tests: Add infrastructure to run Python unit tests

- Add UHD_ADD_PYTEST() CMake macro
- Add CMake code to tests/CMakeLists.txt to auto-run all registered
  Python unit tests
- Add a token unit test (it replicates parts of ranges_test.cpp)

The way Python-based unit tests are implemented in UHD is that they can
import uhd, and then operate on the module as usual.

Writing unit tests in Python instead of C++ can have multiple
advantages:
- If they test PyBind-wrapped C++ code, they can test both the binding
  and the underlying C++ code at once
- Writing unit tests in Python may be more concise

1 files changed, 20 insertions, 0 deletions

diff --git a/host/tests/pyranges_test.py b/host/tests/pyranges_test.py
new file mode 100644
index 000000000..17137e9f2
--- /dev/null
+++ b/host/tests/pyranges_test.py
@@ -0,0 +1,20 @@
+#
+# Copyright 2020 Ettus Research, a National Instruments Brand
+#
+# SPDX-License-Identifier: GPL-3.0-or-later
+#
+"""
+Unit test for uhd.types.*Range
+"""
+
+import unittest
+import uhd
+
+class RangesTest(unittest.TestCase):
+    """ Test Python-wrapped ranges classes """
+    def test_meta_range(self):
+        """ Test MetaRange.clip() """
+        my_range = uhd.types.MetaRange(1.0, 10.0, 0.5)
+        self.assertEqual(my_range.clip(5.0), 5.0)
+        self.assertEqual(my_range.clip(11.0), 10.0)
+        self.assertEqual(my_range.clip(5.1, True), 5.0)