CUDA: add numeric conversion tests\n\nAdds kernel-based tests

numba_cuda/numba/cuda/tests/test_conversion.py

@@ -0,0 +1,75 @@
+import numpy as np
+
+from numba import cuda
+from numba.cuda.testing import CUDATestCase, skip_on_cudasim
+
+
+@cuda.jit
+def convert_kernel(inp, out):
+    i = cuda.grid(1)
+    if i < inp.size:
+        out[i] = inp[i]
+
+
+@skip_on_cudasim("Conversion semantics differ under cudasim")
+class TestCudaConversion(CUDATestCase):
+
+    def _launch_1d(self, kernel, args, size):
+        threadsperblock = 128
+        blockspergrid = (size + threadsperblock - 1) // threadsperblock
+        kernel[blockspergrid, threadsperblock](*args)
+        cuda.synchronize()
+
+
+    def _run_conversion(self, src, dst_dtype):
+        out = np.zeros_like(src, dtype=dst_dtype)
+
+        d_src = cuda.to_device(src)
+        d_out = cuda.to_device(out)
+
+        self._launch_1d(convert_kernel, (d_src, d_out), src.size)
+
+        result = d_out.copy_to_host()
+        expected = src.astype(dst_dtype)
+
+        np.testing.assert_array_equal(result, expected)
+
+
+    def test_int_to_float(self):
+        src = np.array([1, -2, 3, 4], dtype=np.int32)
+        self._run_conversion(src, np.float32)
+
+
+    def test_float_to_int_truncation(self):
+        src = np.array([1.7, -2.2, 3.9], dtype=np.float32)
+        self._run_conversion(src, np.int32)
+
+
+    def test_int_to_complex(self):
+        src = np.array([1, -2, 3], dtype=np.int32)
+        self._run_conversion(src, np.complex64)
+
+
+    def test_float_to_complex(self):
+        src = np.array([1.5, -2.25, 3.75], dtype=np.float32)
+        self._run_conversion(src, np.complex64)
+
+
+    def test_bool_to_int(self):
+        src = np.array([True, False, True], dtype=np.bool_)
+        self._run_conversion(src, np.int32)
+
+
+    def test_int_to_bool(self):
+        src = np.array([0, 1, -3, 4], dtype=np.int32)
+        self._run_conversion(src, np.bool_)
+
+
+    def test_bool_to_float(self):
+        src = np.array([True, False, True], dtype=np.bool_)
+        self._run_conversion(src, np.float32)
+
+
+    def test_float_to_bool(self):
+        src = np.array([0.0, 1.2, -0.5], dtype=np.float32)
+        self._run_conversion(src, np.bool_)