mraa mock: Add SPI functionality

Signed-off-by: Alex Tereschenko <alext.mkrs@gmail.com>
Signed-off-by: Brendan Le Foll <brendan.le.foll@intel.com>

tests/mock/spi_checks_write_byte.py

@@ -0,0 +1,52 @@
+#!/usr/bin/env python
+
+# Author: Alex Tereschenko <alext.mkrs@gmail.com>
+# Copyright (c) 2016 Alex Tereschenko.
+#
+# Permission is hereby granted, free of charge, to any person obtaining
+# a copy of this software and associated documentation files (the
+# "Software"), to deal in the Software without restriction, including
+# without limitation the rights to use, copy, modify, merge, publish,
+# distribute, sublicense, and/or sell copies of the Software, and to
+# permit persons to whom the Software is furnished to do so, subject to
+# the following conditions:
+#
+# The above copyright notice and this permission notice shall be
+# included in all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+import mraa as m
+import unittest as u
+
+from spi_checks_shared import *
+
+class SpiChecksWriteByte(u.TestCase):
+  def setUp(self):
+    self.spi = m.Spi(MRAA_SPI_BUS_NUM)
+
+  def tearDown(self):
+    del self.spi
+
+  def test_spi_write_byte(self):
+    TEST_BYTE = 0xEE
+    self.assertEqual(self.spi.writeByte(TEST_BYTE),
+                     TEST_BYTE ^ MOCK_SPI_REPLY_DATA_MODIFIER_BYTE,
+                     "SPI writeByte() returned unexpected data")
+
+  def test_spi_write_byte_invalid_bigger_than_max(self):
+    TEST_VALUE = 0xEEFF
+    self.assertRaises(OverflowError, self.spi.writeByte, TEST_VALUE)
+
+  def test_spi_write_byte_invalid_smaller_than_min(self):
+    TEST_VALUE = -1
+    self.assertRaises(OverflowError, self.spi.writeByte, TEST_VALUE)
+
+if __name__ == "__main__":
+  u.main()