Release 0.21.5 (#1115)

> [!IMPORTANT]
> Merging this pull request will create this release

## Features

### Improved property-merging behavior with `allOf`

When using `allOf` to extend a base object type, `openapi-python-client`
is now able to handle some kinds of modifications to an existing
property that would have previously caused an error:

- Overriding attributes that do not affect validation, such as
`description`.
- Combining properties that this generator ignores, like `maxLength` or
`pattern`.
- Combining a generic numeric type with `int` (resulting in `int`).
- Adding a `format` to a string.
- Combining `any` with a specific type (resulting in that specific
type).
- Adding or overriding a `default`

> [!NOTE]
> `pattern` and `max_length` are no longer fields on `StringProperty`,
which may impact custom templates.

This also fixes a bug where properties of inline objects (as opposed to
references) were not using the
merge logic, but were simply overwriting previous definitions of the
same property.

## Fixes

- Allow default values for properties of `Any` type

### Produce valid code for an object that has no properties at all

Fixed by PR #1109. Thanks @eli-bl!

Co-authored-by: knope-bot[bot] <152252888+knope-bot[bot]@users.noreply.github.com>

Author: knope-bot[bot]

.changeset/allow_default_values_for_properties_of_any_type.md

@@ -13,6 +13,35 @@ Programmatic usage of this project (e.g., importing it as a Python module) and t
 
 The 0.x prefix used in versions for this project is to indicate that breaking changes are expected frequently (several times a year). Breaking changes will increment the minor number, all other changes will increment the patch number. You can track the progress toward 1.0 [here](https://github.com/openapi-generators/openapi-python-client/projects/2).
 
+## 0.21.5 (2024-09-07)
+
+### Features
+
+#### Improved property-merging behavior with `allOf`
+
+When using `allOf` to extend a base object type, `openapi-python-client` is now able to handle some kinds of modifications to an existing property that would have previously caused an error:
+
+- Overriding attributes that do not affect validation, such as `description`.
+- Combining properties that this generator ignores, like `maxLength` or `pattern`.
+- Combining a generic numeric type with `int` (resulting in `int`).
+- Adding a `format` to a string.
+- Combining `any` with a specific type (resulting in that specific type).
+- Adding or overriding a `default`
+
+> [!NOTE]
+> `pattern` and `max_length` are no longer fields on `StringProperty`, which may impact custom templates.
+
+This also fixes a bug where properties of inline objects (as opposed to references) were not using the
+merge logic, but were simply overwriting previous definitions of the same property.
+
+### Fixes
+
+- Allow default values for properties of `Any` type
+
+#### Produce valid code for an object that has no properties at all
+
+Fixed by PR #1109. Thanks @eli-bl!
+
 ## 0.21.4 (2024-08-25)
 
 ### Fixes

.changeset/improved_property_merging.md

@@ -18,7 +18,7 @@ dependencies = [
     "typing-extensions>=4.8.0,<5.0.0",
 ]
 name = "openapi-python-client"
-version = "0.21.4"
+version = "0.21.5"
 description = "Generate modern Python clients from OpenAPI"
 keywords = [
     "OpenAPI",