1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144

// Copyright (c) 2017-present PyO3 Project and Contributors
//
// based on Daniel Grunwald's https://github.com/dgrunwald/rust-cpython
#[cfg(feature = "experimental-inspect")]
use crate::inspect::types::TypeInfo;
use crate::{
    ffi, AsPyPointer, FromPyObject, IntoPy, PyAny, PyErr, PyObject, PyResult, Python, ToPyObject,
};
use std::os::raw::c_double;

/// Represents a Python `float` object.
///
/// You can usually avoid directly working with this type
/// by using [`ToPyObject`](crate::conversion::ToPyObject)
/// and [`extract`](PyAny::extract)
/// with `f32`/`f64`.
#[repr(transparent)]
pub struct PyFloat(PyAny);

pyobject_native_type!(
    PyFloat,
    ffi::PyFloatObject,
    ffi::PyFloat_Type,
    #checkfunction=ffi::PyFloat_Check
);

impl PyFloat {
    /// Creates a new Python `float` object.
    pub fn new(py: Python<'_>, val: c_double) -> &PyFloat {
        unsafe { py.from_owned_ptr(ffi::PyFloat_FromDouble(val)) }
    }

    /// Gets the value of this float.
    pub fn value(&self) -> c_double {
        unsafe { ffi::PyFloat_AsDouble(self.as_ptr()) }
    }
}

impl ToPyObject for f64 {
    fn to_object(&self, py: Python<'_>) -> PyObject {
        PyFloat::new(py, *self).into()
    }
}

impl IntoPy<PyObject> for f64 {
    fn into_py(self, py: Python<'_>) -> PyObject {
        PyFloat::new(py, self).into()
    }

    #[cfg(feature = "experimental-inspect")]
    fn type_output() -> TypeInfo {
        TypeInfo::builtin("float")
    }
}

impl<'source> FromPyObject<'source> for f64 {
    // PyFloat_AsDouble returns -1.0 upon failure
    #![allow(clippy::float_cmp)]
    fn extract(obj: &'source PyAny) -> PyResult<Self> {
        let v = unsafe { ffi::PyFloat_AsDouble(obj.as_ptr()) };

        if v == -1.0 {
            if let Some(err) = PyErr::take(obj.py()) {
                return Err(err);
            }
        }

        Ok(v)
    }

    #[cfg(feature = "experimental-inspect")]
    fn type_input() -> TypeInfo {
        Self::type_output()
    }
}

impl ToPyObject for f32 {
    fn to_object(&self, py: Python<'_>) -> PyObject {
        PyFloat::new(py, f64::from(*self)).into()
    }
}

impl IntoPy<PyObject> for f32 {
    fn into_py(self, py: Python<'_>) -> PyObject {
        PyFloat::new(py, f64::from(self)).into()
    }

    #[cfg(feature = "experimental-inspect")]
    fn type_output() -> TypeInfo {
        TypeInfo::builtin("float")
    }
}

impl<'source> FromPyObject<'source> for f32 {
    fn extract(obj: &'source PyAny) -> PyResult<Self> {
        Ok(obj.extract::<f64>()? as f32)
    }

    #[cfg(feature = "experimental-inspect")]
    fn type_input() -> TypeInfo {
        Self::type_output()
    }
}

#[cfg(test)]
mod tests {
    #[cfg(not(Py_LIMITED_API))]
    use crate::ffi::PyFloat_AS_DOUBLE;
    #[cfg(not(Py_LIMITED_API))]
    use crate::AsPyPointer;
    use crate::{Python, ToPyObject};

    macro_rules! num_to_py_object_and_back (
        ($func_name:ident, $t1:ty, $t2:ty) => (
            #[test]
            fn $func_name() {
                use assert_approx_eq::assert_approx_eq;

                Python::with_gil(|py| {

                let val = 123 as $t1;
                let obj = val.to_object(py);
                assert_approx_eq!(obj.extract::<$t2>(py).unwrap(), val as $t2);
                });
            }
        )
    );

    num_to_py_object_and_back!(to_from_f64, f64, f64);
    num_to_py_object_and_back!(to_from_f32, f32, f32);
    num_to_py_object_and_back!(int_to_float, i32, f64);

    #[cfg(not(Py_LIMITED_API))]
    #[test]
    fn test_as_double_macro() {
        use assert_approx_eq::assert_approx_eq;

        Python::with_gil(|py| {
            let v = 1.23f64;
            let obj = v.to_object(py);
            assert_approx_eq!(v, unsafe { PyFloat_AS_DOUBLE(obj.as_ptr()) });
        });
    }
}