Update min python version to 3.10 (#25891)

This also involved updating the base linux image on which we run our
tests from
Ubuntu/Focal 20.04 to Ubuntu/Jammy 22.04.

This gives us access to match/case constructs, as well as for other nice
things like `str.removeprefix`, and `BooleanOptionalArgument`.

Author: sbc100

.circleci/config.yml

@@ -13,9 +13,9 @@ executors:
       - image: cimg/python:3.10.7
     environment:
       EMCC_CORES: "4"
-  focal:
+  ubuntu-lts:
     docker:
-      - image: emscripten/emscripten-ci:focal
+      - image: emscripten/emscripten-ci:jammy
     environment:
       LANG: "C.UTF-8"
       EMCC_CORES: "4"
@@ -530,7 +530,7 @@ commands:
 
 jobs:
   build-docs:
-    executor: focal
+    executor: ubuntu-lts
     steps:
       - checkout
       - pip-install
@@ -540,21 +540,21 @@ jobs:
       - run: make -C site html
   ruff:
     # Keep in sync with ruff commands in tools/maint/pre-push
-    executor: focal
+    executor: ubuntu-lts
     steps:
       - checkout
       - pip-install
       - run: ruff check
       # TODO (cclauss): When ruff supports rules these errors without --preview, remove following line
       - run: ruff check --preview --select=E20,E30,E221,E225,E226
   vulture:
-    executor: focal
+    executor: ubuntu-lts
     steps:
       - checkout
       - pip-install
       - run: vulture . --min-confidence 100
   mypy:
-    executor: focal
+    executor: ubuntu-lts
     steps:
       - checkout
       - pip-install
@@ -568,13 +568,13 @@ jobs:
           npm run lint
           npm run check
   test-sanity:
-    executor: focal
+    executor: ubuntu-lts
     steps:
       - run-tests-linux:
           frozen_cache: false
           test_targets: "sanity"
   build-linux:
-    executor: focal
+    executor: ubuntu-lts
     # xlarge has 4x the cores of the default medium, costs 4x as much, and runs
     # in about 1/2 the time, so it is not cost-effective (overall it is 2x the
     # cost for the same work), but given this blocks almost all the other jobs
@@ -632,19 +632,19 @@ jobs:
       - persist
   # Perhaps we don't need to run this suite with every commit. Consider moving this to FYI bot.
   test-posixtest:
-    executor: focal
+    executor: ubuntu-lts
     steps:
       - run-tests-linux:
           test_targets: "posixtest"
   test-core0:
-    executor: focal
+    executor: ubuntu-lts
     environment:
       EMTEST_SKIP_NODE_CANARY: "1"
     steps:
       - run-tests-linux:
           test_targets: "core0"
   test-core2:
-    executor: focal
+    executor: ubuntu-lts
     environment:
       EMTEST_BROWSER: "node"
       EMTEST_SKIP_NODE_CANARY: "1"
@@ -692,7 +692,7 @@ jobs:
             corez.test_dylink_syslibs_all"
       - upload-test-results
   test-core3:
-    executor: focal
+    executor: ubuntu-lts
     environment:
       EMTEST_SKIP_NODE_CANARY: "1"
     steps:
@@ -779,14 +779,14 @@ jobs:
             strict.test_dylink_global_inits_reversed
             "
   test-modularize-instance:
-    executor: focal
+    executor: ubuntu-lts
     environment:
       EMTEST_SKIP_NODE_CANARY: "1"
     steps:
       - run-tests-linux:
           test_targets: "instance"
   test-stress:
-    executor: focal
+    executor: ubuntu-lts
     environment:
       EMTEST_SKIP_NODE_CANARY: "1"
     steps:
@@ -810,7 +810,7 @@ jobs:
   test-wasm2js1:
     environment:
       EMTEST_SKIP_NODE_CANARY: "1"
-    executor: focal
+    executor: ubuntu-lts
     steps:
       - run-tests-linux:
           test_targets: "wasm2js1"
@@ -1062,7 +1062,7 @@ jobs:
             "
       - upload-test-results
   test-other:
-    executor: focal
+    executor: ubuntu-lts
     environment:
       EMTEST_SKIP_NODE_CANARY: "1"
       EMTEST_SKIP_RUST: "1"
@@ -1076,7 +1076,7 @@ jobs:
           # headers on emsdk-bundled clang
           test_targets: "other jslib skip:other.test_native_link_error_message"
   test-browser-chrome:
-    executor: focal
+    executor: ubuntu-lts
     environment:
       EMTEST_LACKS_WEBGPU: "1"
     steps:
@@ -1101,7 +1101,7 @@ jobs:
             browser.test_audio_worklet*
             "
   test-browser-chrome-wasm64:
-    executor: focal
+    executor: ubuntu-lts
     environment:
       EMTEST_LACKS_WEBGPU: "1"
       EMTEST_VISUALIZE: "1"
@@ -1131,23 +1131,23 @@ jobs:
           name: Check profile
           command: file -E out/graph.html
   test-browser-chrome-2gb:
-    executor: focal
+    executor: ubuntu-lts
     environment:
       EMTEST_LACKS_WEBGPU: "1"
     steps:
       - run-tests-chrome:
           title: "browser_2gb"
           test_targets: "browser_2gb"
   test-browser-chrome-wasm64-4gb:
-    executor: focal
+    executor: ubuntu-lts
     environment:
       EMTEST_LACKS_WEBGPU: "1"
     steps:
       - run-tests-chrome:
           title: "browser64_4gb"
           test_targets: "browser64_4gb"
   test-browser-firefox:
-    executor: focal
+    executor: ubuntu-lts
     environment:
       EMTEST_LACKS_GROWABLE_ARRAYBUFFERS: "1"
     steps:
@@ -1166,7 +1166,7 @@ jobs:
             skip:browser.test_glut_glutget
             "
   test-browser-firefox-wasm64:
-    executor: focal
+    executor: ubuntu-lts
     steps:
       - checkout
       - pip-install
@@ -1218,12 +1218,12 @@ jobs:
   # TODO(sbc): Re-enable once we figure out why the emrun tests are
   # locking up.
   #test-browser-chrome-emrun:
-  #  executor: focal
+  #  executor: ubuntu-lts
   #  steps:
   #    - run-tests-chrome:
   #        test_targets: "emrun"
   test-sockets-chrome:
-    executor: focal
+    executor: ubuntu-lts
     steps:
       - test-sockets-chrome
 

