upgrade GitHub Actions image used for most CI jobs and remove Python 2.7 CI testing

.github/workflows/release.yaml

@@ -93,7 +93,7 @@ jobs:
     needs:
     - release_info
     runs-on:
-    - ubuntu-20.04
+    - ubuntu-22.04
     steps:
     - name: Check out code
       uses: actions/checkout@v3

.github/workflows/test.yaml

@@ -112,7 +112,7 @@ jobs:
     needs:
     - classify_changes
     runs-on:
-    - ubuntu-20.04
+    - ubuntu-22.04
     steps:
     - name: Check out code
       uses: actions/checkout@v4
@@ -373,7 +373,7 @@ jobs:
     needs:
     - classify_changes
     runs-on:
-    - ubuntu-20.04
+    - ubuntu-22.04
     steps:
     - name: Check out code
       uses: actions/checkout@v3
@@ -563,7 +563,7 @@ jobs:
     if: github.repository_owner == 'pantsbuild'
     name: Ensure PR has a category label
     runs-on:
-    - ubuntu-20.04
+    - ubuntu-22.04
     steps:
     - env:
         GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
@@ -581,7 +581,7 @@ jobs:
     needs:
     - classify_changes
     runs-on:
-    - ubuntu-20.04
+    - ubuntu-22.04
     steps:
     - env:
         GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
@@ -608,7 +608,7 @@ jobs:
       release: ${{ steps.classify.outputs.release }}
       rust: ${{ steps.classify.outputs.rust }}
     runs-on:
-    - ubuntu-20.04
+    - ubuntu-22.04
     steps:
     - name: Check out code
       uses: actions/checkout@v4
@@ -630,7 +630,7 @@ jobs:
     - bootstrap_pants_linux_x86_64
     - classify_changes
     runs-on:
-    - ubuntu-20.04
+    - ubuntu-22.04
     steps:
     - name: Check out code
       uses: actions/checkout@v4
@@ -684,7 +684,7 @@ jobs:
     needs:
     - set_merge_ok
     runs-on:
-    - ubuntu-20.04
+    - ubuntu-22.04
     steps:
     - run: "merge_ok=\"${{ needs.set_merge_ok.outputs.merge_ok }}\"\nif [[ \"${merge_ok}\" == \"true\" ]]; then\n    echo\
         \ \"Merge OK\"\n    exit 0\nelse\n    echo \"Merge NOT OK\"\n    exit 1\nfi\n"
@@ -721,7 +721,7 @@ jobs:
     outputs:
       merge_ok: ${{ steps.set_merge_ok.outputs.merge_ok }}
     runs-on:
-    - ubuntu-20.04
+    - ubuntu-22.04
     steps:
     - id: set_merge_ok
       run: echo 'merge_ok=true' >> ${GITHUB_OUTPUT}
@@ -790,7 +790,7 @@ jobs:
     - bootstrap_pants_linux_x86_64
     - classify_changes
     runs-on:
-    - ubuntu-20.04
+    - ubuntu-22.04
     steps:
     - name: Check out code
       uses: actions/checkout@v4
@@ -882,7 +882,7 @@ jobs:
     - bootstrap_pants_linux_x86_64
     - classify_changes
     runs-on:
-    - ubuntu-20.04
+    - ubuntu-22.04
     steps:
     - name: Check out code
       uses: actions/checkout@v4
@@ -974,7 +974,7 @@ jobs:
     - bootstrap_pants_linux_x86_64
     - classify_changes
     runs-on:
-    - ubuntu-20.04
+    - ubuntu-22.04
     steps:
     - name: Check out code
       uses: actions/checkout@v4
@@ -1066,7 +1066,7 @@ jobs:
     - bootstrap_pants_linux_x86_64
     - classify_changes
     runs-on:
-    - ubuntu-20.04
+    - ubuntu-22.04
     steps:
     - name: Check out code
       uses: actions/checkout@v4
@@ -1158,7 +1158,7 @@ jobs:
     - bootstrap_pants_linux_x86_64
     - classify_changes
     runs-on:
-    - ubuntu-20.04
+    - ubuntu-22.04
     steps:
     - name: Check out code
       uses: actions/checkout@v4
@@ -1250,7 +1250,7 @@ jobs:
     - bootstrap_pants_linux_x86_64
     - classify_changes
     runs-on:
-    - ubuntu-20.04
+    - ubuntu-22.04
     steps:
     - name: Check out code
       uses: actions/checkout@v4
@@ -1342,7 +1342,7 @@ jobs:
     - bootstrap_pants_linux_x86_64
     - classify_changes
     runs-on:
-    - ubuntu-20.04
+    - ubuntu-22.04
     steps:
     - name: Check out code
       uses: actions/checkout@v4
@@ -1434,7 +1434,7 @@ jobs:
     - bootstrap_pants_linux_x86_64
     - classify_changes
     runs-on:
-    - ubuntu-20.04
+    - ubuntu-22.04
     steps:
     - name: Check out code
       uses: actions/checkout@v4
@@ -1526,7 +1526,7 @@ jobs:
     - bootstrap_pants_linux_x86_64
     - classify_changes
     runs-on:
-    - ubuntu-20.04
+    - ubuntu-22.04
     steps:
     - name: Check out code
       uses: actions/checkout@v4
@@ -1618,7 +1618,7 @@ jobs:
     - bootstrap_pants_linux_x86_64
     - classify_changes
     runs-on:
-    - ubuntu-20.04
+    - ubuntu-22.04
     steps:
     - name: Check out code
       uses: actions/checkout@v4

