Issue #15402: Add a __sizeof__ method to struct.Struct.
Initial patch by Serhiy Storchaka.
diff --git a/Lib/test/test_struct.py b/Lib/test/test_struct.py
index 2ccaad2..bd89950 100644
--- a/Lib/test/test_struct.py
+++ b/Lib/test/test_struct.py
@@ -556,6 +556,16 @@
s = struct.Struct('i')
s.__init__('ii')
+ def test_sizeof(self):
+ self.assertGreater(sys.getsizeof(struct.Struct('BHILfdspP')),
+ sys.getsizeof(struct.Struct('B')))
+ self.assertGreaterEqual(sys.getsizeof(struct.Struct('123B')),
+ sys.getsizeof(struct.Struct('B')))
+ self.assertGreaterEqual(sys.getsizeof(struct.Struct('B' * 123)),
+ sys.getsizeof(struct.Struct('123B')))
+ self.assertGreaterEqual(sys.getsizeof(struct.Struct('123xB')),
+ sys.getsizeof(struct.Struct('B')))
+
def test_main():
run_unittest(StructTest)
diff --git a/Misc/NEWS b/Misc/NEWS
index ff7be30..539c905 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -98,6 +98,10 @@
Library
-------
+- Issue #15402: An issue in the struct module that caused sys.getsizeof to
+ return incorrect results for struct.Struct instances has been fixed.
+ Initial patch by Serhiy Storchaka.
+
- Issue #15232: when mangle_from is True, email.Generator now correctly mangles
lines that start with 'From' that occur in a MIME preamble or epilogue.
diff --git a/Modules/_struct.c b/Modules/_struct.c
index 1604b90..0a09fd8 100644
--- a/Modules/_struct.c
+++ b/Modules/_struct.c
@@ -1665,6 +1665,22 @@
return PyLong_FromSsize_t(self->s_size);
}
+PyDoc_STRVAR(s_sizeof__doc__,
+"S.__sizeof__() -> size of S in memory, in bytes");
+
+static PyObject *
+s_sizeof(PyStructObject *self)
+{
+ Py_ssize_t size;
+ formatcode *code;
+
+ size = sizeof(PyStructObject) + sizeof(formatcode);
+ for (code = self->s_codes; code->fmtdef != NULL; code++) {
+ size += sizeof(formatcode);
+ }
+ return PyLong_FromSsize_t(size);
+}
+
/* List of functions */
static struct PyMethodDef s_methods[] = {
@@ -1673,6 +1689,7 @@
{"unpack", s_unpack, METH_O, s_unpack__doc__},
{"unpack_from", (PyCFunction)s_unpack_from, METH_VARARGS|METH_KEYWORDS,
s_unpack_from__doc__},
+ {"__sizeof__", (PyCFunction)s_sizeof, METH_NOARGS, s_sizeof__doc__},
{NULL, NULL} /* sentinel */
};