from leanbench.lint import lint
from leanbench.project import project


def found(code):
    return lint(project(code))


def test_clean_statement_has_no_findings():
    code = "theorem t (G : Type*) [Group G] (g : G) : g * 1 = g := by sorry"
    assert found(code) == []


def test_unused_binder():
    assert "unused_binder:k" in found("theorem t (n k : ℕ) : n = n := by rfl")


def test_carrier_type_is_not_flagged_as_unused():
    assert not any(f.startswith("unused") for f in found(
        "theorem t (G : Type*) [Group G] (g : G) : g = g := by rfl"))


def test_natural_subtraction_hazard():
    assert "nat_subtraction" in found("theorem t (a b : ℕ) : a - b + b = a := by sorry")
    assert "nat_subtraction" not in found("theorem t (a b : ℤ) : a - b + b = a := by ring")


def test_integer_division_hazard():
    assert "integer_division" in found("theorem t (a : ℕ) : a / 2 * 2 = a := by sorry")


def test_trivial_goal_and_degenerate():
    assert "trivial_goal" in found("theorem t (n : ℕ) : True := by trivial")
    assert "degenerate" in found("theorem t : 2 + 2 = 4 := by norm_num")