docs/notes/2.24.x.md

@@ -16,6 +16,7 @@ We offer [formal sponsorship tiers for companies](https://www.pantsbuild.org/spo
 
 ### Deprecations
 
+- **Python 2.7**: As announced in the v2.23.x release series, Pants v2.24 and later are not proactively tested in CI with Python 2.7 since [Python 2.7 is no longer supported by its maintainers as of 1 January 2020](https://www.python.org/doc/sunset-python-2/). While Pants may continue to work with Python 2.7 in the near term, Pants no longer officially supports use of Python 2.7, and, consequently, any remaining support for Python 2.7 may "bit rot" and diverge over time. Contributions to fix issues with Python 2.7 support will continue to be accepted, but will depend on any community contributions and will not consitute continued official support for Python 2.7.
 
 
 ### General
@@ -26,7 +27,11 @@ We offer [formal sponsorship tiers for companies](https://www.pantsbuild.org/spo
 
 #### Python
 
-The default lockfiles bundled with Pants for various tools (ex: to run `black`) no longer support Python 3.7.  The minimum Python version is now 3.8.  Pants still supports running Python 3.7 (and earlier!) user code, but you will need to [generate your own lockfiles](https://www.pantsbuild.org/stable/docs/python/overview/lockfiles#lockfiles-for-tools).  See the announcement at <https://www.pantsbuild.org/blog/2024/08/24/venerable-pythons> for further context.
+Deprecations:
+
+- Pants v2.24 and later are not proactively tested in CI with Python 2.7 since [Python 2.7 is no longer supported by its maintainers as of 1 January 2020](https://www.python.org/doc/sunset-python-2/). While Pants may continue to work with Python 2.7 in the near term, Pants no longer officially supports use of Python 2.7, and, consequently, any remaining support for Python 2.7 may "bit rot" and diverge over time. Contributions to fix issues with Python 2.7 support will continue to be accepted, but will depend on any community contributions and will not constitute continued official support for Python 2.7.
+
+- The default lockfiles bundled with Pants for various tools (ex: to run `black`) no longer support Python 3.7.  The minimum Python version is now 3.8.  Pants still supports running Python 3.7 (and earlier!) user code, but you will need to [generate your own lockfiles](https://www.pantsbuild.org/stable/docs/python/overview/lockfiles#lockfiles-for-tools).  See the announcement at <https://www.pantsbuild.org/blog/2024/08/24/venerable-pythons> for further context.
 
 As a consequence of the lockfile generation, newer versions of many tools are now included in the default lockfiles.
 

src/python/pants/backend/python/dependency_inference/parse_python_dependencies_test.py

@@ -23,7 +23,6 @@
 from pants.core.util_rules import stripped_source_files
 from pants.engine.addresses import Address
 from pants.testutil.python_interpreter_selection import (
-    skip_unless_python27_present,
     skip_unless_python38_present,
     skip_unless_python39_present,
 )
@@ -439,52 +438,6 @@ def test_handle_unicode(rule_runner: RuleRunner) -> None:
     assert_deps_parsed(rule_runner, "x = 'äbç'", expected_imports={})
 
