POC add line numbers

[SpacePossum]

This PR introduces the line numbers to the UnifiedDiffOutputBuilder (finally ;) )

However there a few things to consider;

• the warning inserted about line break differences cause the output of the output builder to be not compat with the patch tool
• the output builder does not add the \No newline at end of file to the output when a string has not a line break as last character, making the output not compat with the patch tool
• with above exceptions the output follows the unified diff format, like patch -u and can be consumed like diff -u
• the output is now minimal around the chunks, we might pick a better default;
  for example diff picks 3 lines above and below a changed line ( -u, -U NUM, --unified[=NUM] output NUM (default 3) lines of unified context)
• above might be a valuable option to be passed through the constructor to allow more tweaking

I left the incompats because;

• removing a feature that people might like (the warning) is not nice
• the \No newline at end of file is only of value when diff'ing files, and not arbitrary strings as typically done by PHPUnit

I plan on writing a full compat version of the output builder so we can offer it 3rd party.

Let me know what you all think :)

ping @keradus @julienfalque please have a look if you've time

PS.
The last commit contains a test that is prop. best not merged to the repo, but is very handy when debugging.

[codecov-io]

Codecov Report

Merging #64 into master will increase coverage by 0.02%.
The diff coverage is 100%.

@@             Coverage Diff              @@
##             master      #64      +/-   ##
============================================
+ Coverage     99.71%   99.73%   +0.02%     
- Complexity      138      146       +8     
============================================
  Files            10       10              
  Lines           347      377      +30     
============================================
+ Hits            346      376      +30     
  Misses            1        1

Impacted Files	Coverage Δ	Complexity Δ
src/Output/UnifiedDiffOutputBuilder.php	100% <100%> (ø)	26 <15> (+8)	⬆️

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[keradus]

The last commit contains a test that is prop. best not merged to the repo, but is very handy when debugging.

Actually, I would keep it

[sebastianbergmann]

The test in question interacts with the filesystem and assumes that patch is on the path. I think there is value in this as an integration test but it will of course not work on Windows, for instance.

[keradus]

of course it would not. that's why there is require OS
if the diff is suppose to be compatible with unified diff format, there is no better way to check it.

[sebastianbergmann]

Sure; but even on Linux patch might not be available. I want this test, though :)

[keradus]

@SpacePossum , is there anything else in big epic of introducing line numbers ?

[SpacePossum]

@keradus I've nothing major planned left for this.
At the moment I can see some refinements that can be made which I've listed in the description of the PR.
Like to hear what others think about the current state of the package and what features people are missing.
In terms of health, the repo has a near 100% test coverage, CS looks fair, performance and complexity looks good to me based on what the code does.

(thanks for reviewing/merging all btw. :) I'll clean up the test a bit more in the near future )

[sebastianbergmann]

@SpacePossum Are we ready for the 2.0.0 tag?

[keradus]

And are any of those refinements BC breakers ?

[SpacePossum]

since the API has been closed down as it is now (final on the classes) I think all ideas for refinements/additions can be done later without BC breakers.

[sebastianbergmann]

@SpacePossum May I tag 2.0.0? Then the next step is to update PHPUnit etc. to the new API.

[SpacePossum]

@sebastianbergmann lets do it :)
The changes on PHPUnit should be relative easy to do, lemme know if I can help out