From 159f747a5577af7955b2d9bf743909913db64bc1 Mon Sep 17 00:00:00 2001
From: Matvey <38750524+mtovts@users.noreply.github.com>
Date: Fri, 13 Aug 2021 11:51:40 +0300
Subject: [PATCH 01/11] Add the creation of empty classes. It allows to
 reference in unprocessed classes.

---
 .../parser/properties/__init__.py             | 42 +++++++++++++++++++
 1 file changed, 42 insertions(+)

diff --git a/openapi_python_client/parser/properties/__init__.py b/openapi_python_client/parser/properties/__init__.py
index 839ef05ff..b7cca9e77 100644
--- a/openapi_python_client/parser/properties/__init__.py
+++ b/openapi_python_client/parser/properties/__init__.py
@@ -9,6 +9,7 @@
     "property_from_data",
 ]
 
+from copy import deepcopy
 from itertools import chain
 from typing import Any, ClassVar, Dict, Generic, Iterable, Iterator, List, Optional, Set, Tuple, TypeVar, Union
 
@@ -592,6 +593,13 @@ def build_schemas(
             if isinstance(ref_path, ParseError):
                 schemas.errors.append(PropertyError(detail=ref_path.detail, data=data))
                 continue
+
+            indirect_references = _get_indirect_references(data=data, schemas=schemas)
+            # Create classes wi can be re
+            schemas = build_classes_without_properties(
+                indirect_references=indirect_references, components=components, schemas=schemas, config=config
+            )
+
             schemas_or_err = update_schemas_with_data(ref_path=ref_path, data=data, schemas=schemas, config=config)
             if isinstance(schemas_or_err, PropertyError):
                 next_round.append((name, data))
@@ -603,3 +611,37 @@ def build_schemas(
 
     schemas.errors.extend(errors)
     return schemas
+
+
+def _get_indirect_references(data: oai.Schema, schemas: Schemas) -> Set[str]:
+    """Gets references to unprocessed classes."""
+    if data.properties:
+        processed_references: Set[str] = set(schemas.classes_by_reference.keys())
+        prop_references: Set[str] = set(prop.ref for prop in data.properties.values() if isinstance(prop, oai.Reference))
+        indirect_references: Set[str] = set(ref.strip('#') for ref in prop_references) - processed_references
+        return indirect_references
+    return set()
+
+
+def build_classes_without_properties(
+    indirect_references: Set[str], components: Dict[str, Union[oai.Reference, oai.Schema]], schemas: Schemas, config: Config
+) -> Union[Schemas, PropertyError]:
+    """Adds classes with empty properties. This allows to reference these classes.
+    Properties will be filled in later.
+    """
+    for reference in indirect_references:
+        prop_name = reference.rsplit(sep='/', maxsplit=1)[1]
+        if prop_name not in components:
+            return PropertyError(detail=f"Could not find reference in parsed models or enums: #/components/schemas/{prop_name}")
+
+        prop_ref_path = parse_reference_path(f"#/components/schemas/{prop_name}")
+        data = deepcopy(components.get(prop_name))
+        # Add model for reference without properties. Properties will be added later by order.
+        data.properties = None
+
+        schemas_or_err = update_schemas_with_data(ref_path=prop_ref_path, data=data, schemas=schemas, config=config)
+        if isinstance(schemas_or_err, ParseError):
+            schemas.errors.append(schemas_or_err)
+            continue
+        schemas = schemas_or_err
+    return schemas

From fa899031737c3668141c3d949ffdd2dd44f68b20 Mon Sep 17 00:00:00 2001
From: Matvey <38750524+mtovts@users.noreply.github.com>
Date: Fri, 13 Aug 2021 11:53:13 +0300
Subject: [PATCH 02/11] Remove `Attempted to generate duplicate models` check