 
-@skip_unless_python27_present
-def test_works_with_python2(rule_runner: RuleRunner) -> None:
-    content = dedent(
-        """\
-        # -*- coding: utf-8 -*-
-        print "Python 2 lives on."
-
-        import demo
-        from project.demo import Demo
-
-        __import__(u"pkg_resources")
-        __import__(b"treat.as.a.regular.import.not.a.string.import")
-        __import__(u"{}".format("interpolation"))
-
-        importlib.import_module(b"dep.from.bytes")
-        importlib.import_module(u"dep.from.str")
-        importlib.import_module(u"dep.from.str_狗")
-
-        b"\\xa0 a non-utf8 string, make sure we ignore it"
-
-        try: import weak1
-        except ImportError: import strong1
-        else: import strong2
-        finally: import strong3
-        """
-    )
-    assert_deps_parsed(
-        rule_runner,
-        content,
-        constraints="==2.7.*",
-        expected_imports={
-            "demo": ImpInfo(lineno=4, weak=False),
-            "project.demo.Demo": ImpInfo(lineno=5, weak=False),
-            "pkg_resources": ImpInfo(lineno=7, weak=False),
-            "treat.as.a.regular.import.not.a.string.import": ImpInfo(lineno=8, weak=False),
-            "dep.from.bytes": ImpInfo(lineno=11, weak=True),
-            "dep.from.str": ImpInfo(lineno=12, weak=True),
-            "dep.from.str_狗": ImpInfo(lineno=13, weak=True),
-            "weak1": ImpInfo(lineno=17, weak=True),
-            "strong1": ImpInfo(lineno=18, weak=False),
-            "strong2": ImpInfo(lineno=19, weak=False),
-            "strong3": ImpInfo(lineno=20, weak=False),
-        },
-    )
-
-
 @skip_unless_python38_present
 def test_works_with_python38(rule_runner: RuleRunner) -> None:
     content = dedent(

src/python/pants/backend/python/framework/django/dependency_inference_test.py

@@ -20,7 +20,6 @@
 from pants.engine.rules import QueryRule
 from pants.engine.target import InferredDependencies
 from pants.testutil.python_interpreter_selection import (
-    skip_unless_python27_present,
     skip_unless_python38_present,
     skip_unless_python39_present,
 )
@@ -170,12 +169,6 @@ def do_test_implicit_app_dependencies(rule_runner: RuleRunner, constraints: str)
     }
 
 
-@skip_unless_python27_present
-def test_works_with_python2(rule_runner: RuleRunner) -> None:
-    do_test_migration_dependencies(rule_runner, constraints="CPython==2.7.*")
-    do_test_implicit_app_dependencies(rule_runner, constraints="CPython==2.7.*")
-
-
 @skip_unless_python38_present
 def test_works_with_python38(rule_runner: RuleRunner) -> None:
     do_test_migration_dependencies(rule_runner, constraints="CPython==3.8.*")

src/python/pants/backend/python/framework/django/detect_apps_test.py

@@ -13,10 +13,9 @@
 from pants.core.util_rules import stripped_source_files
 from pants.engine.environment import EnvironmentName
 from pants.testutil.python_interpreter_selection import (
-    PY_27,
+    PY_38,
     PY_39,
     skip_unless_all_pythons_present,
-    skip_unless_python27_present,
     skip_unless_python37_present,
     skip_unless_python38_present,
     skip_unless_python39_present,
@@ -52,10 +51,6 @@ def assert_apps_detected(
         py3_only = "async def i_will_parse_on_python3_not_on_python2():\n  pass"
     else:
         py3_only = ""
-    if "2.7" in constraints2:
-        py2_only = "print 'I will parse on Python 2.7, not on Python 3'"
-    else:
-        py2_only = ""
     rule_runner.write_files(
         {
             "path/to/app1/BUILD": softwrap(
@@ -84,9 +79,7 @@ class App1AppConfig(AppConfig):
                 """
             ),
             "another/path/app2/apps.py": softwrap(
-                f"""\
-                {py2_only}
-
+                """\
                 class App2AppConfig(AppConfig):
                     name = "another.path.app2"
                     label = "app2_label"
@@ -124,11 +117,6 @@ class App3AppConfig(AppConfig):
     )
 
 
-@skip_unless_python27_present
-def test_works_with_python2(rule_runner: RuleRunner) -> None:
-    assert_apps_detected(rule_runner, constraints1="CPython==2.7.*")
-
-
 @skip_unless_python37_present
 def test_works_with_python37(rule_runner: RuleRunner) -> None:
     assert_apps_detected(rule_runner, constraints1="CPython==3.7.*")
@@ -144,6 +132,6 @@ def test_works_with_python39(rule_runner: RuleRunner) -> None:
     assert_apps_detected(rule_runner, constraints1="CPython==3.9.*")
 
 
-@skip_unless_all_pythons_present(PY_27, PY_39)
+@skip_unless_all_pythons_present(PY_38, PY_39)
 def test_partitioning_by_ics(rule_runner: RuleRunner) -> None:
-    assert_apps_detected(rule_runner, constraints1="CPython==3.9.*", constraints2="CPython==2.7.*")
+    assert_apps_detected(rule_runner, constraints1="CPython==3.8.*", constraints2="CPython==3.9.*")