update URLMap Regexp usage for Ruby v3.3 (#3165)

* update URLMap Regexp usage for Ruby v3.3

Ruby v3.3.0-preview1 doesn't support passing 3 arguments to
`Regexp.new`, so update `URLMap` to use a 2 argument version instead.

* Add unit test for PR 3165

With a `Gemfile` that excludes `rack`, have Puma use its own `URLMap`
class to handle the mapping of the route defined in `config.ru`. Without
the fix provided by PR 3165, this new test will time out.

* test_url_map.rb - run single

* test/url_map_test/config.ru - check whether Rack::URLMap is defined

Just in case...

---------

Co-authored-by: MSP-Greg <Greg.mpls@gmail.com>

lib/puma/rack/urlmap.rb

@@ -34,7 +34,7 @@ def remap(map)
         end
 
         location = location.chomp('/')
-        match = Regexp.new("^#{Regexp.quote(location).gsub('/', '/+')}(.*)", nil, 'n')
+        match = Regexp.new("^#{Regexp.quote(location).gsub('/', '/+')}(.*)", Regexp::NOENCODING)
 
         [host, location, match, app]
       }.sort_by do |(host, location, _, _)|

test/test_url_map.rb

@@ -0,0 +1,24 @@
+require_relative "helper"
+require_relative "helpers/integration"
+
+class TestURLMap < TestIntegration
+
+  def teardown
+    return if skipped?
+    super
+  end
+
+  # make sure the mapping defined in url_map_test/config.ru works
+  def test_basic_url_mapping
+    skip_if :jruby
+    env = { "BUNDLE_GEMFILE" => "#{__dir__}/url_map_test/Gemfile" }
+    Dir.chdir("#{__dir__}/url_map_test") do
+      cli_server set_pumactl_args, env: env
+    end
+    connection = connect("/ok")
+    # Puma 6.2.2 and below will time out here with Ruby v3.3
+    # see https://github.com/puma/puma/pull/3165
+    body = read_body(connection, 1)
+    assert_equal("OK", body)
+  end
+end

test/url_map_test/Gemfile

@@ -0,0 +1 @@
+gem 'puma', path: '../..'

test/url_map_test/config.ru

@@ -0,0 +1,9 @@
+map "/ok" do
+  run ->(env) {
+    if Object.const_defined?(:Rack) && ::Rack.const_defined?(:URLMap)
+      [200, {}, ["::Rack::URLMap is loaded"]]
+    else
+      [200, {}, ["OK"]]
+    end
+  }
+end