---
 openapi_python_client/parser/properties/model_property.py | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/openapi_python_client/parser/properties/model_property.py b/openapi_python_client/parser/properties/model_property.py
index aab642f0d..eec1bb64a 100644
--- a/openapi_python_client/parser/properties/model_property.py
+++ b/openapi_python_client/parser/properties/model_property.py
@@ -255,9 +255,6 @@ def build_model_property(
         additional_properties=additional_properties,
         python_name=utils.PythonIdentifier(value=name, prefix=config.field_prefix),
     )
-    if class_info.name in schemas.classes_by_name:
-        error = PropertyError(data=data, detail=f'Attempted to generate duplicate models with name "{class_info.name}"')
-        return error, schemas
 
     schemas = attr.evolve(schemas, classes_by_name={**schemas.classes_by_name, class_info.name: prop})
     return prop, schemas

From c34169eb07b1679b832ce2f75f81b14993514c0b Mon Sep 17 00:00:00 2001
From: Matvey <38750524+mtovts@users.noreply.github.com>
Date: Fri, 13 Aug 2021 11:53:21 +0300
Subject: [PATCH 03/11] Remove `Attempted to generate duplicate models` test

---
 .../test_properties/test_model_property.py          | 13 -------------
 1 file changed, 13 deletions(-)

diff --git a/tests/test_parser/test_properties/test_model_property.py b/tests/test_parser/test_properties/test_model_property.py
index 0b5a729d1..a610b0170 100644
--- a/tests/test_parser/test_properties/test_model_property.py
+++ b/tests/test_parser/test_properties/test_model_property.py
@@ -127,19 +127,6 @@ def test_happy_path(self, model_property_factory, string_property_factory, date_
             additional_properties=True,
         )
 
-    def test_model_name_conflict(self):
-        from openapi_python_client.parser.properties import Schemas, build_model_property
-
-        data = oai.Schema.construct()
-        schemas = Schemas(classes_by_name={"OtherModel": None})
-
-        err, new_schemas = build_model_property(
-            data=data, name="OtherModel", schemas=schemas, required=True, parent_name=None, config=Config()
-        )
-
-        assert new_schemas == schemas
-        assert err == PropertyError(detail='Attempted to generate duplicate models with name "OtherModel"', data=data)
-
     def test_bad_props_return_error(self):
         from openapi_python_client.parser.properties import Schemas, build_model_property
 

From 3ccec6afc0172f6ffd2c85d1c431c4d5be2f871a Mon Sep 17 00:00:00 2001
From: Matvey <38750524+mtovts@users.noreply.github.com>
Date: Fri, 13 Aug 2021 15:33:01 +0300
Subject: [PATCH 04/11] Add support for recursive references

---
 openapi_python_client/parser/properties/model_property.py | 3 +++
 openapi_python_client/templates/model.py.jinja            | 4 ++--
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/openapi_python_client/parser/properties/model_property.py b/openapi_python_client/parser/properties/model_property.py
index eec1bb64a..f4c438154 100644
--- a/openapi_python_client/parser/properties/model_property.py
+++ b/openapi_python_client/parser/properties/model_property.py
@@ -171,6 +171,9 @@ def _add_if_no_conflict(new_prop: Property) -> Optional[PropertyError]:
             optional_properties.append(prop)
         relative_imports.update(prop.get_imports(prefix=".."))
 
+    # Except circular import
+    relative_imports = {relative_import for relative_import in relative_imports if "import " + class_name + "\n" not in relative_import}
+
     return _PropertyData(
         optional_props=optional_properties,
         required_props=required_properties,
diff --git a/openapi_python_client/templates/model.py.jinja b/openapi_python_client/templates/model.py.jinja
index c4c23c878..306ed4527 100644
--- a/openapi_python_client/templates/model.py.jinja
+++ b/openapi_python_client/templates/model.py.jinja
@@ -31,12 +31,12 @@ class {{ class_name }}:
     """ {{ model.description }} """
     {% for property in model.required_properties + model.optional_properties %}
     {% if property.default is none and property.required %}
-    {{ property.to_string() }}
+    {{ property.to_string().replace(" " + class_name + "]", " T]") }}
     {% endif %}
     {% endfor %}
     {% for property in model.required_properties + model.optional_properties %}
     {% if property.default is not none or not property.required %}
-    {{ property.to_string() }}
+    {{ property.to_string().replace(" " + class_name + "]", " T]") }}
     {% endif %}
     {% endfor %}
     {% if model.additional_properties %}

