Math tests - issue #2785

tests/unit/test_math.py

@@ -1,89 +1,149 @@
-"""
-Unit tests for utils.py
-
-Can run these tests individually with:
-python -m pytest tests/unit/test_utils.py
-"""
-
-import arcade
-from pytest import approx
-from arcade.math import *
-from arcade.types import LBWH
-
-
-def test_lerp():
-    assert lerp(2.0, 4.0, 0.75) == approx(3.5)
-
-
-def test_lerp_2d():
-    vec = lerp_2d((0.0, 2.0), (8.0, 4.0), 0.25)
-    assert vec[0] == approx(2.0)
-    assert vec[1] == approx(2.5)
-    vec = lerp_2d((0.0, 2.0), (8.0, 4.0), -0.25)
-    assert vec[0] == approx(-2.0)
-    assert vec[1] == approx(1.5)
-
-
-def test_lerp_angle_normal():
-    assert lerp_angle(0, 90, 0.5) == 45
-
-
-def test_lerp_angle_backwards():
-    assert lerp_angle(90, 0, 0.5) == 45
-
-
-def test_lerp_angle_loop_around():
-    assert lerp_angle(355, 15, 0.5) == 5
-
-
-def test_lerp_angle_loop_around_backwards():
-    assert lerp_angle(10, 350, 0.5) == 0
-
-
-def test_lerp_angle_equal():
-    assert lerp_angle(50, 50, 0.5) == 50
-
-
-def test_lerp_angle_effectively_equal():
-    assert lerp_angle(50, 50 + 360, 0.5) == 50
-    assert lerp_angle(50 - 360, 50, 0.5) == 50
-
-
-def test_rand_in_rect():
-    """Smoke test"""
-    rand_in_rect(LBWH(10.0, 20.0, 30.5, 5.1))
-
-
-def test_rand_in_circle():
-    """Smoke test"""
-    rand_in_circle((0, 0), 10.0)
-
-
-def test_rand_on_circle():
-    """Smoke test"""
-    rand_on_circle((10.0, 20.0), 15.5)
-
-
-def test_rand_on_line():
-    """Smoke test"""
-    rand_on_line((-5.5, -2.2), (5.2, 14.7))
-
-
-def test_rand_angle_360_deg():
-    """Smoke test"""
-    rand_angle_360_deg()
-
-
-def test_rand_angle_spread_deg():
-    """Smoke test"""
-    rand_angle_spread_deg(45.0, 5.0)
-
-
-def test_rand_vec_spread_deg():
-    """Smoke test"""
-    rand_vec_spread_deg(-45.0, 5.0, 3.3)
-
-
-def test_rand_vec_magnitude():
-    """Smoke test"""
-    rand_vec_magnitude(30.5, 3.3, 4.4)
+"""
+Unit tests for utils.py
+
+Can run these tests individually with:
+python -m pytest tests/unit/test_utils.py
+"""
+
+import arcade
+from pytest import approx
+from arcade.math import *
+from arcade.types import LBWH
+import random
+import math
+import pytest
+
+
+@pytest.fixture(autouse=True)
+def set_random_seed():
+    random.seed(42) 
+    yield
+
+def test_lerp():
+    assert lerp(2.0, 4.0, 0.75) == approx(3.5)
+
+
+def test_lerp_2d():
+    vec = lerp_2d((0.0, 2.0), (8.0, 4.0), 0.25)
+    assert vec[0] == approx(2.0)
+    assert vec[1] == approx(2.5)
+    vec = lerp_2d((0.0, 2.0), (8.0, 4.0), -0.25)
+    assert vec[0] == approx(-2.0)
+    assert vec[1] == approx(1.5)
+
+
+def test_lerp_angle_normal():
+    assert lerp_angle(0, 90, 0.5) == 45
+
+
+def test_lerp_angle_backwards():
+    assert lerp_angle(90, 0, 0.5) == 45
+
+
+def test_lerp_angle_loop_around():
+    assert lerp_angle(355, 15, 0.5) == 5
+
+
+def test_lerp_angle_loop_around_backwards():
+    assert lerp_angle(10, 350, 0.5) == 0
+
+
+def test_lerp_angle_equal():
+    assert lerp_angle(50, 50, 0.5) == 50
+
+
+def test_lerp_angle_effectively_equal():
+    assert lerp_angle(50, 50 + 360, 0.5) == 50
+    assert lerp_angle(50 - 360, 50, 0.5) == 50
+
+
+def test_rand_in_rect():
+    rect = LBWH(10.0, 20.0, 30.5, 5.1)
+    for _ in range(10):
+        x, y = rand_in_rect(rect)
+        assert rect.left <= x <= rect.right
+        assert rect.bottom <= y <= rect.top
+    rect = LBWH(-10.0, -20.0, 30.5, 5.1)
+    for _ in range(10):
+        x, y = rand_in_rect(rect)
+        assert rect.left <= x <= rect.right
+        assert rect.bottom <= y <= rect.top
+
+
+def test_rand_in_rect_zero_size():
+    rect = LBWH(0.0, 0.0, 0.0, 0.0)
+    x, y = rand_in_rect(rect)
+    assert x == 0.0
+    assert y == 0.0
+
+
+
+
+def test_rand_in_circle():
+    center=(0, 0)
+    r=10.0
+    for _ in range(10):
+        x, y = rand_in_circle(center,r)
+        distance= math.sqrt((x-center[0])**2+(y-center[1])**2)
+        assert distance<=r
+
+
+def test_rand_on_circle():
+    center=(10.0, 20.0)
+    r=15.5
+    for _ in range(10):
+        x, y = rand_on_circle(center,r)
+        distance= math.sqrt((x-center[0])**2+(y-center[1])**2)
+        assert distance==approx(r)
+
+
+def test_rand_on_line():
+
+    point1=(-5.5, -2.2)
+    point2=(5.2, 14.7)
+    m=(point2[1]-point1[1])/(point2[0]-point1[0])
+    b=point1[1]-m*point1[0]
+    for _ in range(10):
+        random_point = rand_on_line((-5.5, -2.2),(5.2, 14.7))
+        assert random_point[1] == approx(m*random_point[0]+b)
+
+def test_rand_angle_360_deg():
+    for _ in range(5):
+       angle = rand_angle_360_deg()
+       assert 0.0 <= angle <= 360.0
+
+
+
+def test_rand_angle_spread_deg():
+    rand_angle_spread_deg(45.0, 5.0)
+    angle = 45.0
+    spread = 5.0
+    for _ in range(5):
+       new_angle = rand_angle_spread_deg(angle,spread)
+       assert angle - spread <= new_angle <= angle + spread
+
+
+
+def test_rand_vec_spread_deg():
+    rand_vec_spread_deg(-45.0, 5.0, 3.3)
+    angle = -45.0
+    half = 5.0
+    length = 3.3
+    for _ in range(200):
+        x, y = rand_vec_spread_deg(angle, half, length)  
+        mag = math.hypot(x, y)
+        assert mag == approx(length, rel=1e-7, abs=1e-7)
+
+
+
+def test_rand_vec_magnitude():
+    rand_vec_magnitude(30.5, 3.3, 4.4)
+    angle = 30.5
+    lo = 3.3
+    hi = 4.4
+    for _ in range(5):
+        x,y = rand_vec_magnitude(angle,lo,hi)
+        mag = math.hypot(x,y)
+        assert lo<= mag <=hi
+
+