add new profiler class

Author: JonRowe

lib/rspec/core.rb

@@ -31,6 +31,7 @@
   option_parser
   configuration_options
   runner
+  profiler
   example
   shared_example_group
   example_group

lib/rspec/core/configuration.rb

@@ -827,6 +827,18 @@ def profile_examples
         end
       end
 
+      # @private
+      def profiler
+        @profiler ||=
+          begin
+            if value_for(:profile_examples) { @profile_examples }
+              Profiler.new
+            else
+              NoProfiler.new
+            end
+          end
+      end
+
       # @private
       def files_or_directories_to_run=(*files)
         files = files.flatten

lib/rspec/core/profiler.rb

@@ -0,0 +1,38 @@
+module RSpec
+  module Core
+    # @private
+    class NoProfiler
+      def example_groups
+        {}
+      end
+    end
+
+    # @private
+    class Profiler
+      Formatters.register self, :example_group_started, :example_group_finished, :example_started
+
+      def initialize
+        @example_groups = {}
+      end
+
+      attr_reader :example_groups
+
+      def example_group_started(notification)
+        @example_groups[notification.group.id] = Hash.new(0)
+        @example_groups[notification.group.id][:start] = Time.now
+        @example_groups[notification.group.id][:description] = notification.group.top_level_description
+      end
+
+      def example_group_finished(notification)
+        @example_groups[notification.group.id][:total_time] =  Time.now - @example_groups[notification.group.id][:start]
+      end
+
+      def example_started(notification)
+        #todo: maybe move example_group.parent_groups.last to an example or notification method like example.last_anscestor_groupdd
+        group = notification.example.example_group.parent_groups.last.id
+        @example_groups[group][:count] += 1
+      end
+
+    end
+  end
+end

lib/rspec/core/reporter.rb

@@ -18,6 +18,7 @@ def initialize(configuration)
       @failed_examples = []
       @pending_examples = []
       @duration = @start = @load_time = nil
+      register_listener @configuration.profiler, *Formatters::Loader.formatters[@configuration.profiler.class]
     end
 
     # @private

spec/rspec/core/profiler_spec.rb

@@ -0,0 +1,78 @@
+require 'rspec/core/profiler'
+
+RSpec.describe 'RSpec::Core::NoProfiler' do
+  let(:no_profiler) { RSpec::Core::NoProfiler.new }
+
+  it 'has an empty hash of example_groups' do
+    expect(no_profiler.example_groups).to be_empty.and be_a Hash
+  end
+end
+
+RSpec.describe 'RSpec::Core::Profiler' do
+  let(:profiler) { RSpec::Core::Profiler.new }
+
+  it 'has starts with an empty hash of example_groups' do
+    expect(profiler.example_groups).to be_empty.and be_a Hash
+  end
+
+  context 'when hooked into the reporter' do
+    include FormatterSupport
+
+    let(:id) { 42 }
+    let(:description ) { "My Group" }
+    let(:now) { ::Time.now }
+
+    before do
+      allow(::RSpec::Core::Time).to receive(:now) { now }
+    end
+
+    def group
+      @group ||=
+        begin
+          group = super
+          allow(group).to receive_messages(id: id, top_level_description: description)
+          group
+        end
+    end
+
+    describe '#example_group_started' do
+      it 'records example groups start time and description via id' do
+        expect {
+          profiler.example_group_started group_notification group
+        }.to change { profiler.example_groups[id] }.to include(
+          start: now, description: description
+        )
+      end
+    end
+
+    describe '#example_group_finished' do
+      before do
+        profiler.example_group_started group_notification group
+        allow(::RSpec::Core::Time).to receive(:now) { now + 1 }
+      end
+
+      it 'records example groups total time and description via id' do
+        expect {
+          profiler.example_group_finished group_notification group
+        }.to change { profiler.example_groups[id] }.to include(
+          total_time: 1.0
+        )
+      end
+    end
+
+    describe '#example_started' do
+      let(:example) { new_example }
+      before do
+        allow(example).to receive(:example_group) { group }
+        allow(group).to receive(:parent_groups) { [group] }
+        profiler.example_group_started group_notification group
+      end
+
+      it 'increments the count of examples for its parent group' do
+        expect {
+          profiler.example_started example_notification example
+        }.to change { profiler.example_groups[id][:count] }.by 1
+      end
+    end
+  end
+end