Add some blank validator tests

spec/graphql/schema/validator/allow_blank_validator_spec.rb

@@ -20,9 +20,20 @@
   end
 
   it "can be used standalone" do
-    schema = build_schema(String, { allow_blank: false })
+    schema = build_schema(String, { allow_blank: false, allow_null: false })
     result = schema.execute("query($str: String) { validated(value: $str) }", variables: { str: ValidatorHelpers::BlankString.new })
     assert_nil result["data"]["validated"]
     assert_equal ["value can't be blank"], result["errors"].map { |e| e["message"] }
+
+    result = schema.execute("query($str: String) { validated: validatedArgResolver(input: $str) }", variables: { str: "abc" })
+    assert_equal "ABC", result["data"]["validated"]
+
+    result = schema.execute("query($str: String) { validated: validatedArgResolver(input: $str) }", variables: { str: ValidatorHelpers::BlankString.new })
+    assert_nil result.fetch("data")
+    assert_equal ["input can't be blank"], result["errors"].map { |e| e["message"] }
+
+    # The validator doesn't run if the argument isn't present:
+    result = schema.execute("query($str: String) { validated: validatedArgResolver(input: $str) }", variables: {  })
+    assert_equal "NO_INPUT", result["data"]["validated"]
   end
 end

spec/graphql/schema/validator/validator_helpers.rb

@@ -40,6 +40,15 @@ def resolve(a: 0, b: 0, c: 0)
       end
     end
 
+    validated_arg_resolver = Class.new(GraphQL::Schema::Resolver) do
+      graphql_name "ValidatedArgResolver"
+      argument :input, arg_type, required: false, validates: validates_config
+      type(String, null: false)
+      def resolve(input: :NO_INPUT)
+        input.to_s.upcase
+      end
+    end
+
     query_type = Class.new(GraphQL::Schema::Object) do
       graphql_name "Query"
       field :validated, arg_type do
@@ -69,7 +78,7 @@ def validated_input(input:)
       end
 
       field :validated_resolver, resolver: validated_resolver
-
+      field :validated_arg_resolver, resolver: validated_arg_resolver
       field :list, [self], null: false
 
       def list