Update dateutil 2.8.1 (43b7838) → 2.8.1 (c496b4f).

CHANGES.md

@@ -2,6 +2,7 @@
 
 * Update attr 20.1.0.dev0 (4bd6827) to 20.2.0 (4f74fba)
 * Update Beautiful Soup 4.8.2 (r559) to 4.9.1 (r585)
+* Update dateutil 2.8.1 (43b7838) to 2.8.1 (c496b4f)
 * Change add diskcache_py3 5.0.1 (9670fbb)
 * Change add diskcache_py2 4.1.0 (b0451e0)
 * Update feedparser_py3 6.0.0b3 (7e255f0) to 6.0.1 (98d189fa)

lib/dateutil/zoneinfo/rebuild.py

@@ -3,7 +3,7 @@ import os
 import tempfile
 import shutil
 import json
-from subprocess import check_call
+from subprocess import check_call, check_output
 from tarfile import TarFile
 
 from dateutil.zoneinfo import METADATA_FN, ZONEFILENAME
@@ -23,11 +23,9 @@ def rebuild(filename, tag=None, format="gz", zonegroups=[], metadata=None):
             for name in zonegroups:
                 tf.extract(name, tmpdir)
             filepaths = [os.path.join(tmpdir, n) for n in zonegroups]
-            try:
-                check_call(["zic", "-d", zonedir] + filepaths)
-            except OSError as e:
-                _print_on_nosuchfile(e)
-                raise
+
+            _run_zic(zonedir, filepaths)
+
         # write metadata file
         with open(os.path.join(zonedir, METADATA_FN), 'w') as f:
             json.dump(metadata, f, indent=4, sort_keys=True)
@@ -40,6 +38,30 @@ def rebuild(filename, tag=None, format="gz", zonegroups=[], metadata=None):
         shutil.rmtree(tmpdir)
 
 
+def _run_zic(zonedir, filepaths):
+    """Calls the ``zic`` compiler in a compatible way to get a "fat" binary.
+
+    Recent versions of ``zic`` default to ``-b slim``, while older versions
+    don't even have the ``-b`` option (but default to "fat" binaries). The
+    current version of dateutil does not support Version 2+ TZif files, which
+    causes problems when used in conjunction with "slim" binaries, so this
+    function is used to ensure that we always get a "fat" binary.
+    """
+
+    try:
+        help_text = check_output(["zic", "--help"])
+    except OSError as e:
+        _print_on_nosuchfile(e)
+        raise
+
+    if b"-b " in help_text:
+        bloat_args = ["-b", "fat"]
+    else:
+        bloat_args = []
+
+    check_call(["zic"] + bloat_args + ["-d", zonedir] + filepaths)
+
+
 def _print_on_nosuchfile(e):
     """Print helpful troubleshooting message