Add CI coverage for Python 3.15 (#5127)

Author: JelleZijlstra

.github/workflows/fuzz.yml

@@ -24,6 +24,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
+        # TODO: add 3.15; relies on libcst which doesn't support 3.15 yet
         python-version: ["3.10", "3.11", "3.12", "3.13", "3.14"]
 
     steps:

.github/workflows/release_tests.yml

@@ -26,7 +26,7 @@ jobs:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        python-version: ["3.12", "3.13", "3.14"]
+        python-version: ["3.12", "3.13", "3.14", "3.15"]
         os: [macOS-latest, ubuntu-latest, windows-latest]
 
     steps:

.github/workflows/test.yml

@@ -37,7 +37,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: ["3.10", "3.11", "3.12.10", "3.13", "3.14", "pypy-3.11"]
+        python-version: ["3.10", "3.11", "3.12.10", "3.13", "3.14", "3.15", "pypy-3.11"]
         os: [ubuntu-latest, macOS-latest, windows-latest, windows-11-arm]
         exclude:
           # setup-python only supports CPython 3.11+ on arm64 windows

CHANGES.md

@@ -37,6 +37,10 @@
 
 <!-- Changes to how Black is packaged, such as dependency requirements -->
 
+- Python 3.15 is now supported. Compiled wheels are not yet provided for Python 3.15, so
+  performance may be slower than on existing Python versions. Wheels will be provided
+  once Python 3.15 is later in its release cycle. (#5127)
+
 ### Parser
 
 <!-- Changes to the parser or to version autodetection -->

pyproject.toml

@@ -49,6 +49,7 @@ classifiers = [
     "Programming Language :: Python :: 3.12",
     "Programming Language :: Python :: 3.13",
     "Programming Language :: Python :: 3.14",
+    "Programming Language :: Python :: 3.15",
     "Topic :: Software Development :: Libraries :: Python Modules",
     "Topic :: Software Development :: Quality Assurance",
 ]

tox.ini

@@ -1,6 +1,6 @@
 [tox]
 isolated_build = true
-envlist = {,ci-}py{310,311,312,313,314,py3},fuzz,run_self,generate_schema
+envlist = {,ci-}py{310,311,312,313,314,315,py3},fuzz,run_self,generate_schema
 
 [testenv]
 setenv =