Level up tests, fix bugs and quirks

library/inky/inky.py

@@ -1,5 +1,4 @@
 """Inky e-Ink Display Driver."""
-import sys
 import time
 import struct
 
@@ -8,7 +7,7 @@
 try:
     import numpy
 except ImportError:
-    sys.exit('This library requires the numpy module\nInstall with: sudo apt install python-numpy')
+    raise ImportError('This library requires the numpy module\nInstall with: sudo apt install python-numpy')
 
 WHITE = 0
 BLACK = 1
@@ -204,7 +203,7 @@ def setup(self):
                     import RPi.GPIO as GPIO
                     self._gpio = GPIO
                 except ImportError:
-                    sys.exit('This library requires the RPi.GPIO module\nInstall with: sudo apt install python-rpi.gpio')
+                    raise ImportError('This library requires the RPi.GPIO module\nInstall with: sudo apt install python-rpi.gpio')
             self._gpio.setmode(self._gpio.BCM)
             self._gpio.setwarnings(False)
             self._gpio.setup(self.dc_pin, self._gpio.OUT, initial=self._gpio.LOW, pull_up_down=self._gpio.PUD_OFF)

library/inky/mock.py

@@ -1,11 +1,12 @@
-import sys
+"""PIL/Tkinter based simulator for InkyWHAT and InkyWHAT."""
 import numpy
 
 
 from . import inky
 
 
 class InkyMock(inky.Inky):
+    """Base simulator class for Inky."""
 
     def __init__(self, colour, h_flip=False, v_flip=False):
         """Initialise an Inky pHAT Display.
@@ -17,9 +18,13 @@ def __init__(self, colour, h_flip=False, v_flip=False):
 
         try:
             import tkinter
+        except ImportError:
+            raise ImportError('Simulation requires tkinter')
+
+        try:
             from PIL import ImageTk, Image
         except ImportError:
-            sys.exit('Simulation requires tkinter')
+            raise ImportError('Simulation requires PIL ImageTk and Image')
 
         resolution = (self.WIDTH, self.HEIGHT)
 
@@ -30,6 +35,8 @@ def __init__(self, colour, h_flip=False, v_flip=False):
         self.width, self.height = resolution
         self.cols, self.rows, self.rotation = inky._RESOLUTION[resolution]
 
+        self.buf = numpy.zeros((self.height, self.width), dtype=numpy.uint8)
+
         if colour not in ('red', 'black', 'yellow'):
             raise ValueError('Colour {} is not supported!'.format(colour))
 
@@ -51,19 +58,20 @@ def __init__(self, colour, h_flip=False, v_flip=False):
         # yellow color value: screen capture from
         # https://www.thoughtsmakethings.com/Pimoroni-Inky-pHAT
 
-        self.c_palette = {"black": bw_inky_palette,
-                          "red": red_inky_palette,
-                          "yellow": ylw_inky_palette}
+        self.c_palette = {'black': bw_inky_palette,
+                          'red': red_inky_palette,
+                          'yellow': ylw_inky_palette}
 
         self.tk_root = tkinter.Tk()
-        self.tk_root.title("Inky Preview")
+        self.tk_root.title('Inky Preview')
         self.tk_root.geometry('{}x{}'.format(self.WIDTH, self.HEIGHT))
         self.tk_root.aspect(self.WIDTH, self.HEIGHT, self.WIDTH, self.HEIGHT)
         self.cv = None
         self.cvh = self.HEIGHT
         self.cvw = self.WIDTH
 
     def resize(self, event):
+        """Resize background image to window size."""
         # adapted from:
         # https://stackoverflow.com/questions/24061099/tkinter-resize-background-image-to-window-size
         # https://stackoverflow.com/questions/19838972/how-to-update-an-image-on-a-canvas
@@ -82,7 +90,7 @@ def _simulate(self, region):
         pass
 
     def _display(self, region):
-        im = Image.fromarray(region, "P")
+        im = Image.fromarray(region, 'P')
         im.putpalette(self.c_palette[self.colour])
 
         self.disp_img_copy = im.copy()  # can be changed due to window resizing, so copy
@@ -101,7 +109,7 @@ def show(self, busy_wait=True):
         :param busy_wait: Ignored. Updates are simulated and instant.
 
