gh-111495: Add tests for PyComplex C API (GH-111591)

Modules/_testcapi/complex.c

@@ -1,7 +1,99 @@
 #include "parts.h"
 #include "util.h"
 
+
+static PyObject *
+complex_check(PyObject *Py_UNUSED(module), PyObject *obj)
+{
+    NULLABLE(obj);
+    return PyLong_FromLong(PyComplex_Check(obj));
+}
+
+static PyObject *
+complex_checkexact(PyObject *Py_UNUSED(module), PyObject *obj)
+{
+    NULLABLE(obj);
+    return PyLong_FromLong(PyComplex_CheckExact(obj));
+}
+
+static PyObject *
+complex_fromccomplex(PyObject *Py_UNUSED(module), PyObject *obj)
+{
+    Py_complex complex;
+
+    if (!PyArg_Parse(obj, "D", &complex)) {
+        return NULL;
+    }
+
+    return PyComplex_FromCComplex(complex);
+}
+
+static PyObject *
+complex_fromdoubles(PyObject *Py_UNUSED(module), PyObject *args)
+{
+    double real, imag;
+
+    if (!PyArg_ParseTuple(args, "dd", &real, &imag)) {
+        return NULL;
+    }
+
+    return PyComplex_FromDoubles(real, imag);
+}
+
+static PyObject *
+complex_realasdouble(PyObject *Py_UNUSED(module), PyObject *obj)
+{
+    double real;
+
+    NULLABLE(obj);
+    real = PyComplex_RealAsDouble(obj);
+
+    if (real == -1. && PyErr_Occurred()) {
+        return NULL;
+    }
+
+    return PyFloat_FromDouble(real);
+}
+
+static PyObject *
+complex_imagasdouble(PyObject *Py_UNUSED(module), PyObject *obj)
+{
+    double imag;
+
+    NULLABLE(obj);
+    imag = PyComplex_ImagAsDouble(obj);
+
+    if (imag == -1. && PyErr_Occurred()) {
+        return NULL;
+    }
+
+    return PyFloat_FromDouble(imag);
+}
+
+static PyObject *
+complex_asccomplex(PyObject *Py_UNUSED(module), PyObject *obj)
+{
+    Py_complex complex;
+
+    NULLABLE(obj);
+    complex = PyComplex_AsCComplex(obj);
+
+    if (complex.real == -1. && PyErr_Occurred()) {
+        return NULL;
+    }
+
+    return PyComplex_FromCComplex(complex);
+}
+
+
 static PyMethodDef test_methods[] = {
+    {"complex_check", complex_check, METH_O},
+    {"complex_checkexact", complex_checkexact, METH_O},
+    {"complex_fromccomplex", complex_fromccomplex, METH_O},
+    {"complex_fromdoubles", complex_fromdoubles, METH_VARARGS},
+    {"complex_realasdouble", complex_realasdouble, METH_O},
+    {"complex_imagasdouble", complex_imagasdouble, METH_O},
+    {"complex_asccomplex", complex_asccomplex, METH_O},
     {NULL},
 };