From: Sebastián Ramírez <tiangolo@gmail.com>
Date: Wed, 19 Nov 2025 16:50:18 +0000 (+0100)
Subject: ♻️ Make the result of `Depends()` and `Security()` hashable, as a workaround for... 
X-Git-Tag: 0.121.3~2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=85701631a0241c5f02b4940734a5428f66abe167;p=thirdparty%2Ffastapi%2Ffastapi.git

♻️ Make the result of `Depends()` and `Security()` hashable, as a workaround for other tools interacting with these internal parts (#14372)
---

diff --git a/fastapi/dependencies/utils.py b/fastapi/dependencies/utils.py
index 4b69e39a15..1e92c1ba2a 100644
--- a/fastapi/dependencies/utils.py
+++ b/fastapi/dependencies/utils.py
@@ -1,3 +1,4 @@
+import dataclasses
 import inspect
 from contextlib import AsyncExitStack, contextmanager
 from copy import copy, deepcopy
@@ -428,7 +429,7 @@ def analyze_param(
     if depends is not None and depends.dependency is None:
         # Copy `depends` before mutating it
         depends = copy(depends)
-        depends.dependency = type_annotation
+        depends = dataclasses.replace(depends, dependency=type_annotation)
 
     # Handle non-param type annotations like Request
     if lenient_issubclass(
diff --git a/fastapi/params.py b/fastapi/params.py
index 6a58d5808e..6d07df35e1 100644
--- a/fastapi/params.py
+++ b/fastapi/params.py
@@ -762,13 +762,13 @@ class File(Form):  # type: ignore[misc]
         )
 
 
-@dataclass
+@dataclass(frozen=True)
 class Depends:
     dependency: Optional[Callable[..., Any]] = None
     use_cache: bool = True
     scope: Union[Literal["function", "request"], None] = None
 
 
-@dataclass
+@dataclass(frozen=True)
 class Security(Depends):
     scopes: Optional[Sequence[str]] = None
diff --git a/tests/test_depends_hashable.py b/tests/test_depends_hashable.py
new file mode 100644
index 0000000000..d57f2726ec
--- /dev/null
+++ b/tests/test_depends_hashable.py
@@ -0,0 +1,25 @@
+# This is more or less a workaround to make Depends and Security hashable
+# as other tools that use them depend on that
+# Ref: https://github.com/fastapi/fastapi/pull/14320
+
+from fastapi import Depends, Security
+
+
+def dep():
+    pass
+
+
+def test_depends_hashable():
+    dep()  # just for coverage
+    d1 = Depends(dep)
+    d2 = Depends(dep)
+    d3 = Depends(dep, scope="function")
+    d4 = Depends(dep, scope="function")
+
+    s1 = Security(dep)
+    s2 = Security(dep)
+
+    assert hash(d1) == hash(d2)
+    assert hash(s1) == hash(s2)
+    assert hash(d1) != hash(d3)
+    assert hash(d3) == hash(d4)