Fix compatibility with Ractors

CHANGELOG.md

@@ -1,5 +1,7 @@
 # Unreleased
 
+- Make `RedisClient::RESP3::DUMP_TYPES` immutable to allow Ractor compatibility and add basic tests for usage with Ractors.
+
 # 0.19.1
 
 - Fixed a bug in `hiredis-client` that could cause a crash if interrupted by `Timeout.timeout` or other `Thread#raise` based mecanism.

lib/redis_client/ruby_connection/resp3.rb

@@ -10,12 +10,12 @@ module RESP3
 
     EOL = "\r\n".b.freeze
     EOL_SIZE = EOL.bytesize
-    DUMP_TYPES = { # rubocop:disable Style/MutableConstant
+    DUMP_TYPES = {
       String => :dump_string,
       Symbol => :dump_symbol,
       Integer => :dump_numeric,
       Float => :dump_numeric,
-    }
+    }.freeze
     PARSER_TYPES = {
       '#' => :parse_boolean,
       '$' => :parse_blob,
@@ -57,7 +57,7 @@ def new_buffer
     def dump_any(object, buffer)
       method = DUMP_TYPES.fetch(object.class) do |unexpected_class|
         if superclass = DUMP_TYPES.keys.find { |t| t > unexpected_class }
-          DUMP_TYPES[unexpected_class] = DUMP_TYPES[superclass]
+          DUMP_TYPES[superclass]
         else
           raise TypeError, "Unsupported command argument type: #{unexpected_class}"
         end

test/redis_client/ractor_test.rb

@@ -0,0 +1,44 @@
+# frozen_string_literal: true
+
+require "test_helper"
+
+class RactorTest < Minitest::Test
+  def setup
+    skip("Ractors are not supported on this Ruby version") unless defined?(::Ractor)
+    skip("Hiredis is not Ractor safe") if RedisClient.default_driver.name == "RedisClient::HiredisConnection"
+    begin
+      Ractor.new { RedisClient.default_driver.name }.take
+    rescue Ractor::RemoteError
+      skip("Ractor implementation is too limited (MRI 3.0?)")
+    end
+  end
+
+  def test_get_and_set_within_ractor
+    ractor = Ractor.new do
+      within_ractor_redis = ClientTestHelper.new_client
+      within_ractor_redis.call("SET", "foo", "bar")
+      within_ractor_redis.call("GET", "foo")
+    end
+
+    assert_equal("bar", ractor.take)
+  end
+
+  def test_multiple_ractors
+    ractor1 = Ractor.new do
+      within_ractor_redis = ClientTestHelper.new_client
+      within_ractor_redis.call("SET", "foo", "bar")
+      within_ractor_redis.call("GET", "foo")
+    end
+
+    ractor1.take # We do this to ensure that the SET has been processed
+
+    ractor2 = Ractor.new do
+      key = Ractor.receive
+      within_ractor_redis = ClientTestHelper.new_client
+      within_ractor_redis.call("GET", key)
+    end
+    ractor2.send("foo")
+
+    assert_equal("bar", ractor2.take)
+  end
+end

test/support/client_test_helper.rb

@@ -50,6 +50,28 @@ def travel(seconds, &block)
     Process.stub(:clock_gettime, now, &block)
   end
 
+  def simulate_network_errors(client, failures)
+    client.close
+    client.instance_variable_set(:@raw_connection, nil)
+
+    original_config = client.config
+    flaky_driver = Class.new(original_config.driver)
+    flaky_driver.include(FlakyDriver)
+    flaky_driver.failures = failures
+    flaky_config = original_config.dup
+    flaky_config.instance_variable_set(:@driver, flaky_driver)
+    begin
+      client.instance_variable_set(:@config, flaky_config)
+      yield
+    ensure
+      client.instance_variable_set(:@config, original_config)
+      client.close
+      client.instance_variable_set(:@raw_connection, nil)
+    end
+  end
+
+  module_function
+
   def tcp_config
     {
       host: Servers::HOST,
@@ -82,24 +104,4 @@ def unix_config
   def new_client(**overrides)
     RedisClient.new(**tcp_config.merge(overrides))
   end
-
-  def simulate_network_errors(client, failures)
-    client.close
-    client.instance_variable_set(:@raw_connection, nil)
-
-    original_config = client.config
-    flaky_driver = Class.new(original_config.driver)
-    flaky_driver.include(FlakyDriver)
-    flaky_driver.failures = failures
-    flaky_config = original_config.dup
-    flaky_config.instance_variable_set(:@driver, flaky_driver)
-    begin
-      client.instance_variable_set(:@config, flaky_config)
-      yield
-    ensure
-      client.instance_variable_set(:@config, original_config)
-      client.close
-      client.instance_variable_set(:@raw_connection, nil)
-    end
-  end
 end

test/support/raise_warnings.rb

@@ -3,7 +3,10 @@
 $VERBOSE = true
 module RaiseWarnings
   def warn(message, *)
+    return if message.include?('Ractor is experimental')
+
     super
+
     raise message
   end
   ruby2_keywords :warn if respond_to?(:ruby2_keywords, true)