Fixed nullable specs after the usage of the new Java StringSetting instead of Ruby one

Author: andsel

logstash-core/lib/logstash/settings.rb

@@ -827,6 +827,8 @@ def validate(value)
       end
     end
 
+    java_import org.logstash.settings.NullableSetting
+
     # @see Setting#nullable
     # @api internal
     class Nullable < SimpleDelegator

logstash-core/lib/logstash/util/settings_helper.rb

@@ -33,8 +33,8 @@ module LogStash::Util::SettingsHelper
   # The `path.settings` and `path.logs` can not be defined in "logstash/environment" since the `Environment::LOGSTASH_HOME` doesn't
   # exist unless launched via "bootstrap/environment"
   def self.pre_process
-    LogStash::SETTINGS.register(LogStash::Setting::String.new("path.settings", ::File.join(LogStash::Environment::LOGSTASH_HOME, "config")))
-    LogStash::SETTINGS.register(LogStash::Setting::String.new("path.logs", ::File.join(LogStash::Environment::LOGSTASH_HOME, "logs")))
+    LogStash::SETTINGS.register(LogStash::Setting::StringSetting.new("path.settings", ::File.join(LogStash::Environment::LOGSTASH_HOME, "config")))
+    LogStash::SETTINGS.register(LogStash::Setting::StringSetting.new("path.logs", ::File.join(LogStash::Environment::LOGSTASH_HOME, "logs")))
   end
 
   # Ensure that any settings are re-calculated after loading yaml

logstash-core/spec/logstash/settings/nullable_spec.rb

@@ -20,13 +20,13 @@
 
 describe LogStash::Setting::Nullable do
   let(:setting_name) { "this.that" }
-  let(:normal_setting) { LogStash::Setting::String.new(setting_name, nil, false, possible_strings) }
+  let(:normal_setting) { LogStash::Setting::StringSetting.new(setting_name, nil, false, possible_strings) }
   let(:possible_strings) { [] } # empty means any string passes
 
   subject(:nullable_setting) { normal_setting.nullable }
 
   it 'is a kind of Nullable' do
-    expect(nullable_setting).to be_a_kind_of(described_class)
+    expect(nullable_setting).to be_a_kind_of(LogStash::Setting::NullableSetting)
   end
 
   it "retains the wrapped setting's name" do
@@ -56,14 +56,14 @@
     context 'to an invalid wrong-type value' do
       let(:candidate_value) { 127 } # wrong type, expects String
       it 'is an invalid setting' do
-        expect { nullable_setting.validate_value }.to raise_error(ArgumentError, a_string_including("Setting \"#{setting_name}\" must be a "))
+        expect { nullable_setting.validate_value }.to raise_error(java.lang.ClassCastException, a_string_including("class java.lang.Long cannot be cast to class java.lang.String"))
       end
     end
     context 'to an invalid value not in the allow-list' do
       let(:possible_strings) { %w(this that)}
       let(:candidate_value) { "another" } # wrong type, expects String
       it 'is an invalid setting' do
-        expect { nullable_setting.validate_value }.to raise_error(ArgumentError, a_string_including("Invalid value"))
+        expect { nullable_setting.validate_value }.to raise_error(java.lang.IllegalArgumentException, a_string_including("Invalid value"))
       end
     end
     context 'to a valid value' do