Merge pull request #28 from pimoroni/tests-and-qa

Tests and QA

examples/compensated-temperature.py

@@ -4,10 +4,6 @@ import time
 import bme680
 from subprocess import PIPE, Popen
 
-try:
-    from smbus2 import SMBus
-except ImportError:
-    from smbus import SMBus
 
 print("""compensated-temperature.py - Use the CPU temperature to compensate temperature
 readings from the BME680 sensor. Method adapted from Initial State's Enviro pHAT
@@ -31,12 +27,14 @@ sensor.set_pressure_oversample(bme680.OS_4X)
 sensor.set_temperature_oversample(bme680.OS_8X)
 sensor.set_filter(bme680.FILTER_SIZE_3)
 
+
 # Gets the CPU temperature in degrees C
 def get_cpu_temperature():
     process = Popen(['vcgencmd', 'measure_temp'], stdout=PIPE)
     output, _error = process.communicate()
     return float(output[output.index('=') + 1:output.rindex("'")])
 
+
 factor = 1.0  # Smaller numbers adjust temp down, vice versa
 smooth_size = 10  # Dampens jitter due to rapid CPU temp changes
 

examples/temperature-offset.py

@@ -22,6 +22,7 @@ sensor.set_pressure_oversample(bme680.OS_4X)
 sensor.set_temperature_oversample(bme680.OS_8X)
 sensor.set_filter(bme680.FILTER_SIZE_3)
 
+
 def display_data(offset=0):
     sensor.set_temp_offset(offset)
     sensor.get_sensor_data()
@@ -32,6 +33,7 @@ def display_data(offset=0):
     print(output)
     print('')
 
+
 print('Initial readings')
 display_data()
 

library/setup.cfg

@@ -12,3 +12,4 @@ ignore =
 	E501
 	F403
 	F405
+	W504

library/tests/conftest.py

@@ -0,0 +1,101 @@
+import sys
+import mock
+import pytest
+import bme680
+from bme680.constants import CalibrationData
+
+
+class MockSMBus:
+    """Mock a basic non-presence SMBus device to cause BME680 to fail.
+
+    Returns 0 in all cases, so that CHIP_ID will never match.
+
+    """
+
+    def __init__(self, bus):  # noqa D107
+        pass
+
+    def read_byte_data(self, addr, register):
+        """Return 0 for all read attempts."""
+        return 0
+
+
+class MockSMBusPresent:
+    """Mock enough of the BME680 for the library to initialise and test."""
+
+    def __init__(self, bus):
+        """Initialise with test data."""
+        self.regs = [0 for _ in range(256)]
+        self.regs[bme680.CHIP_ID_ADDR] = bme680.CHIP_ID
+
+    def read_byte_data(self, addr, register):
+        """Read a single byte from fake registers."""
+        return self.regs[register]
+
+    def write_byte_data(self, addr, register, value):
+        """Write a single byte to fake registers."""
+        self.regs[register] = value
+
+    def read_i2c_block_data(self, addr, register, length):
+        """Read up to length bytes from register."""
+        return self.regs[register:register + length]
+
+
+@pytest.fixture(scope='function', autouse=False)
+def smbus_notpresent():
+    """Mock smbus module."""
+    smbus = mock.MagicMock()
+    smbus.SMBus = MockSMBus
+    sys.modules['smbus'] = smbus
+    yield smbus
+    del sys.modules['smbus']
+
+
+@pytest.fixture(scope='function', autouse=False)
+def smbus():
+    """Mock smbus module."""
+    smbus = mock.MagicMock()
+    smbus.SMBus = MockSMBusPresent
+    sys.modules['smbus'] = smbus
+    yield smbus
+    del sys.modules['smbus']
+
+
+@pytest.fixture(scope='function', autouse=False)
+def calibration():
+    """Mock bme680 calibration."""
+    calibration = CalibrationData()
+    # Dump of calibration data borrowed from:
+    # https://github.com/pimoroni/bme680-python/issues/11
+    data = {
+        'par_gh1': -30,
+        'par_gh2': -24754,
+        'par_gh3': 18,
+        'par_h1': 676,
+        'par_h2': 1029,
+        'par_h3': 0,
+        'par_h4': 45,
+        'par_h5': 20,
+        'par_h6': 120,
+        'par_h7': -100,
+        'par_p1': 36673,
+        'par_p10': 30,
+        'par_p2': -10515,
+        'par_p3': 88,
+        'par_p4': 7310,
+        'par_p5': -129,
+        'par_p6': 30,
+        'par_p7': 46,
+        'par_p8': -3177,
+        'par_p9': -2379,
+        'par_t1': 26041,
+        'par_t2': 26469,
+        'par_t3': 3,
+        'range_sw_err': 0,
+        'res_heat_range': 1,
+        'res_heat_val': 48,
+        't_fine': 136667
+    }
+    for k, v in data.items():
+        setattr(calibration, k, v)
+    return calibration

