fix: union definition re-using (#760)

Author: ms-jpq

lib/openai/helpers/structured_output/union_of.rb

@@ -36,7 +36,17 @@ def to_json_schema_inner(state:)
               mergeable_keys.each_key { mergeable_keys[_1] += 1 if schema.keys == _1 }
             end
             mergeable = mergeable_keys.any? { _1.last == schemas.length }
-            mergeable ? OpenAI::Internal::Util.deep_merge(*schemas, concat: true) : {anyOf: schemas}
+            if mergeable
+              OpenAI::Internal::Util.deep_merge(*schemas, concat: true)
+            else
+              {
+                anyOf: schemas.each do
+                  if _1.key?(:$ref)
+                    _1.update(OpenAI::Helpers::StructuredOutput::JsonSchemaConverter::NO_REF => true)
+                  end
+                end
+              }
+            end
           end
         end
 

test/openai/helpers/structured_output_test.rb

@@ -37,6 +37,7 @@ class M3 < OpenAI::Helpers::StructuredOutput::BaseModel
 
   U1 = OpenAI::Helpers::StructuredOutput::UnionOf[Integer, A1]
   U2 = OpenAI::Helpers::StructuredOutput::UnionOf[:type, m2: M2, m3: M3]
+  U3 = OpenAI::Helpers::StructuredOutput::UnionOf[A1, A1]
 
   def test_coerce
     cases = {
@@ -159,6 +160,12 @@ class M10 < OpenAI::Helpers::StructuredOutput::BaseModel
     required :b, -> { M9 }
   end
 
+  class M11 < OpenAI::Helpers::StructuredOutput::BaseModel
+    required :a, U3
+    required :b, A1
+    required :c, A1
+  end
+
   def test_definition_reusing
     cases = {
       M6 => {
@@ -296,6 +303,27 @@ def test_definition_reusing
                 }
           },
         :$ref => "#/$defs/"
+      },
+      U3 => {
+        anyOf: [
+          {type: "array", items: {type: "string"}},
+          {type: "array", items: {type: "string"}}
+        ]
+      },
+      M11 => {
+        type: "object",
+        properties: {
+          a: {
+            anyOf: [
+              {type: "array", items: {type: "string"}},
+              {type: "array", items: {type: "string"}}
+            ]
+          },
+          b: {type: "array", items: {type: "string"}},
+          c: {type: "array", items: {type: "string"}}
+        },
+        required: %w[a b c],
+        additionalProperties: false
       }
     }
 
@@ -307,23 +335,23 @@ def test_definition_reusing
     end
   end
 
-  class M11 < OpenAI::Helpers::StructuredOutput::BaseModel
+  class M12 < OpenAI::Helpers::StructuredOutput::BaseModel
     required :a, OpenAI::Helpers::StructuredOutput::ParsedJson
   end
 
   def test_parsed_json
     assert_pattern do
-      M11.new(a: {dog: "woof"}) => {a: {dog: "woof"}}
+      M12.new(a: {dog: "woof"}) => {a: {dog: "woof"}}
     end
 
     err = JSON::ParserError.new("unexpected token at 'invalid json'")
 
-    m1 = M11.new(a: err)
+    m1 = M12.new(a: err)
     assert_raises(OpenAI::Errors::ConversionError) do
       m1.a
     end
 
-    m2 = OpenAI::Internal::Type::Converter.coerce(M11, {a: err})
+    m2 = OpenAI::Internal::Type::Converter.coerce(M12, {a: err})
     assert_raises(OpenAI::Errors::ConversionError) do
       m2.a
     end