import math
import sys, os
sys.path.insert(0, os.path.dirname(__file__))
from expr_eval import evaluate, EvalError

def test_basic():
    assert evaluate("2 + 3 * 4") == 14
    assert evaluate("(2+3)*4") == 20
    assert evaluate("10 / 3") == 10/3
    assert evaluate("10 // 3") == 3
    assert evaluate("10 % 3") == 1

def test_power_precedence():
    # unary binds looser than ** (matches Python)
    assert evaluate("-2**2") == -4
    assert evaluate("(-2)**2") == 4
    assert evaluate("2**-2") == 0.25
    assert evaluate("2**3**2") == 512

def test_unary():
    assert evaluate("--5") == 5
    assert evaluate("-(-3)") == 3

def test_funcs():
    assert evaluate("sqrt(16)") == 4
    assert abs(evaluate("sin(0)")) < 1e-12
    assert evaluate("max(1,2,3)") == 3
    assert evaluate("min(1,2,3)") == 1
    assert evaluate("abs(-7)") == 7

def test_vars():
    assert evaluate("x + pi", {"x": 3, "pi": math.pi}) == 3 + math.pi

def test_errors():
    for e in ["2 +", "1/0", "foo", "2 @ 3", "sqrt(-1)"]:
        try:
            evaluate(e)
            raise AssertionError(f"no error for {e!r}")
        except EvalError:
            pass

if __name__ == "__main__":
    # run all test_ functions
    import traceback
    g = globals()
    failed = 0
    for name in sorted(n for n in g if n.startswith("test_")):
        try:
            g[name]()
            print("PASS", name)
        except Exception:
            failed += 1
            print("FAIL", name)
            traceback.print_exc()
    print("FAILED:", failed)
    sys.exit(1 if failed else 0)