Replacement Options File Parser

[TomNicholas]

I'm trying to write a replacement BOUT Options File Parser to replace the boutdata.BoutOptionsFile class, which solves the issues in #94. The biggest difference is that this version has lots of tests.

Due to the bespoke structure of BOUT.inp files, I've ended up writing it from scratch, taking a lot of inspiration from the old class. For BOUT v5 I think the options file format should be changed to follow YAML strictly, but this is for until then.

Currently a work-in-progress, but feedback is welcome.

[pep8speaks]

Hello @TomNicholas! Thanks for updating this PR. We checked the lines you've touched for PEP 8 issues, and found:

• In the file xbout/options.py:

Line 16:90: E501 line too long (93 > 89 characters)
Line 52:24: E701 multiple statements on one line (colon)
Line 229:13: E117 over-indented (comment)
Line 230:13: E117 over-indented (comment)
Line 233:13: E117 over-indented (comment)
Line 234:13: E117 over-indented (comment)
Line 308:13: E265 block comment should start with '# '

• In the file xbout/tests/test_options.py:

Line 118:1: W293 blank line contains whitespace
Line 174:1: E305 expected 2 blank lines after class or function definition, found 1
Line 219:90: E501 line too long (91 > 89 characters)
Line 244:63: E712 comparison to True should be 'if cond is True:' or 'if cond:'
Line 291:5: E265 block comment should start with '# '
Line 292:5: E265 block comment should start with '# '
Line 307:19: W291 trailing whitespace
Line 314:90: E501 line too long (90 > 89 characters)
Line 325:90: E501 line too long (93 > 89 characters)
Line 334:90: E501 line too long (92 > 89 characters)
Line 338:90: E501 line too long (98 > 89 characters)
Line 339:48: E261 at least two spaces before inline comment
Line 339:49: E262 inline comment should start with '# '
Line 342:90: E501 line too long (94 > 89 characters)

Comment last updated at 2020-01-07 11:30:47 UTC

[codecov-io]

Codecov Report

Merging #97 into master will increase coverage by 7.94%.
The diff coverage is 93.06%.

@@            Coverage Diff             @@
##           master      #97      +/-   ##
==========================================
+ Coverage   47.89%   55.83%   +7.94%     
==========================================
  Files          11       12       +1     
  Lines        1069     1490     +421     
  Branches      214      354     +140     
==========================================
+ Hits          512      832     +320     
- Misses        496      568      +72     
- Partials       61       90      +29

Impacted Files	Coverage Δ
xbout/boutdataset.py	68.8% <100%> (+1.41%)	⬆️
xbout/options.py	93% <93%> (ø)
xbout/plotting/animate.py	44% <0%> (+1.03%)	⬆️
xbout/boutdataarray.py	65.78% <0%> (+2.82%)	⬆️
xbout/load.py	79.72% <0%> (+4.21%)	⬆️

---

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[ZedThree]

BOUT++ has dropped support for ; as a comment character, I doubt you'll come across an input file that uses them