Improve Stan Parser

[gowerc]

Closes #97

@danielinteractive

• As discussed in the issue the code has been altered to improve error handling for known problem cases (1-line blocks)
• I started the "extending jmpost" vignette which provides details of our rules for Stan file formatting
• Fixed a bug with the StanModule print message that was displaying spurious blocks (I separated this into its own commit if you want to review that independently).
• There were also a couple of minor / edge case bug fixes to the parser around how it handles whitespace on the closing } (e.g. just made the regex more robust)
• Heavily commented the function as its pretty difficult to understand by skimming the code alone.

[github-actions]

Unit Tests Summary

    1 files    34 suites   1m 56s ⏱️
  98 tests   74 ✔️ 24 💤 0 ❌
337 runs  313 ✔️ 24 💤 0 ❌

Results for commit d57f738.

♻️ This comment has been updated with latest results.

[github-actions]

Code Coverage Summary

Filename                       Stmts    Miss  Cover    Missing
---------------------------  -------  ------  -------  ---------------------------
R/brier_score.R                  166       0  100.00%
R/DataJoint.R                     76       2  97.37%   264, 270
R/DataLongitudinal.R             119       1  99.16%   245
R/DataSubject.R                   69       1  98.55%   124
R/DataSurvival.R                  74       1  98.65%   146
R/defaults.R                      13       7  46.15%   27, 45-84, 111
R/generics.R                      16       1  93.75%   69
R/JointModel.R                    91       8  91.21%   113-125, 204, 210, 216
R/JointModelSamples.R             54       0  100.00%
R/Link.R                          18       0  100.00%
R/LinkGSF.R                       69      13  81.16%   116-128
R/LinkNone.R                       5       1  80.00%   36
R/LinkRandomSlope.R               11       0  100.00%
R/LongitudinalGSF.R               24       0  100.00%
R/LongitudinalModel.R             17       0  100.00%
R/LongitudinalQuantities.R        85       8  90.59%   100-107
R/LongitudinalRandomSlope.R       22       0  100.00%
R/Parameter.R                     14       0  100.00%
R/ParameterList.R                 37       1  97.30%   175
R/Prior.R                        117       0  100.00%
R/Quantities.R                   105       0  100.00%
R/simulations_gsf.R               43       0  100.00%
R/simulations_os.R                11       5  54.55%   35-39
R/simulations_rs.R                21       0  100.00%
R/simulations.R                   99       1  98.99%   122
R/StanModel.R                     14       0  100.00%
R/StanModule.R                   175       6  96.57%   197-198, 240, 251, 386, 414
R/SurvivalExponential.R           10       0  100.00%
R/SurvivalLoglogistic.R           11       0  100.00%
R/SurvivalModel.R                 19       0  100.00%
R/SurvivalQuantities.R           151       6  96.03%   173-178
R/SurvivalWeibullPH.R             11       0  100.00%
R/utilities.R                    145       1  99.31%   13
R/zzz.R                           11      11  0.00%    4-29
TOTAL                           1923      74  96.15%

Diff against main

Filename          Stmts    Miss  Cover
--------------  -------  ------  -------
R/StanModule.R      +17      +2  -0.90%
TOTAL               +17      +2  -0.07%

Results for commit: d57f738

Minimum allowed coverage is 80%

♻️ This comment has been updated with latest results

[danielinteractive]

Thanks @gowerc , looks very good!