps to reproduce:

The mozprocess module provides ProcessHandler to launch commands.
As the documentation says (https://mozbase.readthedocs.org/en/latest/mozprocess.html), the parameter processOutputLine allow to provide a function to be called for each line of output.
According to this, the following code should work:

from mozprocess import processhandler
def output(l):
    print ("#> "+str(l))

p = processhandler.ProcessHandler(COMMAND_TO_LAUNCH,
                                  cwd='./',processOutputLine=output)
p.run()
print p.wait()



Actual results:

An AttributeError exception is raised showing that in fact an array is expected as following:

  File "/.../src/mozbase/mozprocess/mozprocess/processhandler.py", line 911, in __init__
    kwargs['processOutputLine'].append(storeoutput)
AttributeError: 'function' object has no attribute 'append'



Expected results:

According to the documentation, a single function should be accepted instead of an array and the previous code exemple shouldn't fail.

Comment 1

[dadel]

Note that ProcessHandler is a wrapper for ProcessHandlerMixin. And using directly ProcessHandlerMixin, will also lead to an exception due to the same problem:

  File "/.../src/mozbase/mozprocess/mozprocess/processhandler.py", line 595, in __init__
    self.processOutputLineHandlers = list(processOutputLine)
TypeError: 'function' object is not iterable

Comment 2

[dadel]

Attachment: Fix both the docstrings and the code to accept single function or array of functions

The patch fix the docstrings and code of both ProcessHandlerMixin and ProcessHandler to accept single function as well as array of functions in processOutputLine

Comment 3

[William Lachance (:wlach)]

Comment on attachment 8366291 [details] [diff] [review]
Fix both the docstrings and the code to accept single function or array of functions

Review of attachment 8366291 [details] [diff] [review]:
-----------------------------------------------------------------

Looks good to me!

Comment 4

[William Lachance (:wlach)]

Pushed: https://github.com/mozilla/mozbase/commit/37961da7fd8e2dcb1fdb5dbae5fb701e0599ec3e