Several steps were made to achieve mutant working with Ruby 2.4 without
warnings and spec failures:
* Fix Fixnum deprecation warning
* Update RuboCop to 0.47 and fix offenses
* Relax version requirements on parser gem
* Update diff-lcs to 1.3
* Update rake 11.x -> 12.x
* Update reek 4.5 -> 4.6 (to work with parser 2.4)
* Update json 2.0 -> 2.1
* Update parallel 1.10 -> 1.11
* Update simplecov 0.12 -> 0.14
* Run regexp_parser integration against v0.4.3 (as we requiring this
exact version)
* Update warnings.yml with new whitelist
* Run CircleCI tests on Ruby 2.3 and 2.4 (Bundler.with_clean_env
was causing troubles on new CircleCI 2.0 setup, so it was removed)
* I do not use 1.9.3
* Also keeping them in each file increases mental overhead (true it *can* be autoamted)
* None of the files encodes NON ASCII chars.
* I do not expect it makes any difference, since nobody programmatically
will consume strings generated by mutant under the assumption they are UTF-8 encoded.
* 1.9.3 Users have to deal with the encoding fuckup under ruby anyways.
This avoids situartions where the source contains (begin, other)
nodes that get mutated to (other) where there is no difference in the
source.
Closes#198
