Remove the skip mark for test_delta_func (#4014)

* recover test_delta_func

Signed-off-by: Jinzhe Zeng <jinzhe.zeng@rutgers.edu>

* pre-commit auto-fixes

* bump scipy for Windows

* add comments to pyproject.toml

* pre-commit auto-fixes

---------

Signed-off-by: Jinzhe Zeng <jinzhe.zeng@rutgers.edu>
Co-authored-by: Janosh Riebesell <janosh.riebesell@gmail.com>

pyproject.toml

@@ -66,6 +66,9 @@ dependencies = [
     "requests>=2.32",
     "ruamel.yaml>=0.17.0",
     "scipy>=1.13.0",
+    # scipy<1.14.1 is incompatible with NumPy 2.0 on Windows
+    # https://github.com/scipy/scipy/issues/21052
+    "scipy>=1.14.1; platform_system == 'Windows'",
     "spglib>=2.5.0",
     "sympy>=1.2",
     "tabulate>=0.9",

tests/io/vasp/test_optics.py

@@ -1,7 +1,5 @@
 from __future__ import annotations
 
-import sys
-
 import numpy as np
 import pytest
 import scipy.special
@@ -53,10 +51,6 @@ def test_optics(self):
         assert len(x_val) == len(y_val) == len(text)
 
 
-@pytest.mark.skipif(
-    sys.platform == "win32" and int(np.__version__[0]) >= 2,
-    reason="Fails on Windows with numpy > 2.0.0, awaiting https://github.com/scipy/scipy/issues/21052 resolution",
-)
 def test_delta_func():
     x = np.array([0, 1, 2, 3, 4, 5])