view Modules/testcapi_long.h @ 87690:66c1c9f32567 default tip

Add use_weakref option to functools.lru_cache The use_weakref option makes lru_cache create weak references to the function arguments when creating the cache key, which prevents them from staying in the memory forever even after all other references to them are gone. This is a proof of concept for http://bugs.python.org/issue19859
author Radomir Dopieralski <devel@sheep.art.pl>
date Tue, 03 Dec 2013 16:02:48 +0100
parents 71100ef4f7a2
children
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/* Poor-man's template.  Macros used:
   TESTNAME     name of the test (like test_long_api_inner)
   TYPENAME     the signed type (like long)
   F_S_TO_PY    convert signed to pylong; TYPENAME -> PyObject*
   F_PY_TO_S    convert pylong to signed; PyObject* -> TYPENAME
   F_U_TO_PY    convert unsigned to pylong; unsigned TYPENAME -> PyObject*
   F_PY_TO_U    convert pylong to unsigned; PyObject* -> unsigned TYPENAME
*/

static PyObject *
TESTNAME(PyObject *error(const char*))
{
    const int NBITS = sizeof(TYPENAME) * 8;
    unsigned TYPENAME base;
    PyObject *pyresult;
    int i;

    /* Note:  This test lets PyObjects leak if an error is raised.  Since
       an error should never be raised, leaks are impossible <wink>. */

    /* Test native -> PyLong -> native roundtrip identity.
     * Generate all powers of 2, and test them and their negations,
     * plus the numbers +-1 off from them.
     */
    base = 1;
    for (i = 0;
         i < NBITS + 1;  /* on last, base overflows to 0 */
         ++i, base <<= 1)
    {
        int j;
        for (j = 0; j < 6; ++j) {
            TYPENAME in, out;
            unsigned TYPENAME uin, uout;

            /* For 0, 1, 2 use base; for 3, 4, 5 use -base */
            uin = j < 3 ? base : 0U - base;

            /* For 0 & 3, subtract 1.
             * For 1 & 4, leave alone.
             * For 2 & 5, add 1.
             */
            uin += (unsigned TYPENAME)(TYPENAME)(j % 3 - 1);

            pyresult = F_U_TO_PY(uin);
            if (pyresult == NULL)
                return error(
                 "unsigned unexpected null result");

            uout = F_PY_TO_U(pyresult);
            if (uout == (unsigned TYPENAME)-1 && PyErr_Occurred())
                return error(
                    "unsigned unexpected -1 result");
            if (uout != uin)
                return error(
                    "unsigned output != input");
            UNBIND(pyresult);

            in = (TYPENAME)uin;
            pyresult = F_S_TO_PY(in);
            if (pyresult == NULL)
                return error(
                    "signed unexpected null result");

            out = F_PY_TO_S(pyresult);
            if (out == (TYPENAME)-1 && PyErr_Occurred())
                return error(
                    "signed unexpected -1 result");
            if (out != in)
                return error(
                    "signed output != input");
            UNBIND(pyresult);
        }
    }

    /* Overflow tests.  The loop above ensured that all limit cases that
     * should not overflow don't overflow, so all we need to do here is
     * provoke one-over-the-limit cases (not exhaustive, but sharp).
     */
    {
        PyObject *one, *x, *y;
        TYPENAME out;
        unsigned TYPENAME uout;

        one = PyLong_FromLong(1);
        if (one == NULL)
            return error(
                "unexpected NULL from PyLong_FromLong");

        /* Unsigned complains about -1? */
        x = PyNumber_Negative(one);
        if (x == NULL)
            return error(
                "unexpected NULL from PyNumber_Negative");

        uout = F_PY_TO_U(x);
        if (uout != (unsigned TYPENAME)-1 || !PyErr_Occurred())
            return error(
                "PyLong_AsUnsignedXXX(-1) didn't complain");
        if (!PyErr_ExceptionMatches(PyExc_OverflowError))
            return error(
                "PyLong_AsUnsignedXXX(-1) raised "
                "something other than OverflowError");
        PyErr_Clear();
        UNBIND(x);

