Merge pull request #322 from mbj/fix/tput-instance

Remove boot time tput initialization

config/flay.yml

@@ -1,3 +1,3 @@
 ---
 threshold: 18
-total_score: 1223
+total_score: 1233

lib/mutant/reporter/cli.rb

@@ -13,9 +13,10 @@ module Mutant
       # @api private
       #
       def self.build(output)
+        tput = Tput.detect
         tty = output.respond_to?(:tty?) && output.tty?
-        format = if !Mutant.ci? && tty && Tput::INSTANCE.available
-          Format::Framed.new(tty:  tty, tput: Tput::INSTANCE)
+        format = if !Mutant.ci? && tty && tput
+          Format::Framed.new(tty:  tty, tput: tput)
         else
           Format::Progressive.new(tty: tty)
         end

lib/mutant/reporter/cli/tput.rb

@@ -3,23 +3,41 @@ module Mutant
     class CLI
       # Interface to the optionally present tput binary
       class Tput
-        include Adamantium, Concord::Public.new(:available, :prepare, :restore)
+        include Adamantium, Concord::Public.new(:prepare, :restore)
 
         private_class_method :new
 
-        capture = lambda do |command|
+        # Return detected tput support
+        #
+        # @return [Tput]
+        #   if tput support is present
+        #
+        # @return [nil]
+        #   otherwise
+        def self.detect
+          reset   = capture('tput reset')
+          save    = capture('tput sc') if reset
+          restore = capture('tput rc') if save
+          clean   = capture('tput ed') if restore
+          new(reset + save, restore + clean) if clean
+        end
+
+        # Capture output
+        #
+        # @param [String] command
+        #   command to run
+        #
+        # @return [String]
+        #   stdout of command on success
+        #
+        # @return [nil]
+        #   otherwise
+        #
+        def self.capture(command)
           stdout, _stderr, exitstatus = Open3.capture3(command)
           stdout if exitstatus.success?
         end
-
-        reset   = capture.('tput reset')
-        save    = capture.('tput sc') if reset
-        restore = capture.('tput rc') if save
-        clean   = capture.('tput ed') if restore
-
-        UNAVAILABLE = new(false, nil, nil)
-
-        INSTANCE = clean ? new(true, reset + save, restore + clean) : UNAVAILABLE
+        private_class_method :capture
 
       end # TPUT
     end # CLI

spec/unit/mutant/reporter/cli/tput_spec.rb

@@ -0,0 +1,38 @@
+RSpec.describe Mutant::Reporter::CLI::Tput do
+  describe '.detect' do
+    subject { described_class.detect }
+
+    def expect_command(command, stdout, success)
+      allow(Open3).to receive(:capture3).with(command).ordered.and_return(
+        [
+          stdout,
+          double('Stderr'),
+          double('Exitstatus', success?: success)
+        ]
+      )
+    end
+
+    let(:tput_reset?) { true }
+    let(:tput_sc?)    { true }
+    let(:tput_rc?)    { true }
+    let(:tput_ed?)    { true }
+
+    before do
+      expect_command('tput reset', '[reset]', tput_reset?)
+      expect_command('tput sc', '[sc]', tput_sc?)
+      expect_command('tput rc', '[rc]', tput_rc?)
+      expect_command('tput ed', '[ed]', tput_ed?)
+    end
+
+    context 'when all tput commands are supported' do
+      its(:prepare) { should eql('[reset][sc]') }
+      its(:restore) { should eql('[rc][ed]')    }
+    end
+
+    context 'when tput reset fails' do
+      let(:tput_reset?) { false }
+
+      it { should be(nil) }
+    end
+  end
+end

spec/unit/mutant/reporter/cli_spec.rb

@@ -4,10 +4,18 @@ RSpec.describe Mutant::Reporter::CLI do
   let(:object) { described_class.new(output, format) }
   let(:output) { StringIO.new                        }
 
+  let(:tput) do
+    double(
+      'tput',
+      restore: '[tput-restore]',
+      prepare: '[tput-prepare]'
+    )
+  end
+
   let(:framed_format) do
     described_class::Format::Framed.new(
       tty:  false,
-      tput: described_class::Tput::UNAVAILABLE
+      tput: tput
     )
   end
 
@@ -43,7 +51,7 @@ RSpec.describe Mutant::Reporter::CLI do
     let(:framed_format) do
       described_class::Format::Framed.new(
         tty:  true,
-        tput: described_class::Tput::INSTANCE
+        tput: tput
       )
     end
 
@@ -56,9 +64,21 @@ RSpec.describe Mutant::Reporter::CLI do
     let(:ci?)    { false                        }
 
     context 'when not on CI and on a tty' do
+      before do
+        expect(described_class::Tput).to receive(:detect).and_return(tput)
+      end
+
+      context 'and tput is available' do
         it { should eql(described_class.new(output, framed_format)) }
       end
 
+      context 'and tput is not available' do
+        let(:tput) { nil }
+
+        it { should eql(described_class.new(output, progressive_format)) }
+      end
+    end
+
     context 'when on CI' do
       let(:ci?) { true }
       it { should eql(described_class.new(output, progressive_format)) }
@@ -109,7 +129,7 @@ RSpec.describe Mutant::Reporter::CLI do
     end
 
     context 'on framed format' do
-      it_reports ''
+      it_reports '[tput-prepare]'
     end
   end
 
@@ -144,7 +164,7 @@ RSpec.describe Mutant::Reporter::CLI do
         update(:env_result) { { subject_results: [] } }
 
         it_reports <<-REPORT
-          Mutant configuration:
+          [tput-restore]Mutant configuration:
           Matcher:         #<Mutant::Matcher::Config match_expressions=[] subject_ignores=[] subject_selects=[]>
           Integration:     null
           Expect Coverage: 100.00%
@@ -169,7 +189,7 @@ RSpec.describe Mutant::Reporter::CLI do
           update(:status) { { active_jobs: [].to_set } }
 
           it_reports(<<-REPORT)
-            Mutant configuration:
+            [tput-restore]Mutant configuration:
             Matcher:         #<Mutant::Matcher::Config match_expressions=[] subject_ignores=[] subject_selects=[]>
             Integration:     null
             Expect Coverage: 100.00%
@@ -196,7 +216,7 @@ RSpec.describe Mutant::Reporter::CLI do
             update(:mutation_a_test_result) { { passed: true } }
 
             it_reports(<<-REPORT)
-              Mutant configuration:
+              [tput-restore]Mutant configuration:
               Matcher:         #<Mutant::Matcher::Config match_expressions=[] subject_ignores=[] subject_selects=[]>
               Integration:     null
               Expect Coverage: 100.00%
@@ -224,7 +244,7 @@ RSpec.describe Mutant::Reporter::CLI do
 
           context 'on success' do
             it_reports(<<-REPORT)
-              Mutant configuration:
+              [tput-restore]Mutant configuration:
               Matcher:         #<Mutant::Matcher::Config match_expressions=[] subject_ignores=[] subject_selects=[]>
               Integration:     null
               Expect Coverage: 100.00%