Possibly bug in calculating diffs

[attila0x2A]

When running coala with following .coafile:

[python]
bears = PEP8Bear
files = py.py

the py.py content:

def helloWorld():




    return(print("hello World"))

 #s

helloWorld()

coala proposes two diffs instead of one, which doesn't feel right. Here are the diff. First:

|   1|   1| def helloWorld():
|   2|   2| 
|    |   3|+    return(print("hello World"))
|   3|   4| 
|   4|   5| 
|   5|   6| 

Second:

|   1|   1| def helloWorld():
|   2|   2| 
|   3|   3| 
|   4|    |-
|   5|    |-
|   6|    |-    return(print("hello World"))
|   7|    |-
|   8|    |- #s
|    |   4|+ # s
|   9|   5| 
|  10|   6| helloWorld()

Somehow I think this should be only one diff.
The problem may be with PEP8Bear, so that's why I'm opening it here.

[gitmate-bot]

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CC @sils1297, @AbdealiJK

[Makman2]

We use Diff.split_diff() to part up a single big diff. Indeed your example demonstrates that sometimes this is weak^^
Maybe it's possible to group issues that belong together inside a diff with PEP8?

[attila0x2A]

It may be a problem not only with PEP8. By the way, @Makman2 can you reproduce this. There is still a chance that I have outdated coala version or something.

[sils]

No this is definitely the case, we sadly can't do more than either split the diff or not split it at all. Well,we could allow say 2ish lines unchanged for the hunks to remain in the same diff?

This definitely applies to other bears too

[sils]

I have introduced a distance parameter in coala that allows seperating diffs only if they're further away than n lines, we should make use of this in various bears.

[jack17529]

Can I assign this to me as I have not done anything in coala-bear

[Makman2]

Cause of coala/coala#2898.

[Makman2]

@jack17529 feel free to break this issue up into several smaller issues for each bear you find you can improve 👍

[Naveenaidu]

@Makman2 Can i please be assigned to this issue.