From 3d6515d4224997f4f91715a319dcb90f20890949 Mon Sep 17 00:00:00 2001
From: Matvey <38750524+mtovts@users.noreply.github.com>
Date: Fri, 13 Aug 2021 15:50:29 +0300
Subject: [PATCH 05/11] Fix circular import

---
 openapi_python_client/parser/properties/model_property.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/openapi_python_client/parser/properties/model_property.py b/openapi_python_client/parser/properties/model_property.py
index f4c438154..4aa75ba92 100644
--- a/openapi_python_client/parser/properties/model_property.py
+++ b/openapi_python_client/parser/properties/model_property.py
@@ -172,7 +172,7 @@ def _add_if_no_conflict(new_prop: Property) -> Optional[PropertyError]:
         relative_imports.update(prop.get_imports(prefix=".."))
 
     # Except circular import
-    relative_imports = {relative_import for relative_import in relative_imports if "import " + class_name + "\n" not in relative_import}
+    relative_imports = {relative_import for relative_import in relative_imports if not relative_import.endswith("import " + class_name)}
 
     return _PropertyData(
         optional_props=optional_properties,

From 98dc19abe6135edbf09a22b206319d7e1fdae37f Mon Sep 17 00:00:00 2001
From: Matvey <38750524+mtovts@users.noreply.github.com>
Date: Fri, 13 Aug 2021 11:51:40 +0300
Subject: [PATCH 06/11] Add the creation of empty classes. It allows to
 reference in unprocessed classes.

---
 .../parser/properties/__init__.py             | 42 +++++++++++++++++++
 1 file changed, 42 insertions(+)

diff --git a/openapi_python_client/parser/properties/__init__.py b/openapi_python_client/parser/properties/__init__.py
index b1701959f..1dbcdb728 100644
--- a/openapi_python_client/parser/properties/__init__.py
+++ b/openapi_python_client/parser/properties/__init__.py
@@ -9,6 +9,7 @@
     "property_from_data",
 ]
 
+from copy import deepcopy
 from itertools import chain
 from typing import Any, ClassVar, Dict, Generic, Iterable, Iterator, List, Optional, Set, Tuple, TypeVar, Union
 
@@ -654,6 +655,13 @@ def build_schemas(
             if isinstance(ref_path, ParseError):
                 schemas.errors.append(PropertyError(detail=ref_path.detail, data=data))
                 continue
+
+            indirect_references = _get_indirect_references(data=data, schemas=schemas)
+            # Create classes wi can be re
+            schemas = build_classes_without_properties(
+                indirect_references=indirect_references, components=components, schemas=schemas, config=config
+            )
+
             schemas_or_err = update_schemas_with_data(ref_path=ref_path, data=data, schemas=schemas, config=config)
             if isinstance(schemas_or_err, PropertyError):
                 next_round.append((name, data))
@@ -665,3 +673,37 @@ def build_schemas(
 
     schemas.errors.extend(errors)
     return schemas
+
+
+def _get_indirect_references(data: oai.Schema, schemas: Schemas) -> Set[str]:
+    """Gets references to unprocessed classes."""
+    if data.properties:
+        processed_references: Set[str] = set(schemas.classes_by_reference.keys())
+        prop_references: Set[str] = set(prop.ref for prop in data.properties.values() if isinstance(prop, oai.Reference))
+        indirect_references: Set[str] = set(ref.strip('#') for ref in prop_references) - processed_references
+        return indirect_references
+    return set()
+
+
+def build_classes_without_properties(
+    indirect_references: Set[str], components: Dict[str, Union[oai.Reference, oai.Schema]], schemas: Schemas, config: Config
+) -> Union[Schemas, PropertyError]:
+    """Adds classes with empty properties. This allows to reference these classes.
+    Properties will be filled in later.
+    """
+    for reference in indirect_references:
+        prop_name = reference.rsplit(sep='/', maxsplit=1)[1]
+        if prop_name not in components:
+            return PropertyError(detail=f"Could not find reference in parsed models or enums: #/components/schemas/{prop_name}")
+
+        prop_ref_path = parse_reference_path(f"#/components/schemas/{prop_name}")
+        data = deepcopy(components.get(prop_name))
+        # Add model for reference without properties. Properties will be added later by order.
+        data.properties = None
+
+        schemas_or_err = update_schemas_with_data(ref_path=prop_ref_path, data=data, schemas=schemas, config=config)
+        if isinstance(schemas_or_err, ParseError):
+            schemas.errors.append(schemas_or_err)
+            continue
+        schemas = schemas_or_err
+    return schemas

