python · vstinner · May 16, 2020 · May 4, 2020 · pganssle · May 12, 2020
diff --git a/.github/workflows/coverage.yml b/.github/workflows/coverage.yml
@@ -48,6 +48,7 @@ jobs:
         ./python -m venv .venv
         source ./.venv/bin/activate
         python -m pip install -U coverage
+        python -m pip install -r Misc/requirements-test.txt
         python -m test.pythoninfo
     - name: 'Tests with coverage'
       run: >

diff --git a/.travis.yml b/.travis.yml
@@ -87,6 +87,7 @@ matrix:
         # Need a venv that can parse covered code.
         - ./python -m venv venv
         - ./venv/bin/python -m pip install -U coverage
+        - ./venv/bin/python -m pip install -r Misc/requirements-test.txt
         - ./venv/bin/python -m test.pythoninfo
       script:
         # Skip tests that re-run the entire test suite.

diff --git a/Lib/sysconfig.py b/Lib/sysconfig.py
@@ -546,6 +546,7 @@ def get_config_vars(*args):
 
         if os.name == 'nt':
             _init_non_posix(_CONFIG_VARS)
+            _CONFIG_VARS['TZPATH'] = ''
         if os.name == 'posix':
             _init_posix(_CONFIG_VARS)
         # For backward compatibility, see issue19555

