Fix recursive prune_bundler

Resolve #2319

History.md

@@ -2,6 +2,7 @@
 * Bugfixes
   * Resolve issue with threadpool waiting counter decrement when thread is killed
   * Constrain rake-compiler version to 0.9.4 to fix `ClassNotFound` exception when using MiniSSL with Java8.
+  * Fix recursive `prune_bundler` (#2319).
 
 ## 5.0.0
 

lib/puma/launcher.rb

@@ -288,6 +288,7 @@ module Puma
     end
 
     def prune_bundler
+      return if ENV['PUMA_BUNDLER_PRUNED']
       return unless defined?(Bundler)
       require_rubygems_min_version!(Gem::Version.new("2.2"), "prune_bundler")
       unless puma_wild_location

test/config/prune_bundler_with_multiple_workers.rb

@@ -0,0 +1,14 @@
+require 'bundler/setup'
+Bundler.setup
+
+prune_bundler true
+
+workers 2
+
+app do |env|
+  [200, {}, ["embedded app"]]
+end
+
+lowlevel_error_handler do |err|
+  [200, {}, ["error page"]]
+end

test/test_integration_cluster.rb

@@ -198,6 +198,30 @@ RUBY
     assert output, "Friendly fork didn't run"
   end
 
+  def test_prune_bundler_with_multiple_workers
+    cli_server "", config: <<RUBY
+require 'bundler/setup'
+Bundler.setup
+
+prune_bundler true
+
+workers 2
+
+app do |env|
+  [200, {}, ["embedded app"]]
+end
+
+lowlevel_error_handler do |err|
+  [200, {}, ["error page"]]
+end
+RUBY
+
+    connection = connect
+    reply = read_body(connection)
+
+    assert reply, "embedded app"
+  end
+
   private
 
   def worker_timeout(timeout, iterations, config)

test/test_integration_pumactl.rb

@@ -90,6 +90,26 @@ class TestIntegrationPumactl < TestIntegration
     @server = nil
   end
 
+  def test_prune_bundler_with_multiple_workers
+    skip NO_FORK_MSG unless HAS_FORK
+
+    cli_server "-q -C test/config/prune_bundler_with_multiple_workers.rb --control-url unix://#{@control_path} --control-token #{TOKEN} -S #{@state_path}", unix: true
+
+    s = UNIXSocket.new @bind_path
+    @ios_to_close << s
+    s << "GET / HTTP/1.0\r\n\r\n"
+
+    body = s.read
+
+    assert_match "200 OK", body
+    assert_match "embedded app", body
+
+    cli_pumactl "stop", unix: true
+
+    _, status = Process.wait2(@pid)
+    @server = nil
+  end
+
   def test_kill_unknown
     skip_on :jruby