Remove support for Python before 3.10

.gitlab-ci.yml

@@ -49,16 +49,6 @@ before_script:
   needs: ["build"]
   <<: *python-cache
 
-unit-tests:python-3.8:
-  <<: *unit-tests
-  variables:
-    PYTHON_VERSION: '3.8-bullseye'
-
-unit-tests:python-3.9:
-  <<: *unit-tests
-  variables:
-    PYTHON_VERSION: '3.9-bullseye'
-
 unit-tests:python-3.10:
   <<: *unit-tests
   variables:
@@ -85,16 +75,6 @@ unit-tests:python-3.10:
   needs: ["build"]
   <<: *python-cache
 
-nightly-tests:python-3.8:
-  extends: .nightly-tests
-  variables:
-    PYTHON_VERSION: '3.8-bullseye'
-
-nightly-tests:python-3.9:
-  extends: .nightly-tests
-  variables:
-    PYTHON_VERSION: '3.9-bullseye'
-
 nightly-tests:python-3.10:
   extends: .nightly-tests
   variables:

.pre-commit-config.yaml

@@ -19,10 +19,10 @@ repos:
         args: [--fix=lf]
 
   - repo: https://github.com/asottile/pyupgrade
-    rev: v2.31.0
+    rev: v2.31.1
     hooks:
       - id: pyupgrade
-        args: [--py38-plus]
+        args: [--py310-plus]
 
   - repo: https://github.com/PyCQA/isort
     rev: 5.10.1

.readthedocs.yml

@@ -3,10 +3,15 @@
 # SPDX-License-Identifier: LGPL-3.0-or-later
 
 version: 2
+
+build:
+  os: ubuntu-20.04
+  tools:
+    python: "3.10"
+
 sphinx:
   configuration: docs/conf.py
 
 python:
-  version: 3.8
   install:
     - requirements: docs/requirements.txt

README.md

@@ -61,9 +61,12 @@ your system.
 ## Prerequisites
 
 Before you begin, ensure you have met the following requirements:
-- You have installed Python 3.8, 3.9, or 3.10 (we have not yet tested with Python
+- You have installed Python 3.10 (we have not yet tested with Python
   3.11, there might be some problems due to changed internals regarding the byte-code
   instrumentation).
+
+  **Attention:** Pynguin now requires Python 3.10!  Older versions are no longer 
+  supported!
 - You have a recent Linux/macOS/Windows machine.
 
 Please consider reading the [online documentation](https://pynguin.readthedocs.io)

docker/Dockerfile

@@ -13,7 +13,7 @@
 # Build stage for Pynguin
 FROM python:3.10.2-slim-bullseye AS build
 MAINTAINER Stephan Lukasczyk <[email protected]>
-ENV POETRY_VERSION "1.1.12"
+ENV POETRY_VERSION "1.1.13"
 
 WORKDIR /pynguin-build
 

docs/dev/contributing.rst

@@ -59,7 +59,7 @@ In particular, we want to point to Sec. 2.14 of Google's style guide, regarding
 
 Import from ``__future__`` are not permitted except for the ``from __future__ import
 annotations`` feature that allows more concise type hints.  Pynguin requires at least
-Python 3.8—there is not need to support older versions here!
+Python 3.10—there is not need to support older versions here!
 
 Checks
 ^^^^^^

docs/source/_static/queue_example.py

@@ -33,7 +33,7 @@ def enqueue(self, x: int) -> bool:
             self.tail = 0
         return True
 
-    def dequeue(self) -> Optional[int]:
+    def dequeue(self) -> int | None:
         if self.size == 0:
             return None
         x = self.data[self.head]

pynguin/assertion/assertiontraceobserver.py

@@ -7,7 +7,7 @@
 """Provides an abstract observer that can be used to generate assertions."""
 import copy
 from types import ModuleType
-from typing import List, Optional, cast
+from typing import cast
 
 import pynguin.assertion.assertion as ass
 import pynguin.assertion.assertion_trace as at
@@ -30,7 +30,7 @@ class AssertionTraceObserver(ex.ExecutionObserver):
 
     def __init__(self) -> None:
         self._trace: at.AssertionTrace = at.AssertionTrace()
-        self._watch_list: List[vr.VariableReference] = []
+        self._watch_list: list[vr.VariableReference] = []
 
     def clear(self) -> None:
         """Clear the existing gathered trace."""
@@ -59,7 +59,7 @@ def after_statement_execution(
         self,
         statement: st.Statement,
         exec_ctx: ex.ExecutionContext,
-        exception: Optional[Exception] = None,
+        exception: Exception | None = None,
     ) -> None:
         if exception is not None:
             return