Improve Dependency Processing (#26)

Cache the filtered files to speed up changed dependencies per example.
Also, do not compute diff when last example and current example coverage
is same for a given file.

Author: avmnu-sng

lib/rspec_tracer.rb

@@ -250,7 +250,7 @@ def write_coverage_report(file_name)
         }
       }
 
-      File.write(file_name, JSON.generate(report))
+      File.write(file_name, JSON.pretty_generate(report))
     end
 
     def print_coverage_stats(file_name, elpased)

lib/rspec_tracer/coverage_reporter.rb

@@ -29,11 +29,15 @@ def record_coverage
 
     def compute_diff(example_id)
       peek_coverage.each_pair do |file_path, current_stats|
-        if @coverage.key?(file_path)
-          existing_file_diff_coverage(example_id, file_path, current_stats)
-        else
+        unless @coverage.key?(file_path)
           missing_file_diff_coverage(example_id, file_path, current_stats)
+
+          next
         end
+
+        next if current_stats == @coverage[file_path]
+
+        existing_file_diff_coverage(example_id, file_path, current_stats)
       end
     end
 

lib/rspec_tracer/reporter.rb

@@ -229,56 +229,56 @@ def format_reverse_dependency_report
     def write_all_examples_report
       file_name = File.join(@cache_dir, 'all_examples.json')
 
-      File.write(file_name, JSON.generate(@all_examples))
+      File.write(file_name, JSON.pretty_generate(@all_examples))
     end
 
     def write_flaky_examples_report
       file_name = File.join(@cache_dir, 'flaky_examples.json')
 
-      File.write(file_name, JSON.generate(@flaky_examples.to_a))
+      File.write(file_name, JSON.pretty_generate(@flaky_examples.to_a))
     end
 
     def write_failed_examples_report
       file_name = File.join(@cache_dir, 'failed_examples.json')
 
-      File.write(file_name, JSON.generate(@failed_examples.to_a))
+      File.write(file_name, JSON.pretty_generate(@failed_examples.to_a))
     end
 
     def write_pending_examples_report
       file_name = File.join(@cache_dir, 'pending_examples.json')
 
-      File.write(file_name, JSON.generate(@pending_examples.to_a))
+      File.write(file_name, JSON.pretty_generate(@pending_examples.to_a))
     end
 
     def write_all_files_report
       file_name = File.join(@cache_dir, 'all_files.json')
 
-      File.write(file_name, JSON.generate(@all_files))
+      File.write(file_name, JSON.pretty_generate(@all_files))
     end
 
     def write_dependency_report
       file_name = File.join(@cache_dir, 'dependency.json')
 
-      File.write(file_name, JSON.generate(@dependency))
+      File.write(file_name, JSON.pretty_generate(@dependency))
     end
 
     def write_reverse_dependency_report
       file_name = File.join(@cache_dir, 'reverse_dependency.json')
 
-      File.write(file_name, JSON.generate(@reverse_dependency))
+      File.write(file_name, JSON.pretty_generate(@reverse_dependency))
     end
 
     def write_examples_coverage_report
       file_name = File.join(@cache_dir, 'examples_coverage.json')
 
-      File.write(file_name, JSON.generate(@examples_coverage))
+      File.write(file_name, JSON.pretty_generate(@examples_coverage))
     end
 
     def write_last_run_report
       file_name = File.join(RSpecTracer.cache_path, 'last_run.json')
       last_run_data = @last_run.merge(run_id: @run_id, timestamp: Time.now.utc)
 
-      File.write(file_name, JSON.generate(last_run_data))
+      File.write(file_name, JSON.pretty_generate(last_run_data))
     end
   end
 end

lib/rspec_tracer/runner.rb

@@ -90,16 +90,15 @@ def generate_missed_coverage
     # rubocop:enable Metrics/AbcSize
 
     def register_dependency(examples_coverage)
+      filtered_files = Set.new
+
       examples_coverage.each_pair do |example_id, example_coverage|
         register_example_files_dependency(example_id)
 
         example_coverage.each_key do |file_path|
-          source_file = RSpecTracer::SourceFile.from_path(file_path)
-
-          next if RSpecTracer.filters.any? { |filter| filter.match?(source_file) }
+          next if filtered_files.include?(file_path)
 
-          @reporter.register_source_file(source_file)
-          @reporter.register_dependency(example_id, source_file[:file_name])
+          filtered_files << file_path unless register_file_dependency(example_id, file_path)
         end
       end
 
@@ -260,6 +259,17 @@ def register_example_file_dependency(example_id, file_name)
       @reporter.register_dependency(example_id, file_name)
     end
 
+    def register_file_dependency(example_id, file_path)
+      source_file = RSpecTracer::SourceFile.from_path(file_path)
+
+      return false if RSpecTracer.filters.any? { |filter| filter.match?(source_file) }
+
+      @reporter.register_source_file(source_file)
+      @reporter.register_dependency(example_id, source_file[:file_name])
+
+      true
+    end
+
     def generate_examples_status_report
       starting = Process.clock_gettime(Process::CLOCK_MONOTONIC)