From d832f3f91b7540678c332a09e6d0fa1ab9a09978 Mon Sep 17 00:00:00 2001
From: Matvey <38750524+mtovts@users.noreply.github.com>
Date: Fri, 13 Aug 2021 11:53:13 +0300
Subject: [PATCH 07/11] Remove `Attempted to generate duplicate models` check

---
 openapi_python_client/parser/properties/model_property.py | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/openapi_python_client/parser/properties/model_property.py b/openapi_python_client/parser/properties/model_property.py
index 0cfb7a902..d5649c88a 100644
--- a/openapi_python_client/parser/properties/model_property.py
+++ b/openapi_python_client/parser/properties/model_property.py
@@ -257,9 +257,6 @@ def build_model_property(
         additional_properties=additional_properties,
         python_name=utils.PythonIdentifier(value=name, prefix=config.field_prefix),
     )
-    if class_info.name in schemas.classes_by_name:
-        error = PropertyError(data=data, detail=f'Attempted to generate duplicate models with name "{class_info.name}"')
-        return error, schemas
 
     schemas = attr.evolve(schemas, classes_by_name={**schemas.classes_by_name, class_info.name: prop})
     return prop, schemas

From 6747f07b40543bf5b12355c4cadbadbf807345cf Mon Sep 17 00:00:00 2001
From: Matvey <38750524+mtovts@users.noreply.github.com>
Date: Fri, 13 Aug 2021 11:53:21 +0300
Subject: [PATCH 08/11] Remove `Attempted to generate duplicate models` test

---
 .../test_properties/test_model_property.py          | 13 -------------
 1 file changed, 13 deletions(-)

diff --git a/tests/test_parser/test_properties/test_model_property.py b/tests/test_parser/test_properties/test_model_property.py
index 5f179eab2..757f2c99d 100644
--- a/tests/test_parser/test_properties/test_model_property.py
+++ b/tests/test_parser/test_properties/test_model_property.py
@@ -127,19 +127,6 @@ def test_happy_path(self, model_property_factory, string_property_factory, date_
             additional_properties=True,
         )
 
-    def test_model_name_conflict(self):
-        from openapi_python_client.parser.properties import Schemas, build_model_property
-
-        data = oai.Schema.construct()
-        schemas = Schemas(classes_by_name={"OtherModel": None})
-
-        err, new_schemas = build_model_property(
-            data=data, name="OtherModel", schemas=schemas, required=True, parent_name=None, config=Config()
-        )
-
-        assert new_schemas == schemas
-        assert err == PropertyError(detail='Attempted to generate duplicate models with name "OtherModel"', data=data)
-
     def test_bad_props_return_error(self):
         from openapi_python_client.parser.properties import Schemas, build_model_property
 

From e926ad67c6437e96281e6a835910e710e3c28adc Mon Sep 17 00:00:00 2001
From: Matvey <38750524+mtovts@users.noreply.github.com>
Date: Fri, 13 Aug 2021 15:33:01 +0300
Subject: [PATCH 09/11] Add support for recursive references

---
 openapi_python_client/parser/properties/model_property.py | 3 +++
 openapi_python_client/templates/model.py.jinja            | 4 ++--
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/openapi_python_client/parser/properties/model_property.py b/openapi_python_client/parser/properties/model_property.py
index d5649c88a..15b467ee1 100644
--- a/openapi_python_client/parser/properties/model_property.py
+++ b/openapi_python_client/parser/properties/model_property.py
@@ -173,6 +173,9 @@ def _add_if_no_conflict(new_prop: Property) -> Optional[PropertyError]:
             optional_properties.append(prop)
         relative_imports.update(prop.get_imports(prefix=".."))
 