ChangeLog.md

@@ -20,6 +20,8 @@ See docs/process.md for more on how version tagging works.
 
 4.0.22 (in development)
 -----------------------
+- The minimum version of python required to run emscripten was updated from 3.8
+  to 3.10. (#25891)
 
 4.0.21 - 12/02/25
 -----------------

pyproject.toml

@@ -1,5 +1,5 @@
 [project]
-requires-python = ">=3.8"
+requires-python = ">=3.10"
 
 [tool.ruff]
 line-length = 100

test/common.py

@@ -22,7 +22,6 @@
 from functools import wraps
 from pathlib import Path
 from subprocess import PIPE, STDOUT
-from typing import Dict, Tuple
 
 import clang_native
 import jsrun
@@ -1091,7 +1090,7 @@ def assertBinaryEqual(self, file1, file2):
     self.assertEqual(read_binary(file1),
                      read_binary(file2))
 
-  library_cache: Dict[str, Tuple[str, object]] = {}
+  library_cache: dict[str, tuple[str, object]] = {}
 
   def get_build_dir(self):
     ret = self.in_dir('building')

test/other/ports/external.py

@@ -4,7 +4,6 @@
 # found in the LICENSE file.
 
 import os
-from typing import Dict, Optional
 
 URL = 'https://emscripten.org'
 DESCRIPTION = 'Test Description'
@@ -18,7 +17,7 @@
 }
 
