Add coverband and custom tasks

Author: arielj

Gemfile

@@ -64,6 +64,7 @@ group :test do
   gem "capybara"
   gem "selenium-webdriver"
   gem "simplecov", require: false
+  gem "coverband"
 end
 
 gem "minitest", "~> 5.0"

Gemfile.lock

@@ -101,6 +101,9 @@ GEM
       xpath (~> 3.2)
     concurrent-ruby (1.3.6)
     connection_pool (3.0.2)
+    coverband (6.1.6)
+      base64
+      redis (>= 3.0)
     crass (1.0.6)
     cypress-on-rails (1.20.0)
       rack
@@ -267,6 +270,10 @@ GEM
       erb
       psych (>= 4.0.0)
       tsort
+    redis (5.4.1)
+      redis-client (>= 0.22.0)
+    redis-client (0.26.2)
+      connection_pool
     regexp_parser (2.11.3)
     reline (0.6.3)
       io-console (~> 0.5)
@@ -394,6 +401,7 @@ DEPENDENCIES
   brakeman
   bundler-audit
   capybara
+  coverband
   cypress-on-rails (~> 1.0)
   debug
   image_processing (~> 1.2)
@@ -443,6 +451,7 @@ CHECKSUMS
   capybara (3.40.0) sha256=42dba720578ea1ca65fd7a41d163dd368502c191804558f6e0f71b391054aeef
   concurrent-ruby (1.3.6) sha256=6b56837e1e7e5292f9864f34b69c5a2cbc75c0cf5338f1ce9903d10fa762d5ab
   connection_pool (3.0.2) sha256=33fff5ba71a12d2aa26cb72b1db8bba2a1a01823559fb01d29eb74c286e62e0a
+  coverband (6.1.6) sha256=8619896439d3394ca77fa839a67aecb456dc2e06072c88aefea80a9d24e28f09
   crass (1.0.6) sha256=dc516022a56e7b3b156099abc81b6d2b08ea1ed12676ac7a5657617f012bd45d
   cypress-on-rails (1.20.0) sha256=36e79d77d073f4b83d73a275b4908cb838e103adbad305882a683db0eb2ca7e4
   date (3.5.1) sha256=750d06384d7b9c15d562c76291407d89e368dda4d4fff957eb94962d325a0dc0
@@ -518,6 +527,8 @@ CHECKSUMS
   rainbow (3.1.1) sha256=039491aa3a89f42efa1d6dec2fc4e62ede96eb6acd95e52f1ad581182b79bc6a
   rake (13.3.1) sha256=8c9e89d09f66a26a01264e7e3480ec0607f0c497a861ef16063604b1b08eb19c
   rdoc (7.0.3) sha256=dfe3d0981d19b7bba71d9dbaeb57c9f4e3a7a4103162148a559c4fc687ea81f9
+  redis (5.4.1) sha256=b5e675b57ad22b15c9bcc765d5ac26f60b675408af916d31527af9bd5a81faae
+  redis-client (0.26.2) sha256=1336fb5a7202d398b719531853c184b7c9cbdcace1f00f8356062b9dfba6779b
   regexp_parser (2.11.3) sha256=ca13f381a173b7a93450e53459075c9b76a10433caadcb2f1180f2c741fc55a4
   reline (0.6.3) sha256=1198b04973565b36ec0f11542ab3f5cfeeec34823f4e54cebde90968092b1835
   rexml (3.4.4) sha256=19e0a2c3425dfbf2d4fc1189747bdb2f849b6c5e74180401b15734bc97b5d142

README.md

@@ -1,24 +1,19 @@
 # README
 
-This README would normally document whatever steps are necessary to get the
-application up and running.
+Run `rails db:migrate` to create the DB
 
-Things you may want to cover:
+Run `rails test` to run the Minitest test suite
 
-* Ruby version
+Check the coverage report: ~35%
 
-* System dependencies
+Run `RAILS_ENV=test rails coverband:coverage_server` to start the Coverband server in one terminal
 
-* Configuration
+Run `rails cypress:run` to run Cypress tests
 
-* Database creation
+Run `rails simplecov_json_report` to extract the code coverage from Coveband into a `cypress_coverage.json` (note that this command will show ~74% coverage, but it's not filtering files we don't want to count for the real coverage)
 
-* Database initialization
+Run `rails coverage:merge` to merge both Minitest and Cypress results into one
 
-* How to run the test suite
+Check the coverage report: ~52%
 
-* Services (job queues, cache servers, search engines, etc.)
-
-* Deployment instructions
-
-* ...
+NOTE: Use `RAILS_ENV=test rails coverband:clear` to clear Coverband's coverage if needed

lib/tasks/json_coverage.rake

@@ -0,0 +1,45 @@
+desc "static HTML formatted report of Coverband code coverage"
+task :simplecov_json_report do
+  require "coverband"
+  require "coverband/utils/html_formatter"
+  require "coverband/utils/result"
+  require "coverband/utils/file_list"
+  require "coverband/utils/source_file"
+  require "coverband/utils/lines_classifier"
+  require "coverband/utils/results"
+
+  require "simplecov"
+  require "simplecov_json_formatter"
+
+  `mkdir -p #{SimpleCov.coverage_path}`
+
+  # For a fully static HTML that can be copied to artifacts are part of CI
+  # we generate with inline assets
+  ENV["SIMPLECOV_INLINE_ASSETS"] = "true"
+
+  SimpleCovJSONFormatter::ResultExporter.send(:remove_const, "FILENAME")
+  SimpleCovJSONFormatter::ResultExporter::FILENAME = "cypress_coverage.json"
+
+  coverband_reports = Coverband::Reporters::Base.report(Coverband.configuration.store)
+  Coverband::Reporters::Base.fix_reports(coverband_reports)
+  result = Coverband::Utils::Results.new(coverband_reports)
+  SimpleCov::Formatter::JSONFormatter.new.format(result)
+
+  # fix json structure so it can be merged with coverage:merge
+  generated_json_file = File.join(SimpleCov.coverage_path, SimpleCovJSONFormatter::ResultExporter::FILENAME)
+  content = { "Cypress" => JSON.parse(File.read(generated_json_file)) }
+  File.write(generated_json_file, content.to_json)
+end
+
+namespace :coverage do
+  desc "Merge Minitest's and Cypress' code coverage json files into one"
+  task :merge do
+    require "simplecov"
+
+    # change this if you use different json result names
+    coverage_files = Dir["#{SimpleCov.coverage_path}/.resultset.json"] + Dir["#{SimpleCov.coverage_path}/cypress_coverage.json"]
+
+    # make sure to use the `rails` profile to not add noise with files we won't test
+    SimpleCov.collate coverage_files, "rails"
+  end
+end

test/test_helper.rb

@@ -1,6 +1,7 @@
 ENV["RAILS_ENV"] ||= "test"
+
 require "simplecov"
-SimpleCov.start
+SimpleCov.start "rails"
 
 require_relative "../config/environment"
 require "rails/test_help"