def floats(min_value=None, max_value=None):
    """Returns a strategy which generates floats. If min_value is not None,
    all values will be >= min_value. If max_value is not None, all values will
    be <= max_value.

    Where not explicitly ruled out by the bounds, all of infinity, -infinity
    and NaN are possible values generated by this strategy.
    """

    for e in (min_value, max_value):
        if e is not None and math.isnan(e):
            raise InvalidArgument('nan is not a valid end point')

    if min_value == float('-inf'):
        min_value = None
    if max_value == float('inf'):
        max_value = None

    from hypothesis.searchstrategy.numbers import WrapperFloatStrategy, \
        GaussianFloatStrategy, BoundedFloatStrategy, ExponentialFloatStrategy,\
        JustIntFloats, NastyFloats, FullRangeFloats, \
        FixedBoundedFloatStrategy, FloatsFromBase
    if min_value is None and max_value is None:
        return WrapperFloatStrategy(GaussianFloatStrategy()
                                    | BoundedFloatStrategy()
                                    | ExponentialFloatStrategy()
                                    | JustIntFloats() | NastyFloats()
                                    | FullRangeFloats())
    elif min_value is not None and max_value is not None:
        if max_value < min_value:
            raise InvalidArgument('Cannot have max_value=%r < min_value=%r' %
                                  (max_value, min_value))
        elif min_value == max_value:
            return just(min_value)
        elif math.isinf(max_value - min_value):
            assert min_value < 0 and max_value > 0
            return floats(min_value=0, max_value=max_value) | floats(
                min_value=min_value, max_value=0)
        return FixedBoundedFloatStrategy(min_value, max_value)
    elif min_value is not None:
        return FloatsFromBase(
            base=min_value,
            sign=1,
        ) | just(float('inf'))
    else:
        assert max_value is not None
        return FloatsFromBase(base=max_value, sign=-1) | just(float('-inf'))
Beispiel #2
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@fails
@given(floats(), settings=TRY_HARDER)
def test_can_find_floats_that_do_not_round_trip_through_reprs(x):
    assert float(repr(x)) == x


@given(floats(), floats(), randoms())
def test_floats_are_in_range(x, y, rand):
    assume(not (math.isnan(x) or math.isnan(y)))
    assume(not (math.isinf(x) or math.isinf(y)))
    x, y = sorted((x, y))
    assume(x < y)

    with Settings(max_examples=10):

        @given(floats(x, y), random=rand)
        def test_is_in_range(t):
            assert x <= t <= y

    try:
        test_is_in_range()
    except Unsatisfiable:
        assume(False)


@fails_with(AssertionError)
@given(NastyFloats())
def test_can_use_just_nasty(x):
    assert not math.isnan(x)
Beispiel #3
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def floats(min_value=None, max_value=None):
    """Returns a strategy which generates floats. If min_value is not None,
    all values will be >= min_value. If max_value is not None, all values will
    be <= max_value.

    Where not explicitly ruled out by the bounds, all of infinity, -infinity
    and NaN are possible values generated by this strategy.
    """

    for e in (min_value, max_value):
        if e is not None and math.isnan(e):
            raise InvalidArgument(u'nan is not a valid end point')
    if min_value is not None:
        min_value = float(min_value)
    if max_value is not None:
        max_value = float(max_value)
    if min_value == float(u'-inf'):
        min_value = None
    if max_value == float(u'inf'):
        max_value = None

    from hypothesis.searchstrategy.numbers import WrapperFloatStrategy, \
        GaussianFloatStrategy, BoundedFloatStrategy, ExponentialFloatStrategy,\
        JustIntFloats, NastyFloats, FullRangeFloats, \
        FixedBoundedFloatStrategy, FloatsFromBase
    if min_value is None and max_value is None:
        return WrapperFloatStrategy(
            GaussianFloatStrategy() |
            BoundedFloatStrategy() |
            ExponentialFloatStrategy() |
            JustIntFloats() |
            NastyFloats() |
            FullRangeFloats()
        )
    elif min_value is not None and max_value is not None:
        if max_value < min_value:
            raise InvalidArgument(
                u'Cannot have max_value=%r < min_value=%r' % (
                    max_value, min_value
                ))
        elif min_value == max_value:
            return just(min_value)
        elif math.isinf(max_value - min_value):
            assert min_value < 0 and max_value > 0
            return floats(min_value=0, max_value=max_value) | floats(
                min_value=min_value, max_value=0
            )
        elif count_between_floats(min_value, max_value) > 1000:
            critical_values = [
                min_value, max_value, min_value + (max_value - min_value) / 2]
            if min_value <= 0 <= max_value:
                if not is_negative(max_value):
                    critical_values.append(0.0)
                if is_negative(min_value):
                    critical_values.append(-0.0)
            return FixedBoundedFloatStrategy(
                lower_bound=min_value, upper_bound=max_value
            ) | sampled_from(critical_values)
        elif is_negative(max_value):
            assert is_negative(min_value)
            ub_int = float_to_int(max_value)
            lb_int = float_to_int(min_value)
            assert ub_int <= lb_int
            return integers(min_value=ub_int, max_value=lb_int).map(
                int_to_float
            )
        elif is_negative(min_value):
            return floats(min_value=min_value, max_value=-0.0) | floats(
                min_value=0, max_value=max_value
            )
        else:
            ub_int = float_to_int(max_value)
            lb_int = float_to_int(min_value)
            assert lb_int <= ub_int
            return integers(min_value=lb_int, max_value=ub_int).map(
                int_to_float
            )
    elif min_value is not None:
        critical_values = [min_value, float(u'inf')]
        if is_negative(min_value):
            critical_values.append(-0.0)
        if min_value <= 0:
            critical_values.append(0.0)
        return FloatsFromBase(
            base=min_value, sign=1,
        ) | sampled_from(critical_values)
    else:
        assert max_value is not None
        critical_values = [max_value, float(u'-inf')]
        if max_value >= 0:
            critical_values.append(-0.0)
            if not is_negative(max_value):
                critical_values.append(0.0)
        return FloatsFromBase(
            base=max_value, sign=-1
        ) | sampled_from(critical_values)
Beispiel #4
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@given(floats(), floats(), integers())
def test_floats_are_in_range(x, y, s):
    assume(not (math.isnan(x) or math.isnan(y)))
    assume(not (math.isinf(x) or math.isinf(y)))
    x, y = sorted((x, y))
    assume(x < y)

