Register at_exit for all coverband processes

lib/coverband.rb

@@ -5,6 +5,7 @@
 require 'redis'
 
 require 'coverband/version'
+require 'coverband/at_exit'
 require 'coverband/configuration'
 require 'coverband/adapters/base'
 require 'coverband/adapters/redis_store'
@@ -52,6 +53,7 @@ def self.configuration
 
   def self.start
     Coverband::Collectors::Coverage.instance
+    AtExit.register
     Background.start if configuration.background_reporting_enabled && !RackServerCheck.running?
   end
 

lib/coverband/at_exit.rb

@@ -0,0 +1,20 @@
+# frozen_string_literal: true
+
+module Coverband
+  class AtExit
+    @semaphore = Mutex.new
+
+    def self.register
+      return if @at_exit_registered
+      @semaphore.synchronize do
+        return if @at_exit_registered
+        @at_exit_registered = true
+        at_exit do
+          ::Coverband::Background.stop
+          Coverband::Collectors::Coverage.instance.report_coverage(true)
+          Coverband.configuration.logger&.debug('Coverband: Reported coverage before exit')
+        end
+      end
+    end
+  end
+end

lib/coverband/integrations/background.rb

@@ -29,11 +29,6 @@ def self.start
           end
         end
       end
-      at_exit do
-        stop
-        Coverband::Collectors::Coverage.instance.report_coverage(true)
-        logger&.debug('Coverband: Reported coverage before exit')
-      end
     end
   end
 end

lib/coverband/integrations/middleware.rb

@@ -9,10 +9,11 @@ def initialize(app)
     def call(env)
       @app.call(env)
     ensure
+      AtExit.register
       if Coverband.configuration.background_reporting_enabled
-        Coverband::Background.start
+        Background.start
       else
-        Coverband::Collectors::Coverage.instance.report_coverage
+        Collectors::Coverage.instance.report_coverage
       end
     end
   end

test/unit/at_exit_test.rb

@@ -0,0 +1,13 @@
+# frozen_string_literal: true
+
+require File.expand_path('../test_helper', File.dirname(__FILE__))
+
+class AtExitTest < Minitest::Test
+  test 'only registers once' do
+    Coverband::AtExit.instance_eval { @at_exit_registered = nil }
+    Coverband::AtExit.expects(:at_exit).yields.once.returns(true)
+    2.times { Coverband::AtExit.register }
+  end
+end
+
+

test/unit/background_test.rb

@@ -22,7 +22,6 @@ def test_start
     Thread.expects(:new).yields.returns(ThreadDouble.new)
     Coverband::Background.expects(:loop).yields
     Coverband::Background.expects(:sleep).with(30)
-    Coverband::Background.expects(:at_exit).returns(false)
     Coverband::Collectors::Coverage.instance.expects(:report_coverage).once
     2.times { Coverband::Background.start }
   end