Ignore a doctest that uses threads within the file

Author: agriyakhetarpal

numcodecs/zarr3.py

@@ -24,6 +24,19 @@
 
 from __future__ import annotations
 
+# Short workaround for skipping the doctest above in a WASM environment
+# compiled via Emscripten where threads are not available, and accessing
+# the pytest config has no effect and ignoring warnings does not work.
+try:
+    import pytest
+
+    from numcodecs.tests.common import is_wasm
+
+    if is_wasm:
+        pytest.skip("zarr3 doctests not supported in WASM", allow_module_level=True)
+except (ImportError, ModuleNotFoundError):  # not running tests
+    pass
+
 import asyncio
 import math
 from collections.abc import Callable