Make all tests work on Windows (#32)

(DIS-2009)

dissect/util/ts.py

@@ -1,9 +1,9 @@
 import struct
+import sys
 from datetime import datetime, timedelta, timezone, tzinfo
-from platform import system
 from typing import Dict
 
-if system().lower() in ("windows", "emscripten"):
+if sys.platform in ("win32", "emscripten"):
  _EPOCH = datetime(1970, 1, 1, tzinfo=timezone.utc)
 
  def _calculate_timestamp(ts: float) -> datetime:

tests/test_ts.py

@@ -1,5 +1,5 @@
 import platform
-from datetime import datetime, timezone
+from datetime import datetime, timedelta, timezone
 from importlib import reload
 from unittest.mock import patch
 
@@ -21,10 +21,14 @@ def ts():
  yield reload(ts)
 
 
-@pytest.mark.skipif(platform.system() == "Windows", reason="Time Calculation error. Needs to be fixed.")
 def test_now(ts):
- assert ts.now() < datetime.now(timezone.utc)
- assert ts.now().tzinfo == timezone.utc
+ ts_now = ts.now()
+ datetime_now = datetime.now(timezone.utc)
+ time_diff = datetime_now - ts_now
+
+ # Should be no difference, so only set microseconds equal to remove processing time difference
+ assert timedelta(microseconds=time_diff.microseconds) == time_diff
+ assert ts_now.tzinfo == timezone.utc
 
 
 def test_unix_now(imported_ts):
@@ -111,7 +115,6 @@ def test_wintimestamp(imported_ts):
  )
 
 
-@pytest.mark.skipif(platform.system() == "Windows", reason="Time Calculation error. Needs to be fixed.")
 def test_oatimestamp(imported_ts):
  dt = datetime(2016, 10, 17, 4, 6, 38, 362003, tzinfo=timezone.utc)
  assert imported_ts.oatimestamp(42660.171277338) == dt
@@ -130,7 +133,6 @@ def test_cocoatimestamp(imported_ts):
  assert imported_ts.cocoatimestamp(622894123.221783) == datetime(2020, 9, 27, 10, 8, 43, 221783, tzinfo=timezone.utc)
 
 
-@pytest.mark.skipif(platform.system() == "Windows", reason="Time Calculation error. Needs to be fixed.")
 def test_negative_timestamps(imported_ts):
  # -5000.0 converted to a int representation
  assert imported_ts.oatimestamp(13885591609694748672) == datetime(1886, 4, 22, 0, 0, tzinfo=timezone.utc)