    @given(floats(x, y))
    @seed(s)
    @settings(max_examples=10)
    def test_is_in_range(t):
        assert x <= t <= y

    try:
        test_is_in_range()
    except Unsatisfiable:
        assume(False)


@fails_with(AssertionError)
@given(NastyFloats())
def test_can_use_just_nasty(x):
    assert not math.isnan(x)


@given(NastyFloats(allow_nan=False))
def test_nasty_filter_nan(x):
    assert not math.isnan(x)
Beispiel #5
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def floats(min_value=None,
           max_value=None,
           allow_nan=None,
           allow_infinity=None):
    """Returns a strategy which generates floats.

    - If min_value is not None, all values will be >= min_value.
    - If max_value is not None, all values will be <= max_value.
    - If min_value or max_value is not None, it is an error to enable
      allow_nan.
    - If both min_value and max_value are not None, it is an error to enable
      allow_infinity.

    Where not explicitly ruled out by the bounds, all of infinity, -infinity
    and NaN are possible values generated by this strategy.

    """

    if allow_nan is None:
        allow_nan = bool(min_value is None and max_value is None)
    elif allow_nan:
        if min_value is not None or max_value is not None:
            raise InvalidArgument(
                'Cannot have allow_nan=%r, with min_value or max_value' %
                (allow_nan))

    check_valid_bound(min_value, 'min_value')
    check_valid_bound(max_value, 'max_value')
    check_valid_interval(min_value, max_value, 'min_value', 'max_value')
    if min_value is not None:
        min_value = float(min_value)
    if max_value is not None:
        max_value = float(max_value)
    if min_value == float(u'-inf'):
        min_value = None
    if max_value == float(u'inf'):
        max_value = None

    if allow_infinity is None:
        allow_infinity = bool(min_value is None or max_value is None)
    elif allow_infinity:
        if min_value is not None and max_value is not None:
            raise InvalidArgument(
                'Cannot have allow_infinity=%r, with both min_value and '
                'max_value' % (allow_infinity))

    from hypothesis.searchstrategy.numbers import WrapperFloatStrategy, \
        GaussianFloatStrategy, BoundedFloatStrategy, ExponentialFloatStrategy,\
        JustIntFloats, NastyFloats, FullRangeFloats, \
        FixedBoundedFloatStrategy
    if min_value is None and max_value is None:
        return WrapperFloatStrategy(
            GaussianFloatStrategy() | BoundedFloatStrategy()
            | ExponentialFloatStrategy() | JustIntFloats()
            | NastyFloats(allow_nan, allow_infinity)
            | FullRangeFloats(allow_nan, allow_infinity))
    elif min_value is not None and max_value is not None:
        if min_value == max_value:
            return just(min_value)
        elif math.isinf(max_value - min_value):
            assert min_value < 0 and max_value > 0
            return floats(min_value=0, max_value=max_value) | floats(
                min_value=min_value, max_value=0)
        elif count_between_floats(min_value, max_value) > 1000:
            critical_values = [
                min_value, max_value, min_value + (max_value - min_value) / 2
            ]
            if min_value <= 0 <= max_value:
                if not is_negative(max_value):
                    critical_values.append(0.0)
                if is_negative(min_value):
                    critical_values.append(-0.0)
            return FixedBoundedFloatStrategy(
                lower_bound=min_value,
                upper_bound=max_value) | sampled_from(critical_values)
        elif is_negative(max_value):
            assert is_negative(min_value)
            ub_int = float_to_int(max_value)
            lb_int = float_to_int(min_value)
            assert ub_int <= lb_int
            return integers(min_value=ub_int,
                            max_value=lb_int).map(int_to_float)
        elif is_negative(min_value):
            return floats(min_value=min_value, max_value=-0.0) | floats(
                min_value=0, max_value=max_value)
        else:
            ub_int = float_to_int(max_value)
            lb_int = float_to_int(min_value)
            assert lb_int <= ub_int
            return integers(min_value=lb_int,
                            max_value=ub_int).map(int_to_float)
    elif min_value is not None:
        critical_values = [min_value]
        if allow_infinity:
            critical_values.append(float(u'inf'))
        if is_negative(min_value):
            critical_values.append(-0.0)
        if min_value <= 0:
            critical_values.append(0.0)
        return (floats(
            allow_infinity=allow_infinity,
            allow_nan=False).map(lambda x: assume(not math.isnan(
                x)) and min_value + abs(x))) | sampled_from(critical_values)
    else:
        assert max_value is not None
        critical_values = [max_value]
        if allow_infinity:
            critical_values.append(float(u'-inf'))
        if max_value >= 0:
            critical_values.append(-0.0)
            if not is_negative(max_value):
                critical_values.append(0.0)
        return (floats(
            allow_infinity=allow_infinity,
            allow_nan=False).map(lambda x: assume(not math.isnan(
                x)) and max_value - abs(x))) | sampled_from(critical_values)