Drop Python 3.8 support (#642)

Upstream dependencies (e.g. numpy, scipy) have now dropped Python 3.8
support in latest releases.

Add Python 3.11 support.

See also https://dials.github.io/kb/proposals/dc3

---------

Co-authored-by: Nicholas Devenish <ndevenish@gmail.com>

.azure-pipelines/azure-pipelines.yml

@@ -14,11 +14,11 @@ stages:
  steps:
  - checkout: none
 
- # Use Python >=3.8 for syntax validation
+ # Use Python >=3.9 for syntax validation
  - task: UsePythonVersion@0
  displayName: Set up python
  inputs:
- versionSpec: 3.8
+ versionSpec: 3.9
 
  # Run syntax validation on a shallow clone
  - bash: |
@@ -78,7 +78,7 @@ stages:
  vmImage: ubuntu-20.04
  timeoutInMinutes: 60
  variables:
- PYTHON_VERSION: 3.8
+ PYTHON_VERSION: 3.9
  steps:
  - template: unix-build.yml
 
@@ -88,10 +88,10 @@ stages:
  vmImage: ubuntu-20.04
  strategy:
  matrix:
- python38:
- PYTHON_VERSION: 3.8
  python39:
  PYTHON_VERSION: 3.9
+ python311:
+ PYTHON_VERSION: 3.11
  timeoutInMinutes: 60
  steps:
  - template: unix-build.yml
@@ -101,10 +101,10 @@ stages:
  vmImage: macOS-latest
  strategy:
  matrix:
- python38:
- PYTHON_VERSION: 3.8
  python39:
  PYTHON_VERSION: 3.9
+ python311:
+ PYTHON_VERSION: 3.11
  timeoutInMinutes: 60
  steps:
  - template: unix-build.yml
@@ -114,8 +114,10 @@ stages:
  vmImage: windows-2019
  strategy:
  matrix:
- python38:
- PYTHON_VERSION: 3.8
+ python39:
+ PYTHON_VERSION: 3.9
+ python311:
+ PYTHON_VERSION: 3.11
  timeoutInMinutes: 20
  steps:
  - template: windows-build.yml

.azure-pipelines/bootstrap.py

@@ -847,7 +847,7 @@ def run():
  "--python",
  help="Install this minor version of Python (default: %(default)s)",
  default="3.9",
- choices=("3.8", "3.9", "3.10"),
+ choices=("3.9", "3.10", "3.11"),
  )
  parser.add_argument(
  "--branch",

newsfragments/642.misc

@@ -0,0 +1 @@
+Drop Python 3.8 support in line with https://dials.github.io/kb/proposals/dc3. Add Python 3.11 support.

setup.cfg

@@ -8,8 +8,9 @@ classifiers =
  Operating System :: Microsoft :: Windows
  Operating System :: POSIX :: Linux
  Programming Language :: Python :: 3
- Programming Language :: Python :: 3.8
  Programming Language :: Python :: 3.9
+ Programming Language :: Python :: 3.10
+ Programming Language :: Python :: 3.11
 
 [flake8]
 # Black disagrees with flake8 on a few points. Ignore those.