Nitpick test_source, implement test_context. (#70)

Implement test_context

Tests that have implemented:
* async wake interval
* default resampler index
* doppler factor
* speed of sound
* distance model

tests/test_context.py

@@ -1,6 +1,7 @@
 # Source pytest module
 # Copyright (C) 2020  Ngô Ngọc Đức Huy
 # Copyright (C) 2020  Nguyễn Gia Phong
+# Copyright (C) 2020  Ngô Xuân Minh
 #
 # This file is part of palace.
 #
@@ -19,7 +20,10 @@
 
 """This pytest module tries to test the correctness of the class Context."""
 
-from palace import current_context, Context, MessageHandler
+from palace import current_context, distance_models, Context, MessageHandler
+from pytest import raises
+
+from math import inf
 
 
 def test_with_context(device):
@@ -48,3 +52,45 @@ def test_message_handler(device):
     assert context.message_handler is message_handler_test
     with context:
         assert current_context().message_handler is context.message_handler
+
+
+def test_async_wake_interval(device):
+    """Test read-write property async_wake_interval."""
+    with Context(device) as context:
+        context.async_wake_interval = 42
+        assert context.async_wake_interval == 42
+
+
+def test_default_resampler_index(device):
+    """Test return values default_resampler_index."""
+    with Context(device) as context:
+        index = context.default_resampler_index
+        assert index >= 0
+        assert len(context.available_resamplers) > index
+
+
+def test_doppler_factor(device):
+    """Test write property doppler_factor."""
+    with Context(device) as context:
+        context.doppler_factor = 4/9
+        context.doppler_factor = 9/4
+        context.doppler_factor = 0
+        context.doppler_factor = inf
+        with raises(ValueError): context.doppler_factor = -1
+
+
+def test_speed_of_sound(device):
+    """Test write property speed_of_sound."""
+    with Context(device) as context:
+        context.speed_of_sound = 5/7
+        context.speed_of_sound = 7/5
+        with raises(ValueError): context.speed_of_sound = 0
+        context.speed_of_sound = inf
+        with raises(ValueError): context.speed_of_sound = -1
+
+
+def test_distance_model(device):
+    """Test preset values distance_model."""
+    with Context(device) as context:
+        for model in distance_models: context.distance_model = model
+        with raises(ValueError): context.distance_model = 'EYYYYLMAO'

tests/test_source.py

@@ -40,7 +40,7 @@ def test_group(context):
 
 
 def test_priority(context):
-    """Test read-write property group."""
+    """Test read-write property priority."""
     with Source(context) as source:
         assert source.priority == 0
         source.priority = 42