Add first unit tests

Author: florisla

MANIFEST.in

@@ -4,3 +4,4 @@ include *.toml
 include LICENSE
 include .pylintrc
 include noxfile.py
+recursive-include tests *.py

setup.cfg

@@ -24,4 +24,7 @@ ignore =
 	C812,       # Missing trailing comma
 	E203,       # Whitespace before ':'
 	D102,       # Missing docstring in public method
+per-file-ignores =
+    # Missing docstring in public function
+	tests/*:D103,
 

stm32loader/bootloader.py

@@ -249,6 +249,8 @@ def go(self, address):
 
     def write_memory(self, address, data):
         nr_of_bytes = len(data)
+        if nr_of_bytes == 0:
+            return
         assert nr_of_bytes <= 256
 
         if not self.command(self.Command.WRITE_MEMORY):

tests/test_bootloader.py

@@ -0,0 +1,55 @@
+
+from stm32loader.bootloader import Stm32Bootloader
+
+import pytest
+
+try:
+    from unittest.mock import MagicMock
+except ImportError:
+    # Python version <= 3.2
+    from mock import MagicMock
+
+
+@pytest.fixture
+def connection():
+    connection = MagicMock()
+    connection.read.return_value = [Stm32Bootloader.Reply.ACK]
+    return connection
+
+
+@pytest.fixture
+def write(connection):
+    def write_called_with_data(data):
+        data_call = (bytearray(data), )
+        return 1 == sum(args[0] == data_call for args in connection.write.call_args_list)
+    connection.write.called_with_data = write_called_with_data
+    return connection.write
+
+
+@pytest.fixture
+def bootloader(connection):
+    return Stm32Bootloader(connection)
+
+
+def test_constructor_with_connection_None_passes():
+    Stm32Bootloader(connection=None)
+
+
+def test_constructor_does_not_use_connection_directly(connection):
+    Stm32Bootloader(connection)
+    assert not connection.method_calls
+
+
+def test_write_memory_with_zero_bytes_does_not_send_anything(bootloader, connection):
+    bootloader.write_memory(0, b'')
+    assert not connection.method_calls
+
+
+def test_write_memory_with_single_byte_sends_four_data_bytes_padded_with_0xff(bootloader, write):
+    bootloader.write_memory(0, b'1')
+    assert write.called_with_data(b'1\xff\xff\xff')
+
+
+def test_encode_address_returns_correct_bytes_with_checksum():
+    encoded_address = Stm32Bootloader._encode_address(0x04030201)
+    assert bytes(encoded_address) == b'\x04\x03\x02\x01\x04'