Fixes the bug that wouldn't allow no_token be set to true (#1803)

* Fix crash when no_token is set

* Use a more meaningful name instead of an empty string

* Adds a test to ensure `{ no_token: true }` works

* Adds an explanation for the usage of a String

Just to justify the use of a String instead of a Symbol.

* Removes thread that would start the server

This removes the part of the test that would start the server. The
reason why the thread was being created originally in the PR was to
ensure that the server was booting even with `{ no_token: true }`.

I believe we don't need to test the full server boot but just ensure
that we won't pass a Symbol to OptionParser. In particular the test
ensures that the token will be set to `'none'` when `no_token: true`.

There're already other tests testing that the server boots.

lib/puma/dsl.rb

@@ -105,7 +105,12 @@ module Puma
       end
 
       if opts[:no_token]
-        auth_token = :none
+        # We need to use 'none' rather than :none because this value will be
+        # passed on to an instance of OptionParser, which doesn't support
+        # symbols as option values.
+        #
+        # See: https://github.com/puma/puma/issues/1193#issuecomment-305995488
+        auth_token = 'none'
       else
         auth_token = opts[:auth_token]
         auth_token ||= Configuration.random_token

lib/puma/runner.rb

@@ -55,7 +55,7 @@ module Puma
       app = Puma::App::Status.new @launcher
 
       if token = @options[:control_auth_token]
-        app.auth_token = token unless token.empty? or token == :none
+        app.auth_token = token unless token.empty? || token == 'none'
       end
 
       control = Puma::Server.new app, @launcher.events

test/config/control_no_token.rb

@@ -0,0 +1,5 @@
+activate_control_app 'unix:///tmp/pumactl.sock', { no_token: true }
+
+app do |env|
+  [200, {}, ["embedded app"]]
+end

test/test_pumactl.rb

@@ -29,6 +29,16 @@ class TestPumaControlCli < Minitest::Test
     assert_equal "t3-pid", control_cli.instance_variable_get("@pidfile")
   end
 
+  def test_control_no_token
+    opts = [
+      "--config-file", "test/config/control_no_token.rb",
+      "start"
+    ]
+
+    control_cli = Puma::ControlCLI.new opts, @ready, @ready
+    assert_equal 'none', control_cli.instance_variable_get("@control_auth_token")
+  end
+
   def test_control_url
     host = "127.0.0.1"
     port = find_open_port