From 45de5b2f81d6ef5ba0a45c0792403c230653ff1b Mon Sep 17 00:00:00 2001
From: Cloud User <presler.omer@gmail.com>
Date: Sat, 19 Jul 2025 07:53:07 -0400
Subject: [PATCH] Adding deepget method to dictionary

---
 Include/dictobject.h          |  1 -
 Objects/clinic/dictobject.c.h | 40 +++++++++++++++++++++++++++++++++++
 Objects/dictobject.c          | 35 ++++++++++++++++++++++++++++++
 3 files changed, 75 insertions(+), 1 deletion(-)

diff --git a/Include/dictobject.h b/Include/dictobject.h
index 1bbeec1ab699e7..cfd286f9ce941c 100644
--- a/Include/dictobject.h
+++ b/Include/dictobject.h
@@ -17,7 +17,6 @@ PyAPI_DATA(PyTypeObject) PyDict_Type;
 #define PyDict_Check(op) \
                  PyType_FastSubclass(Py_TYPE(op), Py_TPFLAGS_DICT_SUBCLASS)
 #define PyDict_CheckExact(op) Py_IS_TYPE((op), &PyDict_Type)
-
 PyAPI_FUNC(PyObject *) PyDict_New(void);
 PyAPI_FUNC(PyObject *) PyDict_GetItem(PyObject *mp, PyObject *key);
 PyAPI_FUNC(PyObject *) PyDict_GetItemWithError(PyObject *mp, PyObject *key);
diff --git a/Objects/clinic/dictobject.c.h b/Objects/clinic/dictobject.c.h
index abf6b38449fcb0..0cf5d44d9a0fd0 100644
--- a/Objects/clinic/dictobject.c.h
+++ b/Objects/clinic/dictobject.c.h
@@ -113,6 +113,46 @@ dict_get(PyObject *self, PyObject *const *args, Py_ssize_t nargs)
     return return_value;
 }
 
+PyDoc_STRVAR(dict_deepget__doc__,
+"deepget($self, keys, default=None, /)\n"
+"--\n"
+"\n"
+"Return the value for the nested keys if the full path exists in the dictionary, else return default.");
+
+#define DICT_DEEPGET_METHODDEF    \
+    {"deepget", _PyCFunction_CAST(dict_deepget), METH_FASTCALL, dict_deepget__doc__},
+
+static PyObject *
+dict_deepget_impl(PyDictObject *self, PyObject * const *keylist, PyObject *default_value);
+
+static PyObject *
+dict_deepget(PyObject *self, PyObject *const *args, Py_ssize_t nargs)
+{
+    PyObject *return_value = NULL;
+    PyObject *keylist;
+    PyObject *default_value = Py_None;
+
+    if (!_PyArg_CheckPositional("deepget", nargs, 1, 2)) {
+        goto exit;
+    }
+
+    keylist = args[0];
+    if (!PyList_Check(keylist)) {
+        PyErr_SetString(PyExc_TypeError, "keys must be provided as a list");
+        return NULL;
+    }
+
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    default_value = args[1];
+skip_optional:
+    return_value = dict_deepget_impl((PyDictObject *)self, keylist, default_value);
+
+exit:
+    return return_value;
+}
+
 PyDoc_STRVAR(dict_setdefault__doc__,
 "setdefault($self, key, default=None, /)\n"
 "--\n"
diff --git a/Objects/dictobject.c b/Objects/dictobject.c
index 0ed52ac5e87b6e..57acfda7e6cd3f 100644
--- a/Objects/dictobject.c
+++ b/Objects/dictobject.c
@@ -4312,6 +4312,40 @@ dict_get_impl(PyDictObject *self, PyObject *key, PyObject *default_value)
     return val;
 }
 
+static PyObject *
+dict_deepget_impl(PyDictObject *self, PyObject * const *keylist, PyObject *default_value)
+{
+    Py_ssize_t n = PyList_GET_SIZE(keylist);
+    if (n == 0) {
+        return default_value;
+    }
+
+    PyObject *val = (PyObject *)self;  // Start with top-level dict
+    for (Py_ssize_t i = 0; i < n; i++) {
+        PyObject *key = PyList_GET_ITEM(keylist, i);
+
+        if (!PyDict_Check(val)) {
+            return default_value;
+        }
+
+        Py_hash_t hash = _PyObject_HashFast(key);
+        if (hash == -1) {
+            dict_unhashable_type(key);
+            return default_value;
+        }
+
+        PyObject *next = NULL;
+        Py_ssize_t ix = _Py_dict_lookup_threadsafe((PyDictObject *)val, key, hash, &next);
+        if (ix == DKIX_ERROR || ix == DKIX_EMPTY || next == NULL) {
+            return Py_NewRef(default_value);
+        }
+
+        val = next;
+    }
+
+    return Py_NewRef(val);
+}
+
 static int
 dict_setdefault_ref_lock_held(PyObject *d, PyObject *key, PyObject *default_value,
                     PyObject **result, int incref_result)
@@ -4741,6 +4775,7 @@ static PyMethodDef mapp_methods[] = {
      getitem__doc__},
     DICT___SIZEOF___METHODDEF
     DICT_GET_METHODDEF
+    DICT_DEEPGET_METHODDEF
     DICT_SETDEFAULT_METHODDEF
     DICT_POP_METHODDEF
     DICT_POPITEM_METHODDEF