        /* Unsigned complains about 2**NBITS? */
        y = PyLong_FromLong((long)NBITS);
        if (y == NULL)
            return error(
                "unexpected NULL from PyLong_FromLong");

        x = PyNumber_Lshift(one, y); /* 1L << NBITS, == 2**NBITS */
        UNBIND(y);
        if (x == NULL)
            return error(
                "unexpected NULL from PyNumber_Lshift");

        uout = F_PY_TO_U(x);
        if (uout != (unsigned TYPENAME)-1 || !PyErr_Occurred())
            return error(
                "PyLong_AsUnsignedXXX(2**NBITS) didn't "
                "complain");
        if (!PyErr_ExceptionMatches(PyExc_OverflowError))
            return error(
                "PyLong_AsUnsignedXXX(2**NBITS) raised "
                "something other than OverflowError");
        PyErr_Clear();

        /* Signed complains about 2**(NBITS-1)?
           x still has 2**NBITS. */
        y = PyNumber_Rshift(x, one); /* 2**(NBITS-1) */
        UNBIND(x);
        if (y == NULL)
            return error(
                "unexpected NULL from PyNumber_Rshift");

        out = F_PY_TO_S(y);
        if (out != (TYPENAME)-1 || !PyErr_Occurred())
            return error(
                "PyLong_AsXXX(2**(NBITS-1)) didn't "
                "complain");
        if (!PyErr_ExceptionMatches(PyExc_OverflowError))
            return error(
                "PyLong_AsXXX(2**(NBITS-1)) raised "
                "something other than OverflowError");
        PyErr_Clear();

        /* Signed complains about -2**(NBITS-1)-1?;
           y still has 2**(NBITS-1). */
        x = PyNumber_Negative(y);  /* -(2**(NBITS-1)) */
        UNBIND(y);
        if (x == NULL)
            return error(
                "unexpected NULL from PyNumber_Negative");

        y = PyNumber_Subtract(x, one); /* -(2**(NBITS-1))-1 */
        UNBIND(x);
        if (y == NULL)
            return error(
                "unexpected NULL from PyNumber_Subtract");

        out = F_PY_TO_S(y);
        if (out != (TYPENAME)-1 || !PyErr_Occurred())
            return error(
                "PyLong_AsXXX(-2**(NBITS-1)-1) didn't "
                "complain");
        if (!PyErr_ExceptionMatches(PyExc_OverflowError))
            return error(
                "PyLong_AsXXX(-2**(NBITS-1)-1) raised "
                "something other than OverflowError");
        PyErr_Clear();
        UNBIND(y);

        Py_XDECREF(x);
        Py_XDECREF(y);
        Py_DECREF(one);
    }

    /* Test F_PY_TO_{S,U} on non-pylong input. This should raise a TypeError. */
    {
        TYPENAME out;
        unsigned TYPENAME uout;

        Py_INCREF(Py_None);

        out = F_PY_TO_S(Py_None);
        if (out != (TYPENAME)-1 || !PyErr_Occurred())
            return error("PyLong_AsXXX(None) didn't complain");
        if (!PyErr_ExceptionMatches(PyExc_TypeError))
            return error("PyLong_AsXXX(None) raised "
                         "something other than TypeError");
        PyErr_Clear();

        uout = F_PY_TO_U(Py_None);
        if (uout != (unsigned TYPENAME)-1 || !PyErr_Occurred())
            return error("PyLong_AsXXX(None) didn't complain");
        if (!PyErr_ExceptionMatches(PyExc_TypeError))
            return error("PyLong_AsXXX(None) raised "
                         "something other than TypeError");
        PyErr_Clear();

        Py_DECREF(Py_None);
    }

    Py_INCREF(Py_None);
    return Py_None;
}