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)
* Nuke around 800 lock
* Honor LSP with not anymore squeezing something non LSP compatible in
the same inheritance tree.
* Separate running from result tree.
* Clean up kill logic and early exits on already dead mutations.
* Fix #runnin? smell for reporters.
* Decouple config object from VM state. Makes it serializable to enable
config loading.
* Fix sequence of global VM events to match PRIOR rspec infects VM with
gazillions of classes / modules. Thix fixes a startup speed
degeneration.
* Various fixes to enhance determinism.
* Replace some unneded manual double dispatch with single manual dispatch for
reporter / runners.
* Add Mutant::AST namespace to hold all AST related data / helpers.
* Mutant::AST will be externalized into an ast-meta gem that can be
shared with unparser for deduplication.
* Over the time the mutators itself will not need to deal with semantic
analysis of the AST anymore by themselves.
* Move AST analysis for send nodes to AST::Meta
* Fix#209
