add tests for njint_brentq

solidago/tests/test_solvers.py

@@ -1,7 +1,35 @@
 import pytest
+from numba import njit
+
+from solidago.solvers.dichotomy import solve as dichotomy_solve
+from solidago.solvers.optimize import njit_brentq as brentq
 
-from solidago.solvers.dichotomy import solve
 
 def test_dichotomy():
-    assert solve(lambda t: t, 1, 0, 3) == pytest.approx(1, abs=1e-4)
-    assert solve(lambda t: 2 - t**2, 1, 0, 3) == pytest.approx(1, abs=1e-4)
+    assert dichotomy_solve(lambda t: t, 1, 0, 3) == pytest.approx(1, abs=1e-4)
+    assert dichotomy_solve(lambda t: 2 - t**2, 1, 0, 3) == pytest.approx(1, abs=1e-4)
+
+
+def test_brentq_fails_to_converge_for_non_zero_method():
+    @njit
+    def one_plus_x_square(x):
+        return 1 + x * x
+
+    with pytest.raises(ValueError):
+        brentq(one_plus_x_square, extend_bounds="no")
+
+
+def test_brentq_finds_zeros_of_simple_increasing_linear():
+    @njit
+    def x_plus_five(x):
+        return x + 5
+
+    assert brentq(x_plus_five, extend_bounds="ascending") == -5.0
+
+
+def test_brentq_finds_zeros_of_simple_decreasing_linear():
+    @njit
+    def minus_x_plus_twelve(x):
+        return -x + 12
+
+    assert brentq(minus_x_plus_twelve, extend_bounds="descending") == 12.0