docstr: Test edge cases.
docstr_tok: ["Test","edge","cases","."]
code: def test_edge_cases(self, x, xp, scp):
      """
      Test edge cases.
      """
      # Peaks have same height, prominence and bases
      x = xp.asarray(x)
      peaks = xp.asarray([1, 3, 5])
      out = scp.signal.peak_prominences(x, peaks)
      return out
  
imports: import pytest
  import cupy
  from cupy.cuda import driver
  from cupy.cuda import runtime
  from cupy import testing
  import cupyx.scipy.signal
  import numpy
label_desc: Use image node_id 3 for calling the TestPeakProminences obj's underlying member method code with example usage: obj.test_edge_cases(x, xp, scp) and returns: out