From 4d5867d5a235040b3e7d3373a56c5b2b580db7b7 Mon Sep 17 00:00:00 2001
From: Bryan Forbes <bryan@reigndropsfall.net>
Date: Tue, 12 Apr 2022 04:45:37 -0500
Subject: [PATCH] Handle UnionType (#221)
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Co-authored-by: Bernát Gábor <bgabor8@bloomberg.net>
---
 CHANGELOG.md                                              | 1 +
 src/sphinx_autodoc_typehints/__init__.py                  | 2 ++
 tests/roots/test-dummy/dummy_module_future_annotations.py | 4 +++-
 tests/test_sphinx_autodoc_typehints.py                    | 6 ++++--
 4 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 6240a3ba..33bddefe 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -3,6 +3,7 @@
 ## 1.18.0
 
 - Support and require `nptyping>=2`
+- Handle `UnionType`
 
 ## 1.17.1
 
diff --git a/src/sphinx_autodoc_typehints/__init__.py b/src/sphinx_autodoc_typehints/__init__.py
index 9ec89cf1..cde07203 100644
--- a/src/sphinx_autodoc_typehints/__init__.py
+++ b/src/sphinx_autodoc_typehints/__init__.py
@@ -175,6 +175,8 @@ def format_annotation(annotation: Any, config: Config) -> str:  # noqa: C901 # t
         formatted_args = f"\\[\\[{', '.join(fmt[:-1])}], {fmt[-1]}]"
     elif full_name == "typing.Literal":
         formatted_args = f"\\[{', '.join(repr(arg) for arg in args)}]"
+    elif full_name == "types.UnionType":
+        return " | ".join([format_annotation(arg, config) for arg in args])
 
     if args and not formatted_args:
         try:
diff --git a/tests/roots/test-dummy/dummy_module_future_annotations.py b/tests/roots/test-dummy/dummy_module_future_annotations.py
index a84934d0..5cc16cb1 100644
--- a/tests/roots/test-dummy/dummy_module_future_annotations.py
+++ b/tests/roots/test-dummy/dummy_module_future_annotations.py
@@ -1,7 +1,9 @@
 from __future__ import annotations
 
 
-def function_with_py310_annotations(self, x: bool, y: int, z: str | None = None) -> str:  # noqa: U100
+def function_with_py310_annotations(
+    self, x: bool | None, y: int | str | float, z: str | None = None  # noqa: U100
+) -> str:
     """
     Method docstring.
 
diff --git a/tests/test_sphinx_autodoc_typehints.py b/tests/test_sphinx_autodoc_typehints.py
index b87f73ad..b5f0a009 100644
--- a/tests/test_sphinx_autodoc_typehints.py
+++ b/tests/test_sphinx_autodoc_typehints.py
@@ -370,6 +370,8 @@ def set_python_path() -> None:
 def maybe_fix_py310(expected_contents: str) -> str:
     if PY310_PLUS:
         for old, new in [
+            ("*bool** | **None*", '"bool" | "None"'),
+            ("*int** | **str** | **float*", '"int" | "str" | "float"'),
             ("*str** | **None*", '"Optional"["str"]'),
             ("(*bool*)", '("bool")'),
             ("(*int*", '("int"'),
@@ -704,9 +706,9 @@ def test_sphinx_output_future_annotations(app: SphinxTestApp, status: StringIO)
            Method docstring.
 
            Parameters:
-              * **x** (*bool*) -- foo
+              * **x** (*bool** | **None*) -- foo
 
-              * **y** (*int*) -- bar
+              * **y** (*int** | **str** | **float*) -- bar
 
               * **z** (*str** | **None*) -- baz