Replace Time.now usage with Mutant::Timer.now

Changelog.md

@@ -1,3 +1,7 @@
+# v0.8.20 2018-11-25
+
+* Replace internal timers with monotonic ones.
+
 # v0.8.19 2018-11-06
 
 * Drop support for Ruby < 2.5

lib/mutant/env.rb

@@ -42,7 +42,7 @@ module Mutant
     #
     # rubocop:disable MethodLength
     def run_mutation_tests(mutation)
-      start = Time.now
+      start = Timer.now
       tests = selector.call(mutation.subject)
 
       config.isolation.call do
@@ -53,7 +53,7 @@ module Mutant
       Result::Test.new(
         output:  error.message,
         passed:  false,
-        runtime: Time.now - start,
+        runtime: Timer.now - start,
         tests:   tests
       )
     end

lib/mutant/integration/minitest.rb

@@ -82,7 +82,7 @@ module Mutant
       def call(tests)
         test_cases = tests.map(&all_tests_index.method(:fetch))
         output     = StringIO.new
-        start      = Time.now
+        start      = Timer.now
 
         reporter = ::Minitest::SummaryReporter.new(output)
 
@@ -98,7 +98,7 @@ module Mutant
           passed:  reporter.passed?,
           tests:   tests,
           output:  output.read,
-          runtime: Time.now - start
+          runtime: Timer.now - start
         )
       end
 

lib/mutant/integration/rspec.rb

@@ -61,13 +61,13 @@ module Mutant
       def call(tests)
         examples = tests.map(&all_tests_index.method(:fetch))
         filter_examples(&examples.method(:include?))
-        start = Time.now
+        start = Timer.now
         passed = @runner.run_specs(@world.ordered_example_groups).equal?(EXIT_SUCCESS)
         @output.rewind
         Result::Test.new(
           output:  @output.read,
           passed:  passed,
-          runtime: Time.now - start,
+          runtime: Timer.now - start,
           tests:   tests
         )
       end

lib/mutant/runner/sink.rb

@@ -10,7 +10,7 @@ module Mutant
       # @return [undefined]
       def initialize(*)
         super
-        @start           = Time.now
+        @start           = Timer.now
         @subject_results = {}
       end
 
@@ -20,7 +20,7 @@ module Mutant
       def status
         Result::Env.new(
           env:             env,
-          runtime:         Time.now - @start,
+          runtime:         Timer.now - @start,
           subject_results: @subject_results.values
         )
       end

spec/support/corpus.rb

@@ -79,7 +79,7 @@ module MutantSpec
       #   otherwise
       def verify_mutation_generation
         checkout
-        start = Time.now
+        start = Mutant::Timer.now
 
         options = {
           finish:       method(:finish),
@@ -90,7 +90,7 @@ module MutantSpec
         total = Parallel.map(effective_ruby_paths, options, &method(:count_mutations_and_check_errors))
           .inject(DEFAULT_MUTATION_COUNT, :+)
 
-        took = Time.now - start
+        took = Mutant::Timer.now - start
         puts MUTATION_GENERATION_MESSAGE % [total, took, total / took]
         self
       end

spec/unit/mutant/env_spec.rb

@@ -57,7 +57,7 @@ RSpec.describe Mutant::Env do
         .with(mutation_subject)
         .and_return(tests)
 
-      allow(Time).to receive_messages(now: Time.at(0))
+      allow(Mutant::Timer).to receive(:now).and_return(2.0, 3.0)
     end
 
     context 'when isolation does not raise error' do
@@ -91,7 +91,7 @@ RSpec.describe Mutant::Env do
         Mutant::Result::Test.new(
           output:  'test-error',
           passed:  false,
-          runtime: 0.0,
+          runtime: 1.0,
           tests:   tests
         )
       end

spec/unit/mutant/integration/rspec_spec.rb

@@ -126,7 +126,7 @@ RSpec.describe Mutant::Integration::Rspec do
       .and_return(rspec_runner)
 
     expect(RSpec).to receive_messages(world: world)
-    allow(Time).to receive_messages(now: Time.now)
+    allow(Mutant::Timer).to receive_messages(now: Mutant::Timer.now)
   end
 
   describe '#all_tests' do

spec/unit/mutant/reporter/cli_spec.rb

@@ -41,7 +41,7 @@ RSpec.describe Mutant::Reporter::CLI do
   end
 
   before do
-    allow(Time).to receive(:now).and_return(Time.now)
+    allow(Mutant::Timer).to receive_messages(now: Mutant::Timer.now)
   end
 
   describe '.build' do

spec/unit/mutant/runner/sink_spec.rb

@@ -19,7 +19,7 @@ describe Mutant::Runner::Sink do
   let(:object) { described_class.new(env) }
 
   before do
-    allow(Time).to receive(:now).and_return(Time.now)
+    allow(Mutant::Timer).to receive_messages(now: Mutant::Timer.now)
   end
 
   describe '#result' do