 # user options (from --use-port)
-opts: Dict[str, Optional[str]] = {
+opts: dict[str, str | None] = {
   'value1': None,
   'value2': None,
   'value3': "v3",

test/parallel_testsuite.py

@@ -315,7 +315,7 @@ def log_test_run_for_visualization(self, flaky_tests):
       # block, so generate one on the fly.
       dummy_test_task_counter = os.path.getsize(profiler_log_file) if os.path.isfile(profiler_log_file) else 0
       # Remove the redundant 'test_' prefix from each test, since character space is at a premium in the visualized graph.
-      test_name = utils.removeprefix(self.test_short_name(), 'test_')
+      test_name = self.test_short_name().removeprefix('test_')
       with open(profiler_log_file, 'a') as prof:
         prof.write(f',\n{{"pid":{dummy_test_task_counter},"op":"start","time":{self.start_time},"cmdLine":["{test_name}"],"color":"{color}"}}')
         prof.write(f',\n{{"pid":{dummy_test_task_counter},"op":"exit","time":{self.start_time + self.test_duration},"returncode":0}}')

test/runner.py

@@ -482,9 +482,7 @@ def parse_args():
   parser.add_argument('--verbose', '-v', action='count', default=0,
                       help="Show test stdout and stderr, and don't use the single-line test reporting. "
                            'Specifying `-v` twice will enable test framework logging (i.e. EMTEST_VERBOSE)')
-  # TODO: Replace with BooleanOptionalAction once we can depend on python3.9
-  parser.add_argument('--ansi', action='store_true', default=None)
-  parser.add_argument('--no-ansi', action='store_false', dest='ansi', default=None)
+  parser.add_argument('--ansi', action=argparse.BooleanOptionalAction, default=None)
   parser.add_argument('--all-engines', action='store_true')
   parser.add_argument('--detect-leaks', action='store_true')
   parser.add_argument('--skip-slow', action='store_true', help='Skip tests marked as slow')

test/sockets/socket_relay.py

@@ -18,13 +18,12 @@
 import sys
 import threading
 import time
-from typing import Optional
 
 ports = [int(sys.argv[1]), int(sys.argv[2])]
 
 
 class Listener(threading.Thread):
-  other: Optional[Listener] = None  # noqa: F821
+  other: Listener | None = None  # noqa: F821
 
   def run(self):
     self.conn = None

test/test_benchmark.py

@@ -13,7 +13,6 @@
 import unittest
 import zlib
 from pathlib import Path
-from typing import List
 
 if __name__ == '__main__':
   raise Exception('do not run this file directly; do something like: test/runner.py benchmark')
@@ -137,7 +136,7 @@ def add_stat(name, size, gzip_size):
       size = os.path.getsize(file)
       gzip_size = len(zlib.compress(read_binary(file)))
       if self.record_stats:
-        add_stat(utils.removeprefix(os.path.basename(file), 'size_'), size, gzip_size)
+        add_stat(os.path.basename(file).removeprefix('size_'), size, gzip_size)
       total_size += size
       total_gzip_size += gzip_size
 
@@ -353,7 +352,7 @@ def get_output_files(self):
 
 # Benchmarkers
 
-benchmarkers: List[Benchmarker] = []
+benchmarkers: list[Benchmarker] = []
 
 # avoid the baseline compiler running, because it adds a lot of noise
 # (the nondeterministic time it takes to get to the full compiler ends up

test/test_other.py

@@ -2982,7 +2982,7 @@ def test_extern_prepost(self):
   def test_js_optimizer(self, passes, filename=None):
     if not filename:
       testname = self.id().split('.')[-1]
-      filename = utils.removeprefix(testname, 'test_js_optimizer_') + '.js'
+      filename = testname.removeprefix('test_js_optimizer_') + '.js'
     filename = test_file('js_optimizer', filename)
     expected_file = utils.unsuffixed(filename) + '-output.js'
     # test calling optimizer