Add support for ruby 3.1.0, compose for coverage

Dockerfile

@@ -0,0 +1,15 @@
+ARG BASE_IMAGE=ruby:2.7
+FROM ${BASE_IMAGE}
+
+WORKDIR /app
+
+COPY gems.rb *.gemspec ./
+COPY lib/yaml/safe_load_stream/version.rb ./lib/yaml/safe_load_stream/
+
+RUN gem install bundler:2.3.5
+RUN bundle install
+RUN bundle update --bundler
+
+COPY . .
+
+ENTRYPOINT ["bundle", "exec"]

docker-compose.yaml

@@ -0,0 +1,36 @@
+services:
+  rspec-2.6:
+    build:
+      context: .
+      args:
+        BASE_IMAGE: ruby:2.6
+    volumes:
+      - .:/app
+    entrypoint: bundle exec rspec
+
+  rspec-2.7:
+    build:
+      context: .
+      args:
+        BASE_IMAGE: ruby:2.7
+    volumes:
+      - .:/app
+    entrypoint: bundle exec rspec
+
+  rspec-3.0:
+    build:
+      context: .
+      args:
+        BASE_IMAGE: ruby:3.0
+    volumes:
+      - .:/app
+    entrypoint: bundle exec rspec
+
+  rspec-3.1:
+    build:
+      context: .
+      args:
+        BASE_IMAGE: ruby:3.1
+    volumes:
+      - .:/app
+    entrypoint: bundle exec rspec

lib/yaml/safe_load_stream.rb

@@ -13,7 +13,7 @@ module YAMLSafeLoadStream
   # @return [Array] when a block is not given, returns an Array of documents
   module_function def safe_load_stream(yaml, filename = nil)
     result = []
-    ::YAML.parse_stream(yaml, filename) do |stream|
+    ::YAML.parse_stream(yaml, filename: filename) do |stream|
       raise_if_tags(stream, filename)
       result << if block_given?
                   yield(stream.to_ruby)
@@ -38,7 +38,11 @@ module YAMLSafeLoadStream
                        "in document #{doc_num}"
                      end
           message += " in file #{filename}" if filename
-          raise Psych::DisallowedClass, message
+          if RUBY_VERSION < "3.1.0"
+            raise Psych::DisallowedClass, message
+          else
+            raise Psych::DisallowedClass.new(:load, message)
+          end
         end
       end
     end