Add compatibility date for Pyodide 0.27.1

Author: hoodmane

src/workerd/io/compatibility-date.capnp

@@ -679,4 +679,11 @@ struct CompatibilityFlags @0x8f8c1b68151b6cef {
       $compatDisableFlag("cache_no_cache_disabled")
       $experimental;
   # Enables the use of cache: no-cache in the fetch api.
+
+  pythonWorkers20250116 @71 :Bool
+      $compatEnableFlag("python_workers_20250116")
+      $experimental
+      $pythonSnapshotRelease(pyodide = "0.27.1", pyodideRevision = "2025-01-16",
+          packages = "2024-12-18", backport = 1,
+          baselineSnapshotHash = "TODO");
 }

src/workerd/server/tests/python/BUILD.bazel

@@ -38,4 +38,11 @@ py_wd_test(
     ],
 )
 
-gen_import_tests(PYODIDE_IMPORTS_TO_TEST)
+gen_import_tests(
+    PYODIDE_IMPORTS_TO_TEST,
+    # TODO: Micropip version mismatch for 0.27.0
+    pkg_python_versions = {"micropip": [
+        "0.26.0a2",
+        "development",
+    ]},
+)

src/workerd/server/tests/python/import_tests.bzl

@@ -32,7 +32,7 @@ def generate_wd_test_file(requirement):
     return WD_FILE_TEMPLATE.format(requirement, requirement)
 
 # to_test is a dictionary from library name to list of imports
-def gen_import_tests(to_test):
+def gen_import_tests(to_test, pkg_python_versions = {}):
     for lib in to_test.keys():
         prefix = "import/" + lib
         worker_py_fname = prefix + "/worker.py"
@@ -52,6 +52,7 @@ def gen_import_tests(to_test):
             name = prefix,
             directory = lib,
             src = wd_test_fname,
+            python_flags = pkg_python_versions.get(lib, "all"),
             args = ["--experimental", "--pyodide-package-disk-cache-dir", "../all_pyodide_wheels"],
             data = [worker_py_fname, "@all_pyodide_wheels//:whls"],
             size = "enormous",

src/workerd/server/tests/python/py_wd_test.bzl

@@ -2,7 +2,8 @@ load("@bazel_skylib//rules:expand_template.bzl", "expand_template")
 load("//:build/wd_test.bzl", "wd_test")
 
 FEATURE_FLAGS = {
-    "0.26.0a2": ["python_workers"],
+    "0.26.0a2": [],
+    "0.27.0": ["python_workers_20250116"],
     "development": ["python_workers_development", "python_external_packages"],
 }
 
@@ -37,7 +38,8 @@ def py_wd_test(
         name_flag = name + "_" + python_flag
         templated_src = name_flag.replace("/", "-") + "@template"
         templated_src = "/".join(src.split("/")[:-1] + [templated_src])
-        feature_flags_txt = ",".join(['"{}"'.format(flag) for flag in FEATURE_FLAGS[python_flag]])
+        flags = FEATURE_FLAGS[python_flag] + ["python_workers"]
+        feature_flags_txt = ",".join(['"{}"'.format(flag) for flag in flags])
         expand_template(
             name = name_flag + "@rule",
             out = templated_src,