         """
-        print(">> Simulating {} {}x{}...".format(self.colour, self.WIDTH, self.HEIGHT))
+        print('>> Simulating {} {}x{}...'.format(self.colour, self.WIDTH, self.HEIGHT))
 
         region = self.buf
 
@@ -118,8 +126,7 @@ def show(self, busy_wait=True):
 
 
 class InkyMockPHAT(InkyMock):
-
-    """Inky wHAT e-Ink Display Driver."""
+    """Inky wHAT e-Ink Display Simulator."""
 
     WIDTH = 212
     HEIGHT = 104
@@ -137,8 +144,7 @@ def _simulate(self, region):
 
 
 class InkyMockWHAT(InkyMock):
-
-    """Inky wHAT e-Ink Display Driver."""
+    """Inky wHAT e-Ink Display Simulator."""
 
     WIDTH = 400
     HEIGHT = 300

library/tests/conftest.py

@@ -0,0 +1,60 @@
+"""Test configuration.
+
+These allow the mocking of various Python modules
+that might otherwise have runtime side-effects.
+
+"""
+import sys
+import mock
+import pytest
+
+from tools import MockSMBus
+
+
+@pytest.fixture(scope='function', autouse=False)
+def GPIO():
+    """Mock RPi.GPIO module."""
+    GPIO = mock.MagicMock()
+    # Fudge for Python < 37 (possibly earlier)
+    sys.modules['RPi'] = mock.MagicMock()
+    sys.modules['RPi'].GPIO = GPIO
+    sys.modules['RPi.GPIO'] = GPIO
+    yield GPIO
+    del sys.modules['RPi']
+    del sys.modules['RPi.GPIO']
+
+
+@pytest.fixture(scope='function', autouse=False)
+def smbus2():
+    """Mock smbus2 module."""
+    sys.modules['smbus2'] = mock.Mock()
+    sys.modules['smbus2'].SMBus = MockSMBus
+    yield MockSMBus
+    del sys.modules['smbus2']
+
+
+@pytest.fixture(scope='function', autouse=False)
+def spidev():
+    """Mock spidev module."""
+    spidev = mock.MagicMock()
+    sys.modules['spidev'] = spidev
+    yield spidev
+    del sys.modules['spidev']
+
+
+@pytest.fixture(scope='function', autouse=False)
+def tkinter():
+    """Mock tkinter module."""
+    tkinter = mock.MagicMock()
+    sys.modules['tkinter'] = tkinter
+    yield tkinter
+    del sys.modules['tkinter']
+
+
+@pytest.fixture(scope='function', autouse=False)
+def PIL():
+    """Mock PIL module."""
+    PIL = mock.MagicMock()
+    sys.modules['PIL'] = PIL
+    yield PIL
+    del sys.modules['PIL']

library/tests/test_init.py

@@ -1,67 +1,59 @@
 """Initialization tests for Inky."""
 import sys
 import mock
-from tools import MockSMBus
 
 
-def mockery():
-    """Mock requires modules."""
-    sys.modules['RPi'] = mock.Mock()
-    sys.modules['RPi.GPIO'] = mock.Mock()
-    sys.modules['spidev'] = mock.Mock()
-    sys.modules['smbus2'] = mock.Mock()
-    sys.modules['smbus2'].SMBus = MockSMBus
+def test_init_mock_phat_black(tkinter, PIL):
+    """Test initialisation of InkyMockPHAT with 'black' colour choice."""
+    from inky import InkyMockPHAT
 
+    InkyMockPHAT('black')
 
-def test_init_phat_black():
-    """Test initialisation of InkyPHAT with 'black' colour choice."""
-    mockery()
 
+def test_init_mock_what_black(tkinter, PIL):
+    """Test initialisation of InkyMockWHAT with 'black' colour choice."""
+    from inky import InkyMockWHAT
+
+    InkyMockWHAT('black')
+
+
+def test_init_phat_black(spidev, smbus2):
+    """Test initialisation of InkyPHAT with 'black' colour choice."""
     from inky import InkyPHAT
 
     InkyPHAT('black')
 
 
-def test_init_phat_red():
+def test_init_phat_red(spidev, smbus2):
     """Test initialisation of InkyPHAT with 'red' colour choice."""
-    mockery()
-
     from inky import InkyPHAT
 
