test: start simplecov before library code is loaded

Author: zvkemp

.github/actions/test_gem/action.yml

@@ -19,6 +19,16 @@ inputs:
     required: false
     type: boolean
     default: false
+  coverage:
+    description: Enforce SimpleCov
+    required: false
+    type: boolean
+    default: false
+  minimum_coverage:
+    description: Minimum test coverage
+    required: false
+    type: string
+    default: 85
   build:
     description: Build gem
     required: false
@@ -153,6 +163,13 @@ runs:
         bundle exec rake rubocop
       working-directory: "${{ steps.setup.outputs.gem_dir }}"
 
+    - name: Coverage
+      shell: bash
+      if: "${{ inputs.coverage == 'true' }}"
+      # This starts a new simplecov run which tracks nothing of its own,
+      # but merges with the existing coverage reports generated during testing.
+      run: "bundle exec ruby -rsimplecov -e 'SimpleCov.minimum_coverage(${{ inputs.minimum_coverage }})'"
+
     - name: Build Gem
       shell: bash
       if: "${{ inputs.build == 'true' }}"

.github/workflows/ci-instrumentation-with-services.yml

@@ -46,6 +46,7 @@ jobs:
           ruby: "3.1"
           yard: true
           rubocop: true
+          coverage: true
           build: true
       - name: "Test JRuby"
         uses: ./.github/actions/test_gem
@@ -92,6 +93,7 @@ jobs:
           ruby: "3.1"
           yard: true
           rubocop: true
+          coverage: true
           build: true
     services:
       mysql:
@@ -129,6 +131,7 @@ jobs:
           ruby: "3.1"
           yard: true
           rubocop: true
+          coverage: true
           build: true
     services:
       zookeeper:
@@ -182,6 +185,7 @@ jobs:
           ruby: "3.1"
           yard: true
           rubocop: true
+          coverage: true
           build: true
     services:
       redis:
@@ -226,6 +230,7 @@ jobs:
           ruby: "3.1"
           yard: true
           rubocop: true
+          coverage: true
           build: true
     services:
       postgres:
@@ -267,6 +272,7 @@ jobs:
           ruby: "3.1"
           yard: true
           rubocop: true
+          coverage: true
           build: true
     services:
       rabbitmq:

.github/workflows/ci-instrumentation.yml

@@ -72,10 +72,11 @@ jobs:
       - name: "Test Ruby 3.1"
         uses: ./.github/actions/test_gem
         with:
-          gem:  "opentelemetry-instrumentation-${{ matrix.gem }}"
+          gem: "opentelemetry-instrumentation-${{ matrix.gem }}"
           ruby: "3.1"
           yard: true
           rubocop: true
+          coverage: true
           build: true
       - name: "JRuby Filter"
         id: jruby_skip

.simplecov

@@ -0,0 +1,14 @@
+require 'digest'
+
+digest = Digest::MD5.new
+digest.update('test')
+digest.update(ENV.fetch('BUNDLE_GEMFILE', 'gemfile')) if ENV['APPRAISAL_INITIALIZED']
+
+ENV['ENABLE_COVERAGE'] ||= '1'
+
+if ENV['ENABLE_COVERAGE'].to_i.positive?
+  SimpleCov.command_name(digest.hexdigest)
+  SimpleCov.start do
+    add_filter %r{^/test/}
+  end
+end

helpers/mysql/test/test_helper.rb

@@ -4,6 +4,7 @@
 #
 # SPDX-License-Identifier: Apache-2.0
 
+require 'simplecov'
 require 'bundler/setup'
 Bundler.require(:default, :development, :test)
 

instrumentation/action_mailer/test/test_helper.rb

@@ -4,6 +4,7 @@
 #
 # SPDX-License-Identifier: Apache-2.0
 
+require 'simplecov'
 require 'logger'
 require 'bundler/setup'
 Bundler.require(:default, :development, :test)

instrumentation/action_pack/test/test_helper.rb

@@ -4,6 +4,7 @@
 #
 # SPDX-License-Identifier: Apache-2.0
 
+require 'simplecov'
 require 'logger'
 require 'bundler/setup'
 Bundler.require(:default, :development, :test)

instrumentation/action_view/test/test_helper.rb

@@ -4,6 +4,7 @@
 #
 # SPDX-License-Identifier: Apache-2.0
 
+require 'simplecov'
 require 'logger'
 require 'bundler/setup'
 Bundler.require(:default, :development, :test)

instrumentation/active_job/test/test_helper.rb

@@ -5,6 +5,7 @@
 # SPDX-License-Identifier: Apache-2.0
 ENV['OTEL_LOG_LEVEL'] ||= 'fatal'
 
+require 'simplecov'
 require 'bundler/setup'
 Bundler.require(:default, :development, :test)
 

instrumentation/active_model_serializers/test/test_helper.rb

@@ -4,6 +4,7 @@
 #
 # SPDX-License-Identifier: Apache-2.0
 
+require 'simplecov'
 require 'bundler/setup'
 Bundler.require(:default, :development, :test)