diff --git a/Lib/test/test_zoneinfo/__init__.py b/Lib/test/test_zoneinfo/__init__.py
@@ -0,0 +1 @@
+from .test_zoneinfo import *
diff --git a/Lib/test/test_zoneinfo/__main__.py b/Lib/test/test_zoneinfo/__main__.py
@@ -0,0 +1,3 @@
+import unittest
+
+unittest.main('test.test_zoneinfo')
diff --git a/Lib/test/test_zoneinfo/_support.py b/Lib/test/test_zoneinfo/_support.py
@@ -0,0 +1,76 @@
+import contextlib
+import functools
+import sys
+import threading
+import unittest
+from test.support import import_fresh_module
+
+OS_ENV_LOCK = threading.Lock()
+TZPATH_LOCK = threading.Lock()
+TZPATH_TEST_LOCK = threading.Lock()
+
+
+def call_once(f):
+    """Decorator that ensures a function is only ever called once."""
+    lock = threading.Lock()
+    cached = functools.lru_cache(None)(f)
+
+    @functools.wraps(f)
+    def inner():
+        with lock:
+            return cached()
+
+    return inner
+
+
+@call_once
+def get_modules():
+    """Retrieve two copies of zoneinfo: pure Python and C accelerated.
+
+    Because this function manipulates the import system in a way that might
+    be fragile or do unexpected things if it is run many times, it uses a
+    `call_once` decorator to ensure that this is only ever called exactly
+    one time — in other words, when using this function you will only ever
+    get one copy of each module rather than a fresh import each time.
+    """
+    import zoneinfo as c_module
+
+    py_module = import_fresh_module("zoneinfo", blocked=["_zoneinfo"])
+
+    return py_module, c_module
+
+
+@contextlib.contextmanager
+def set_zoneinfo_module(module):
+    """Make sure sys.modules["zoneinfo"] refers to `module`.
+
+    This is necessary because `pickle` will refuse to serialize
+    an type calling itself `zoneinfo.ZoneInfo` unless `zoneinfo.ZoneInfo`
+    refers to the same object.
+    """
+
+    NOT_PRESENT = object()
+    old_zoneinfo = sys.modules.get("zoneinfo", NOT_PRESENT)
+    sys.modules["zoneinfo"] = module
+    yield
+    if old_zoneinfo is not NOT_PRESENT:
+        sys.modules["zoneinfo"] = old_zoneinfo
+    else:  # pragma: nocover
+        sys.modules.pop("zoneinfo")
+
+
+class ZoneInfoTestBase(unittest.TestCase):
+    @classmethod
+    def setUpClass(cls):
+        cls.klass = cls.module.ZoneInfo
+        super().setUpClass()
+
+    @contextlib.contextmanager
+    def tzpath_context(self, tzpath, lock=TZPATH_LOCK):
+        with lock:
+            old_path = self.module.TZPATH
+            try:
+                self.module.reset_tzpath(tzpath)
+                yield
+            finally:
+                self.module.reset_tzpath(old_path)
diff --git a/Lib/test/test_zoneinfo/data/update_test_data.py b/Lib/test/test_zoneinfo/data/update_test_data.py
@@ -0,0 +1,122 @@
+"""
+Script to automatically generate a JSON file containing time zone information.
+
+This is done to allow "pinning" a small subset of the tzdata in the tests,
+since we are testing properties of a file that may be subject to change. For
+example, the behavior in the far future of any given zone is likely to change,
+but "does this give the right answer for this file in 2040" is still an
+important property to test.
+
+This must be run from a computer with zoneinfo data installed.
+"""
+from __future__ import annotations
+
+import base64
+import functools
+import json
+import lzma
+import pathlib
+import textwrap
+import typing
+
+import zoneinfo
+
+KEYS = [
+    "Africa/Abidjan",
+    "Africa/Casablanca",
+    "America/Los_Angeles",
+    "America/Santiago",
+    "Asia/Tokyo",
+    "Australia/Sydney",
+    "Europe/Dublin",
+    "Europe/Lisbon",
+    "Europe/London",
+    "Pacific/Kiritimati",
+    "UTC",
+]
+
+TEST_DATA_LOC = pathlib.Path(__file__).parent
+
+
+@functools.lru_cache(maxsize=None)
+def get_zoneinfo_path() -> pathlib.Path:
+    """Get the first zoneinfo directory on TZPATH containing the "UTC" zone."""
+    key = "UTC"
+    for path in map(pathlib.Path, zoneinfo.TZPATH):
+        if (path / key).exists():
+            return path
+    else:
+        raise OSError("Cannot find time zone data.")
+
+
+def get_zoneinfo_metadata() -> typing.Dict[str, str]:
+    path = get_zoneinfo_path()
+
+    tzdata_zi = path / "tzdata.zi"
+    if not tzdata_zi.exists():
+        # tzdata.zi is necessary to get the version information
+        raise OSError("Time zone data does not include tzdata.zi.")
+
+    with open(tzdata_zi, "r") as f:
+        version_line = next(f)
+
+    _, version = version_line.strip().rsplit(" ", 1)
+
+    if (
+        not version[0:4].isdigit()
+        or len(version) < 5
+        or not version[4:].isalpha()
+    ):
+        raise ValueError(
+            "Version string should be YYYYx, "
+            + "where YYYY is the year and x is a letter; "
+            + f"found: {version}"
+        )
+
+    return {"version": version}
+
+
+def get_zoneinfo(key: str) -> bytes:
+    path = get_zoneinfo_path()
+
+    with open(path / key, "rb") as f:
+        return f.read()
+
+
+def encode_compressed(data: bytes) -> typing.List[str]:
+    compressed_zone = lzma.compress(data)
+    raw = base64.b85encode(compressed_zone)
+
+    raw_data_str = raw.decode("utf-8")
+
+    data_str = textwrap.wrap(raw_data_str, width=70)
+    return data_str
+
+
+def load_compressed_keys() -> typing.Dict[str, typing.List[str]]:
+    output = {key: encode_compressed(get_zoneinfo(key)) for key in KEYS}
+
+    return output
+
+
+def update_test_data(fname: str = "zoneinfo_data.json") -> None:
+    TEST_DATA_LOC.mkdir(exist_ok=True, parents=True)
+
+    # Annotation required: https://github.com/python/mypy/issues/8772
+    json_kwargs: typing.Dict[str, typing.Any] = dict(
+        indent=2, sort_keys=True,
+    )
+
+    compressed_keys = load_compressed_keys()
+    metadata = get_zoneinfo_metadata()
+    output = {
+        "metadata": metadata,
+        "data": compressed_keys,
+    }
+
+    with open(TEST_DATA_LOC / fname, "w") as f:
+        json.dump(output, f, **json_kwargs)
+
+
+if __name__ == "__main__":
+    update_test_data()
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1 @@
		from .test_zoneinfo import *
Copy link Member vstinner May 14, 2020 Choose a reason for hiding this comment The reason will be displayed to describe this comment to others. Learn more. Why not putting test content in this file, as done by test_warnings/init.py for example, rather than having test_zoneinfo/test_zoneinfo.py? Copy link Member Author pganssle May 14, 2020 Choose a reason for hiding this comment The reason will be displayed to describe this comment to others. Learn more. There's a few reasons for this. The most immediate reason is that in the reference implementation there's also a `test_zoneinfo_property.py`, which has all the property tests for this module. Once feature freeze is done, I'm planning to make the case for adding property tests to the standard library, at which point we'll want the parallel structure anyway. Even if that doesn't happen, I'm considering a future modification to the test similar to the way the datetime tests are split between `datetimetester.py` and `test_datetime.py`, and `test_datetime.py` generates C and pure Python tests from just the C tests (as opposed to the way I'm manually doing it now). Copy link Member vstinner May 14, 2020 Choose a reason for hiding this comment The reason will be displayed to describe this comment to others. Learn more. Oh ok. I was more a question than a request. I'm fine with the current file layout.
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1,3 @@
		import unittest

		unittest.main('test.test_zoneinfo')