import py

from rpython.rtyper.lltypesystem import lltype
from rpython.translator.translator import TranslationContext
from rpython.translator.c.test.test_genc import compile


class TestRefcount(object):
    def compile_func(self, func, args):
        return compile(func, args, gcpolicy='ref')

    def test_something(self):
        def f():
            return 1
        fn = self.compile_func(f, [])
        assert fn() == 1

    def test_something_more(self):
        S = lltype.GcStruct("S", ('x', lltype.Signed))
        def f(x):
            s = lltype.malloc(S)
            s.x = x
            return s.x
        fn = self.compile_func(f, [int])
        assert fn(1) == 1

    def test_call_function(self):
        class C:
            pass
        def f():
            c = C()
            c.x = 1
            return c
        def g():
            return f().x
        fn = self.compile_func(g, [])
        assert fn() == 1

    def test_multiple_exits(self):
        S = lltype.GcStruct("S", ('x', lltype.Signed))
        T = lltype.GcStruct("T", ('y', lltype.Signed))
        def f(n):
            c = lltype.malloc(S)
            d = lltype.malloc(T)
            d.y = 1
            e = lltype.malloc(T)
            e.y = 2
            if n:
                x = d
            else:
                x = e
            return x.y
        fn = self.compile_func(f, [int])
        assert fn(1) == 1
        assert fn(0) == 2


    def test_cleanup_vars_on_call(self):
        S = lltype.GcStruct("S", ('x', lltype.Signed))
        def f():
            return lltype.malloc(S)
        def g():
            s1 = f()
            s1.x = 42
            s2 = f()
            s3 = f()
            return s1.x
        fn = self.compile_func(g, [])
        assert fn() == 42

    def test_multiply_passed_var(self):
        S = lltype.GcStruct("S", ('x', lltype.Signed))
        def f(x):
            if x:
                a = lltype.malloc(S)
                a.x = 1
                b = a
            else:
                a = lltype.malloc(S)
                a.x = 1
                b = lltype.malloc(S)
                b.x = 2
            return a.x + b.x
        fn = self.compile_func(f, [int])
        fn(1) == 2
        fn(0) == 3

    def test_write_barrier(self):
        S = lltype.GcStruct("S", ('x', lltype.Signed))
        T = lltype.GcStruct("T", ('s', lltype.Ptr(S)))
        def f(x):
            s = lltype.malloc(S)
            s.x = 0
            s1 = lltype.malloc(S)
            s1.x = 1
            s2 = lltype.malloc(S)
            s2.x = 2
            t = lltype.malloc(T)
            t.s = s
            if x:
                t.s = s1
            else:
                t.s = s2
            return t.s.x + s.x + s1.x + s2.x
        fn = self.compile_func(f, [int])
        assert fn(1) == 4
        assert fn(0) == 5

    def test_del_catches(self):
        import os
        def g():
            pass
        class A(object):
            def __del__(self):
                try:
                    g()
                except:
                    pass  #os.write(1, "hallo")
        def f1(i):
            if i:
                raise TypeError
        def f(i):
            a = A()
            f1(i)
            a.b = 1
            return a.b
        fn = self.compile_func(f, [int])
        assert fn(0) == 1
        fn(1, expected_exception_name="TypeError")

    def test_del_raises(self):
        class B(object):
            def __del__(self):
                raise TypeError
        def func():
            b = B()
        fn = self.compile_func(func, [])
        # does not crash
        fn()

    def test_wrong_order_setitem(self):
        class A(object):
            pass
        a = A()
        a.b = None
        class B(object):
            def __del__(self):
                a.freed += 1
                a.b = None
        def f(n):
            a.freed = 0
            a.b = B()
            if n:
                a.b = None
            return a.freed
        fn = self.compile_func(f, [int])
        res = fn(1)
        assert res == 1