library/tests/test_compensation.py

@@ -0,0 +1,41 @@
+import bme680
+
+
+def test_calc_temperature(smbus, calibration):
+    """Validate temperature calculation against mock calibration data."""
+    sensor = bme680.BME680()
+    sensor.calibration_data = calibration
+    assert sensor._calc_temperature(501240) == 2669
+    assert sensor.calibration_data.t_fine == 136667
+
+
+def test_calc_pressure(smbus, calibration):
+    """Validate pressure calculation against mock calibration data."""
+    sensor = bme680.BME680()
+    sensor.calibration_data = calibration
+    sensor._calc_temperature(501240)
+    assert sensor._calc_pressure(353485) == 98712
+
+
+def test_calc_humidity(smbus, calibration):
+    """Validate humidity calculation against mock calibration data."""
+    sensor = bme680.BME680()
+    sensor.calibration_data = calibration
+    sensor._calc_temperature(501240)
+    assert sensor._calc_humidity(19019) == 42402
+
+
+def test_calc_gas_resistance(smbus, calibration):
+    """Validate gas calculation against mock calibration data."""
+    sensor = bme680.BME680()
+    sensor.calibration_data = calibration
+    assert int(sensor._calc_gas_resistance(0, 0)) == 12946860
+
+
+def test_temp_offset(smbus, calibration):
+    """Validate temperature calculation with offset against mock calibration data."""
+    sensor = bme680.BME680()
+    sensor.calibration_data = calibration
+    sensor.set_temp_offset(1.99)
+    assert sensor._calc_temperature(501240) == 2669 + 199
+    assert sensor.calibration_data.t_fine == 146830

library/tests/test_setup.py

@@ -1,57 +1,13 @@
-import sys
-import mock
 import pytest
 import bme680
 
 
-class MockSMBus:
-    """Mock a basic non-presence SMBus device to cause BME680 to fail.
-
-    Returns 0 in all cases, so that CHIP_ID will never match.
-
-    """
-
-    def __init__(self, bus):  # noqa D107
-        pass
-
-    def read_byte_data(self, addr, register):
-        """Return 0 for all read attempts."""
-        return 0
-
-
-class MockSMBusPresent:
-    """Mock enough of the BME680 for the library to initialise and test."""
-
-    def __init__(self, bus):
-        """Initialise with test data."""
-        self.regs = [0 for _ in range(256)]
-        self.regs[bme680.CHIP_ID_ADDR] = bme680.CHIP_ID
-
-    def read_byte_data(self, addr, register):
-        """Read a single byte from fake registers."""
-        return self.regs[register]
-
-    def write_byte_data(self, addr, register, value):
-        """Write a single byte to fake registers."""
-        self.regs[register] = value
-
-    def read_i2c_block_data(self, addr, register, length):
-        """Read up to length bytes from register."""
-        return self.regs[register:register + length]
-
-
-def test_setup_not_present():
+def test_setup_not_present(smbus_notpresent):
     """Mock the adbsence of a BME680 and test initialisation."""
-    sys.modules['smbus'] = mock.MagicMock()
-    sys.modules['smbus'].SMBus = MockSMBus
-
     with pytest.raises(RuntimeError):
         sensor = bme680.BME680()  # noqa F841
 
 
-def test_setup_mock_present():
+def test_setup_mock_present(smbus):
     """Mock the presence of a BME680 and test initialisation."""
-    sys.modules['smbus'] = mock.MagicMock()
-    sys.modules['smbus'].SMBus = MockSMBusPresent
-
     sensor = bme680.BME680()  # noqa F841