Snippet to generate tests from numpy for xtensor

make_tests.py

import numpy as np

dtype_map = {
	'bool': 'bool',
	'float32': 'float',
	'float64': 'double',
	'int32': 'int',
	'int64': 'long',
	'uint32': 'unsigned int',
	'uint64': 'unsigned long',
	'complex64': 'std::complex<float>',
	'complex128': 'std::complex<double>',
}
USE_XTENSOR = False

def get_xtype(arr):
	if USE_XTENSOR:
		s = "xtensor<" + dtype_map[str(arr.dtype)] + ", " + str(arr.ndim) + ">"
	else:
		s = "xarray<" + dtype_map[str(arr.dtype)] + ">"
	return s

def get_cpp_initlist(arr, name):
	s = np.array_str(arr)
	s = s.replace('[', '{')
	s = s.replace(']', '}')
	s = s.replace('j', 'i')
	s += ';'
	s = s.replace("\n", "\n" + " " * (len(name) + 3))
	s = name + " = " + s
	return s

def make_test(fn, xt_fn, *args):
	i = 0
	names = []
	res_str = ""
	for arg in args:
		n = PREF + "arg_" + str(i)
		names.append(n)
		s = get_cpp_initlist(arg, "xarray<double> " + n)
		res_str += s + '\n'
		i += 1

	res = fn(*args)
	xt_fn_str = "auto " + PREF + "res = " + xt_fn + '(' + ', '.join(names) + ');\n'
	res_str += xt_fn_str
	if isinstance(res, tuple):
		i = 0
		for el in res:
			n = get_xtype(el) + " " + PREF + "expected_" + str(i)
			s = get_cpp_initlist(el, n) + '\n'
			res_str += s
			i += 1
	else:
		s = get_xtype(res) + " " + get_cpp_initlist(res, PREF + "expected") + '\n'
		res_str += s

	gtest = "EXPECT_TRUE(all(isclose(" + PREF + "res - " + PREF + "expected)));\n"
	res_str += gtest

	print(res_str)


if __name__ == '__main__':
	global PREF
	PREF = ""
	make_test(np.dot, "xt::dot", np.random.rand(5,), np.random.rand(5))
	PREF = "cross"
	make_test(np.cross, "xt::cross", np.random.rand(2,), np.random.rand(3,))
	global USE_XTENSOR
	USE_XTENSOR = True
	PREF = "eig_"
	make_test(np.linalg.eig, "xt::linalg::eig", np.random.rand(5, 5))