Add Map concept so we can customize the way how & when we dump the ma…

…p to our storage

.rubocop.yml

@@ -0,0 +1,5 @@
+AllCops:
+  DisplayCopNames: true
+  TargetRubyVersion: 2.3
+Style/GuardClause:
+  Enabled: false

crystalball.gemspec

@@ -31,6 +31,8 @@ Gem::Specification.new do |spec|
 
   spec.add_dependency 'git'
 
+  spec.required_ruby_version = '> 2.3.0'
+
   spec.add_development_dependency "bundler", "~> 1.14"
   spec.add_development_dependency "rake", "~> 10.0"
   spec.add_development_dependency "rspec", "~> 3.0"

lib/crystalball.rb

@@ -4,6 +4,8 @@
 require 'crystalball/predictor'
 require 'crystalball/execution_detector'
 require 'crystalball/case_map'
+require 'crystalball/map_generator/simple_map'
+require 'crystalball/map_generator/standard_map'
 require 'crystalball/map_generator'
 require 'crystalball/version'
 

lib/crystalball/map_generator.rb

@@ -10,11 +10,11 @@ def start!(config = default_config)
         generator = build(config)
 
         RSpec.configure do |c|
-          c.before(:suite) { generator.load_map }
+          c.before(:suite) { generator.start! }
 
           c.around(:each) { |e| generator.refresh_for_case(e) }
 
-          c.after(:suite) { generator.dump_map }
+          c.after(:suite) { generator.finalize! }
         end
       end
 
@@ -25,40 +25,36 @@ def build(config)
       def default_config
         {
           execution_detector: ExecutionDetector.new(Dir.pwd),
+          map_class: StandardMap,
           map_storage: MapStorage::YAMLStorage.new('execution_map.yml')
         }
       end
     end
 
-
-    def initialize(execution_detector:, map_storage:)
+    def initialize(execution_detector:, map_class:, map_storage:)
       @execution_detector = execution_detector
       @map_storage = map_storage
+      @map = map_class.new(map_storage)
+    end
+
+    def start!
+      map_storage.clear!
     end
 
     def refresh_for_case(example)
       before = Coverage.peek_result
       example.run
       after = Coverage.peek_result
 
-      stash(CaseMap.new(example, execution_detector.detect(before, after)))
+      map.stash(CaseMap.new(example, execution_detector.detect(before, after)))
     end
 
-    def dump_map
-      map_storage.dump @stash
-    end
-
-    def load_map
-      @stash = map_storage.load
+    def finalize!
+      map.dump
     end
 
     private
 
-    attr_reader :execution_detector, :map_storage
-
-    def stash(case_map)
-      @stash ||= {}
-      @stash[case_map.case_uid] = case_map.coverage
-    end
+    attr_reader :execution_detector, :map, :map_storage
   end
 end

lib/crystalball/map_generator/simple_map.rb

@@ -0,0 +1,30 @@
+module Crystalball
+  class MapGenerator
+    class SimpleMap
+      def initialize(storage)
+        @storage = storage
+        @raw_map = {}
+      end
+
+      def load
+        self.raw_map = storage.load
+      end
+
+      def stash(case_map)
+        raw_map[case_map.case_uid] = case_map.coverage
+      end
+
+      def dump
+        storage.dump raw_map
+      end
+
+      def clear!
+        self.raw_map = {}
+      end
+
+      private
+
+      attr_accessor :raw_map, :storage
+    end
+  end
+end

lib/crystalball/map_generator/standard_map.rb

@@ -0,0 +1,22 @@
+module Crystalball
+  class MapGenerator
+    class StandardMap < SimpleMap
+      def initialize(storage, dump_threshold: 100)
+        super(storage)
+        @dump_threshold = dump_threshold
+      end
+
+      def stash(case_map)
+        super
+        if raw_map.size >= dump_threshold
+          dump
+          clear!
+        end
+      end
+
+      private
+
+      attr_reader :dump_threshold
+    end
+  end
+end

lib/crystalball/map_storage/yaml_storage.rb

@@ -9,12 +9,16 @@ def initialize(path)
         @path = path
       end
 
+      def clear!
+        File.delete(path) if File.exists?(path)
+      end
+
       def load
-        YAML.load(File.read(path)) if File.exists?(path)
+        YAML.safe_load(File.read(path)) if File.exists?(path)
       end
 
       def dump(map)
-        File.open(path, 'w') { |f| f.write YAML.dump(map) }
+        File.open(path, 'a') { |f| f.write YAML.dump(map) }
       end
     end
   end