+    # Except circular import
+    relative_imports = {relative_import for relative_import in relative_imports if "import " + class_name + "\n" not in relative_import}
+
     return _PropertyData(
         optional_props=optional_properties,
         required_props=required_properties,
diff --git a/openapi_python_client/templates/model.py.jinja b/openapi_python_client/templates/model.py.jinja
index c4c23c878..306ed4527 100644
--- a/openapi_python_client/templates/model.py.jinja
+++ b/openapi_python_client/templates/model.py.jinja
@@ -31,12 +31,12 @@ class {{ class_name }}:
     """ {{ model.description }} """
     {% for property in model.required_properties + model.optional_properties %}
     {% if property.default is none and property.required %}
-    {{ property.to_string() }}
+    {{ property.to_string().replace(" " + class_name + "]", " T]") }}
     {% endif %}
     {% endfor %}
     {% for property in model.required_properties + model.optional_properties %}
     {% if property.default is not none or not property.required %}
-    {{ property.to_string() }}
+    {{ property.to_string().replace(" " + class_name + "]", " T]") }}
     {% endif %}
     {% endfor %}
     {% if model.additional_properties %}

From f11e4374c9979bb7026824fea36decf5b26fdcc2 Mon Sep 17 00:00:00 2001
From: Matvey <38750524+mtovts@users.noreply.github.com>
Date: Fri, 13 Aug 2021 15:50:29 +0300
Subject: [PATCH 10/11] Fix circular import

---
 openapi_python_client/parser/properties/model_property.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/openapi_python_client/parser/properties/model_property.py b/openapi_python_client/parser/properties/model_property.py
index 15b467ee1..91db268ed 100644
--- a/openapi_python_client/parser/properties/model_property.py
+++ b/openapi_python_client/parser/properties/model_property.py
@@ -174,7 +174,7 @@ def _add_if_no_conflict(new_prop: Property) -> Optional[PropertyError]:
         relative_imports.update(prop.get_imports(prefix=".."))
 
     # Except circular import
-    relative_imports = {relative_import for relative_import in relative_imports if "import " + class_name + "\n" not in relative_import}
+    relative_imports = {relative_import for relative_import in relative_imports if not relative_import.endswith("import " + class_name)}
 
     return _PropertyData(
         optional_props=optional_properties,

From 559bc881dd6849cc64bb9e1d52011a2fc24d86c0 Mon Sep 17 00:00:00 2001
From: Matvey <38750524+mtovts@users.noreply.github.com>
Date: Tue, 17 Aug 2021 14:08:09 +0300
Subject: [PATCH 11/11] Refactor: create empty models then adds properties

---
 .../parser/properties/__init__.py             | 88 +++++++------------
 .../parser/properties/model_property.py       | 75 ++++++++++------
 2 files changed, 80 insertions(+), 83 deletions(-)

diff --git a/openapi_python_client/parser/properties/__init__.py b/openapi_python_client/parser/properties/__init__.py
index 1dbcdb728..315284184 100644
--- a/openapi_python_client/parser/properties/__init__.py
+++ b/openapi_python_client/parser/properties/__init__.py
@@ -11,7 +11,7 @@
 
 from copy import deepcopy
 from itertools import chain
-from typing import Any, ClassVar, Dict, Generic, Iterable, Iterator, List, Optional, Set, Tuple, TypeVar, Union
+from typing import Any, ClassVar, Dict, Generic, Iterator, List, Optional, Set, Tuple, TypeVar, Union
 
 import attr
 
@@ -637,71 +637,49 @@ def build_schemas(
     *, components: Dict[str, Union[oai.Reference, oai.Schema]], schemas: Schemas, config: Config
 ) -> Schemas:
     """Get a list of Schemas from an OpenAPI dict"""
-    to_process: Iterable[Tuple[str, Union[oai.Reference, oai.Schema]]] = components.items()
-    still_making_progress = True
     errors: List[PropertyError] = []
 
