# coding=utf-8

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import unittest
from parameterized import parameterized
import math
import torch


class TestCacheConsistency(unittest.TestCase):

    def test_consistency(self, verbose=False):
        """
        Test that cached values are not modified externally.
        
        This test verifies that the LRU cache decorator properly handles
        deep copying to prevent unintended modifications to cached objects.
        
        Parameters
        -----------
        verbose : bool, optional
            Whether to print verbose output, by default False
        """
        if verbose:
            print("Testing that cache values does not get modified externally")
        from torch_harmonics.legendre import _precompute_legpoly

        with torch.no_grad():
            cost = torch.cos(torch.linspace(0.0, 2.0 * math.pi, 10, dtype=torch.float64))
            leg1 = _precompute_legpoly(10, 10, cost)
            # perform in-place modification of leg1
            leg1 *= -1.0
            leg2 = _precompute_legpoly(10, 10, cost)
            self.assertFalse(torch.allclose(leg1, leg2))


if __name__ == "__main__":
    unittest.main()