Test coverage drop when upgrading to 0.11.2 from 0.10.0

[David-Sharpe]

When upgrading from simplecov 0.10.0 to 0.11.2 our code coverage drops significantly. We go from 100% to 87.67%.

This is the result set from the 100% test coverage simplecov 0.10.0 run.
resultset_0_10.txt

This is the result set from the 87.67%
resultset_0_11.txt

The only difference between these two runs is the upgrade to simplecov 0.11.2 and running bundle.
I have noticed some files are in more sections with the newer version. For example, a file may show up in 1 and 2 of 4 in the 0_10 result set instead of just 1 of 4 in the 0_11 result set. The additional entries seem to have all lines as 0's. I'm guessing these extra all 0 entries are driving down the test coverage during the merge.

ruby 2.0.0p481 (2014-05-08 revision 45883) [x86_64-darwin14.3.0]
Rails 4.1
RSpec 3.4.1
We are using parallel_tests 1.5.1 with 4 threads.
Tests are invoked with rake parallel:spec[4]

We are not using a .simplecov file.

[David-Sharpe]

Problem comes from track_files. Setting track_files to false in spec_helper in the SimpleCov.start 'rails' block fixes this.

[rdunlop]

@David-Sharpe Could this be caused by #441 ?

[wkirby]

@David-Sharpe Setting track_files to false excludes all files with 0% coverage from the report, arbitrarily inflating our coverage metrics. Not including track_files false shows no ops as not being covered, deflating our coverage metrics.

What is the option for getting accurate coverage metrics?

[PragTob]

This should be fixed with the recent merge of the track files fix, if not please let us know