-    # References could have forward References so keep going as long as we are making progress
-    while still_making_progress:
-        still_making_progress = False
-        errors = []
-        next_round = []
-        # Only accumulate errors from the last round, since we might fix some along the way
-        for name, data in to_process:
-            if isinstance(data, oai.Reference):
-                schemas.errors.append(PropertyError(data=data, detail="Reference schemas are not supported."))
-                continue
-            ref_path = parse_reference_path(f"#/components/schemas/{name}")
-            if isinstance(ref_path, ParseError):
-                schemas.errors.append(PropertyError(detail=ref_path.detail, data=data))
-                continue
-
-            indirect_references = _get_indirect_references(data=data, schemas=schemas)
-            # Create classes wi can be re
-            schemas = build_classes_without_properties(
-                indirect_references=indirect_references, components=components, schemas=schemas, config=config
-            )
-
-            schemas_or_err = update_schemas_with_data(ref_path=ref_path, data=data, schemas=schemas, config=config)
-            if isinstance(schemas_or_err, PropertyError):
-                next_round.append((name, data))
-                errors.append(schemas_or_err)
-                continue
-            schemas = schemas_or_err
-            still_making_progress = True
-        to_process = next_round
+    # Create classes witch can be referenced
+    schemas = build_schemas_without_properties(components=components, schemas=schemas, config=config)
 
-    schemas.errors.extend(errors)
-    return schemas
+    for name, data in components.items():
+        if isinstance(data, oai.Reference):
+            schemas.errors.append(PropertyError(data=data, detail="Reference schemas are not supported."))
+            continue
+        ref_path = parse_reference_path(f"#/components/schemas/{name}")
+        if isinstance(ref_path, ParseError):
+            schemas.errors.append(PropertyError(detail=ref_path.detail, data=data))
+            continue
 
+        schemas_or_err = update_schemas_with_data(ref_path=ref_path, data=data, schemas=schemas, config=config)
+        if isinstance(schemas_or_err, PropertyError):
+            errors.append(schemas_or_err)
+            continue
+        schemas = schemas_or_err
 
-def _get_indirect_references(data: oai.Schema, schemas: Schemas) -> Set[str]:
-    """Gets references to unprocessed classes."""
-    if data.properties:
-        processed_references: Set[str] = set(schemas.classes_by_reference.keys())
-        prop_references: Set[str] = set(prop.ref for prop in data.properties.values() if isinstance(prop, oai.Reference))
-        indirect_references: Set[str] = set(ref.strip('#') for ref in prop_references) - processed_references
-        return indirect_references
-    return set()
+    return schemas
 
 
-def build_classes_without_properties(
-    indirect_references: Set[str], components: Dict[str, Union[oai.Reference, oai.Schema]], schemas: Schemas, config: Config
-) -> Union[Schemas, PropertyError]:
+def build_schemas_without_properties(
+    components: Dict[str, Union[oai.Reference, oai.Schema]],
+    schemas: Schemas,
+    config: Config,
+) -> Schemas:
     """Adds classes with empty properties. This allows to reference these classes.
     Properties will be filled in later.
     """
-    for reference in indirect_references:
-        prop_name = reference.rsplit(sep='/', maxsplit=1)[1]
-        if prop_name not in components:
-            return PropertyError(detail=f"Could not find reference in parsed models or enums: #/components/schemas/{prop_name}")
-
-        prop_ref_path = parse_reference_path(f"#/components/schemas/{prop_name}")
-        data = deepcopy(components.get(prop_name))
-        # Add model for reference without properties. Properties will be added later by order.
-        data.properties = None
+    for name, schema in components.items():
+        data = deepcopy(schema)
+        if isinstance(data, oai.Reference):
+            # Unsupported now. Adds to errors in the top loop.
+            continue
+        ref_path = parse_reference_path(f"#/components/schemas/{name}")
+        if isinstance(ref_path, ParseError):
+            continue
 
-        schemas_or_err = update_schemas_with_data(ref_path=prop_ref_path, data=data, schemas=schemas, config=config)
+        # Add model for reference without properties. Properties will be added later.
+        data.properties = None
+        schemas_or_err = update_schemas_with_data(ref_path=ref_path, data=data, schemas=schemas, config=config)
         if isinstance(schemas_or_err, ParseError):
             schemas.errors.append(schemas_or_err)
             continue
diff --git a/openapi_python_client/parser/properties/model_property.py b/openapi_python_client/parser/properties/model_property.py
index 91db268ed..9b5410f5e 100644
--- a/openapi_python_client/parser/properties/model_property.py
+++ b/openapi_python_client/parser/properties/model_property.py
@@ -173,8 +173,10 @@ def _add_if_no_conflict(new_prop: Property) -> Optional[PropertyError]:
             optional_properties.append(prop)
         relative_imports.update(prop.get_imports(prefix=".."))
 