     InkyPHAT('red')
 
 
-def test_init_phat_yellow():
+def test_init_phat_yellow(spidev, smbus2):
     """Test initialisation of InkyPHAT with 'yellow' colour choice."""
-    mockery()
-
     from inky import InkyPHAT
 
     InkyPHAT('red')
 
 
-def test_init_what_black():
+def test_init_what_black(spidev, smbus2):
     """Test initialisation of InkyWHAT with 'black' colour choice."""
-    mockery()
-
     from inky import InkyWHAT
 
     InkyWHAT('black')
 
 
-def test_init_what_red():
+def test_init_what_red(spidev, smbus2):
     """Test initialisation of InkyWHAT with 'red' colour choice."""
-    mockery()
-
     from inky import InkyWHAT
 
     InkyWHAT('red')
 
 
-def test_init_what_yellow():
+def test_init_what_yellow(spidev, smbus2):
     """Test initialisation of InkyWHAT with 'yellow' colour choice."""
-    mockery()
-
     from inky import InkyWHAT
 
     InkyWHAT('red')

library/tests/test_install_helpers.py

@@ -0,0 +1,42 @@
+"""Install helper tests for Inky.
+
+These validate that, in case of a missing package, an ImportError is raised.
+
+They don't actually validate that our special message is produced!
+
+"""
+import sys
+import mock
+import pytest
+
+
+def test_mock_phat_no_tkinter():
+    """Test initialisation of InkyMockPHAT without tkinter."""
+    from inky import InkyMockPHAT
+
+    with pytest.raises(ImportError):
+        InkyMockPHAT('black')
+
+
+def test_mock_what_no_tkinter():
+    """Test initialisation of InkyMockWHAT without tkinter."""
+    from inky import InkyMockWHAT
+
+    with pytest.raises(ImportError):
+        InkyMockWHAT('black')
+
+
+def test_mock_phat_no_pil(tkinter):
+    """Test initialisation of InkyMockPHAT without PIL."""
+    from inky import InkyMockPHAT
+
+    with pytest.raises(ImportError):
+        InkyMockPHAT('black')
+
+
+def test_mock_what_no_pil(tkinter):
+    """Test initialisation of InkyMockWHAT without PIL."""
+    from inky import InkyMockWHAT
+
+    with pytest.raises(ImportError):
+        InkyMockWHAT('black')

library/tests/test_simulator.py

@@ -0,0 +1,56 @@
+"""Install helper tests for Inky.
+
+These validate that, in case of a missing package, an ImportError is raised.
+
+They don't actually validate that our special message is produced!
+
+"""
+import sys
+import mock
+import pytest
+from inky.mock import InkyMock, InkyMockPHAT, InkyMockWHAT
+
+
+class InkyMockFAIL(InkyMock):
+    """Inky wHAT e-Ink Display Simulator."""
+
+    WIDTH = 999
+    HEIGHT = 999
+
+    WHITE = 0
+    BLACK = 1
+    RED = 2
+    YELLOW = 2
+
+    def _simulate(self, region):
+        pass
+
+
+def test_mock_invalid_size(tkinter, PIL):
+    """Test a class with an invalid size raises a ValueError."""
+    with pytest.raises(ValueError):
+        InkyMockFAIL('black')
+
+
+def test_mock_invalid_colour(tkinter, PIL):
+    """Test that instantiating with an invalid colour raises a ValueError."""
+    with pytest.raises(ValueError):
+        InkyMockPHAT('octarine')
+
+
+def test_mock_show_phat(tkinter, PIL):
+    """Test that show doesn't explode."""
+    inky = InkyMockPHAT('red')
+    inky.show()
+
+
+def test_mock_show_what(tkinter, PIL):
+    """Test that show doesn't explode."""
+    inky = InkyMockWHAT('red')
+    inky.show()
+
+
+def test_mock_show_180(tkinter, PIL):
+    """Test that show doesn't explode."""
+    inky = InkyMockPHAT('red', h_flip=True, v_flip=True)
+    inky.show()

library/tox.ini

@@ -6,7 +6,7 @@ skip_missing_interpreters = True
 commands =
 	python setup.py develop --no-deps
 	coverage run -m py.test -v -r wsx
-	coverage report
+	coverage report -m
 deps =
 	mock
 	pytest>=3.1