GHA: Enable Python 3.14 (#131)

* GitHub Action: Enable Python 3.14

* Upgrade lxml, remove install step of header files
  * Bump lxml to >=6.0.0
  * Upgrade with "uv lock --upgrade-package lxml"
* Fix TimeoutError test for Python 3.14
  * Raise wait time
  * Use a 'fork' context so the child does not need to import the test package
    (spawn/forkserver can fail to import test modules under some Python versions)
* Use the 'fork' start method on platforms
* Introduce PYPROJECT_GROUP=tests in `.github/workflows/ci.yml`

Author: tomschr

.github/workflows/ci.yml

@@ -29,6 +29,8 @@ env:
   UV_FROZEN: "1"
   # Needed for coverage/multiprocessing reliability
   PYTHONSTARTMETHOD: spawn
+  # The group to use for installing/testing dependencies
+  PYPROJECT_GROUP: tests
 
 jobs:
   test-ubuntu:
@@ -40,7 +42,7 @@ jobs:
         python-version: &python-matrix
           - '3.12'
           - '3.13'
-          # - '3.14'
+          - '3.14'
     container:
       image: registry.opensuse.org/documentation/containers/15.6/opensuse-daps-toolchain:latest
     steps:
@@ -81,7 +83,7 @@ jobs:
           cache-dependency-glob: "uv.lock"
 
       - name: Install dependencies and Coverage Tools
-        run: uv sync --group tests
+        run: uv sync --group ${{ env.PYPROJECT_GROUP }}
 
       - name: Run tests and Report Coverage
         env:
@@ -189,7 +191,7 @@ jobs:
           python3 -m venv .venv
           source .venv/bin/activate
           pip install uv
-          uv pip install --editable . --group devel
+          uv pip install --editable . --group ${{ env.PYPROJECT_GROUP }}
 
       # Install macOS-specific external tools (such as XML parsers and Java)
       - name: Install external tools (macOS)

changelog.d/131.infra.rst

@@ -0,0 +1 @@
+Enable Python 3.14 for GitHub Action

pyproject.toml

@@ -22,7 +22,7 @@ license-files = ["LICENSE"]
 dependencies = [
     "click>=8.1.8",
     "jinja2>=3.1.6,<4.0.0",
-    "lxml>=5.4.0",
+    "lxml>=6.0.0",
     "pydantic>=2.11.4",
     "rich>=14.0.0",
     "tomlkit>=0.13.2",
@@ -89,7 +89,6 @@ devel = [
   # {include-group = "publish"},
 ]
 
-
 [project.scripts]
 docbuild = "docbuild.__main__:cli"
 

tests/utils/test_pidlock.py

@@ -88,19 +88,27 @@ def test_lock_prevents_concurrent_access_in_separate_process(lock_setup):
     lock_dir.mkdir()
     lock_path = PidFileLock(resource_path, lock_dir).lock_path
 
+    # Use the 'fork' start method on platforms where it is available.
+    # This avoids issues with importing the 'tests' package in spawned
+    # child processes (e.g. when using forkserver/spawn).
+    try:
+        ctx = mp.get_context("fork")
+    except ValueError:  # pragma: no cover - defensive for non-fork platforms
+        pytest.skip("multiprocessing 'fork' context not available on this platform")
+
     # Create an Event to signal the child process to release the lock
-    done_event = mp.Event()
+    done_event = ctx.Event()
 
     # Start a background process to hold the lock
-    lock_holder = mp.Process(
+    lock_holder = ctx.Process(
         target=_mp_lock_holder, args=(resource_path, lock_dir, lock_path, done_event)
     )
     lock_holder.start()
 
     # Wait for the lock holder to acquire the lock (check for lock file existence)
     timeout_start = time.time()
     while not lock_path.exists():
-        if time.time() - timeout_start > 5:
+        if (time.time() - timeout_start) > 10:
             raise TimeoutError("Child process failed to acquire lock in time.")
         time.sleep(0.01)