-    # Except circular import
-    relative_imports = {relative_import for relative_import in relative_imports if not relative_import.endswith("import " + class_name)}
+    # Except self import
+    relative_imports = {
+        relative_import for relative_import in relative_imports if not relative_import.endswith("import " + class_name)
+    }
 
     return _PropertyData(
         optional_props=optional_properties,
@@ -214,6 +216,15 @@ def _get_additional_properties(
     return additional_properties, schemas
 
 
+def _get_empty_properties(schemas: Schemas) -> _PropertyData:
+    return _PropertyData(
+        optional_props=[],
+        required_props=[],
+        relative_imports=set(),
+        schemas=schemas,
+    )
+
+
 def build_model_property(
     *, data: oai.Schema, name: str, schemas: Schemas, required: bool, parent_name: Optional[str], config: Config
 ) -> Tuple[Union[ModelProperty, PropertyError], Schemas]:
@@ -234,32 +245,40 @@ def build_model_property(
         class_string = f"{utils.pascal_case(parent_name)}{utils.pascal_case(class_string)}"
     class_info = Class.from_string(string=class_string, config=config)
 
-    property_data = _process_properties(data=data, schemas=schemas, class_name=class_info.name, config=config)
-    if isinstance(property_data, PropertyError):
-        return property_data, schemas
-    schemas = property_data.schemas
-
-    additional_properties, schemas = _get_additional_properties(
-        schema_additional=data.additionalProperties, schemas=schemas, class_name=class_info.name, config=config
-    )
-    if isinstance(additional_properties, Property):
-        property_data.relative_imports.update(additional_properties.get_imports(prefix=".."))
-    elif isinstance(additional_properties, PropertyError):
-        return additional_properties, schemas
-
-    prop = ModelProperty(
-        class_info=class_info,
-        required_properties=property_data.required_props,
-        optional_properties=property_data.optional_props,
-        relative_imports=property_data.relative_imports,
-        description=data.description or "",
-        default=None,
-        nullable=data.nullable,
-        required=required,
-        name=name,
-        additional_properties=additional_properties,
-        python_name=utils.PythonIdentifier(value=name, prefix=config.field_prefix),
-    )
+    existing = schemas.classes_by_name.get(class_info.name)
+    if isinstance(existing, ModelProperty):
+        property_data = _process_properties(data=data, schemas=schemas, class_name=class_info.name, config=config)
+        if isinstance(property_data, PropertyError):
+            return property_data, schemas
+        schemas = property_data.schemas
+        prop = attr.evolve(
+            existing,
+            required_properties=property_data.required_props,
+            optional_properties=property_data.optional_props,
+        )
+    else:
+        property_data = _get_empty_properties(schemas=schemas)
+        additional_properties, schemas = _get_additional_properties(
+            schema_additional=data.additionalProperties, schemas=schemas, class_name=class_info.name, config=config
+        )
+        if isinstance(additional_properties, Property):
+            property_data.relative_imports.update(additional_properties.get_imports(prefix=".."))
+        elif isinstance(additional_properties, PropertyError):
+            return additional_properties, schemas
+
+        prop = ModelProperty(
+            class_info=class_info,
+            required_properties=property_data.required_props,
+            optional_properties=property_data.optional_props,
+            relative_imports=property_data.relative_imports,
+            description=data.description or "",
+            default=None,
+            nullable=data.nullable,
+            required=required,
+            name=name,
+            additional_properties=additional_properties,
+            python_name=utils.PythonIdentifier(value=name, prefix=config.field_prefix),
+        )
 
     schemas = attr.evolve(schemas, classes_by_name={**schemas.classes_by_name, class_info.name: prop})
     return prop, schemas