From 6037e43f6c8acb0e52552d3fba20ff0ec2e3c981 Mon Sep 17 00:00:00 2001
From: Bas Schoenmaeckers <b.schoenmaeckers@zandersgroup.com>
Date: Tue, 30 Jun 2026 19:58:38 +0200
Subject: [PATCH 1/2] Add more abstract functions to c-api

---
 crates/capi/src/abstract_.rs | 59 +++++++++++++++++++++++++++++++++++-
 1 file changed, 58 insertions(+), 1 deletion(-)

diff --git a/crates/capi/src/abstract_.rs b/crates/capi/src/abstract_.rs
index cd390135be4..0867302406e 100644
--- a/crates/capi/src/abstract_.rs
+++ b/crates/capi/src/abstract_.rs
@@ -1,6 +1,6 @@
 use crate::{PyObject, pystate::with_vm};
 use alloc::slice;
-use core::ffi::c_int;
+use core::ffi::{CStr, c_char, c_int};
 pub use iter::*;
 pub use mapping::*;
 pub use number::*;
@@ -57,6 +57,21 @@ pub unsafe extern "C" fn PyObject_CallNoArgs(callable: *mut PyObject) -> *mut Py
     with_vm(|vm| unsafe { &*callable }.call((), vm))
 }
 
+#[unsafe(no_mangle)]
+pub unsafe extern "C" fn PyObject_CallObject(
+    callable: *mut PyObject,
+    args: *mut PyObject,
+) -> *mut PyObject {
+    with_vm(|vm| {
+        let callable = unsafe { &*callable };
+        if let Some(args) = unsafe { args.as_ref() } {
+            callable.call(tuple_to_args(args.try_downcast_ref::<PyTuple>(vm)?), vm)
+        } else {
+            callable.call((), vm)
+        }
+    })
+}
+
 #[unsafe(no_mangle)]
 pub unsafe extern "C" fn PyObject_Vectorcall(
     callable: *mut PyObject,
@@ -121,6 +136,15 @@ pub unsafe extern "C" fn PyObject_VectorcallMethod(
     })
 }
 
+#[unsafe(no_mangle)]
+pub unsafe extern "C" fn PyVectorcall_Call(
+    callable: *mut PyObject,
+    tuple: *mut PyObject,
+    kwargs: *mut PyObject,
+) -> *mut PyObject {
+    unsafe { PyObject_Call(callable, tuple, kwargs) }
+}
+
 #[unsafe(no_mangle)]
 pub unsafe extern "C" fn PyObject_GetItem(obj: *mut PyObject, key: *mut PyObject) -> *mut PyObject {
     with_vm(|vm| {
@@ -153,6 +177,29 @@ pub unsafe extern "C" fn PyObject_DelItem(obj: *mut PyObject, key: *mut PyObject
     })
 }
 
+#[unsafe(no_mangle)]
+pub unsafe extern "C" fn PyObject_DelItemString(obj: *mut PyObject, key: *const c_char) -> c_int {
+    with_vm(|vm| {
+        let obj = unsafe { &*obj };
+        let key = unsafe { CStr::from_ptr(key) }
+            .to_str()
+            .map_err(|_| vm.new_value_error("mapping key must be valid UTF-8"))?;
+        obj.del_item(key, vm)
+    })
+}
+
+#[unsafe(no_mangle)]
+pub unsafe extern "C" fn PyObject_Format(
+    obj: *mut PyObject,
+    format_spec: *mut PyObject,
+) -> *mut PyObject {
+    with_vm(|vm| {
+        let obj = unsafe { &*obj };
+        let format_spec = unsafe { &*format_spec }.try_downcast_ref::<PyStr>(vm)?;
+        vm.format(obj, format_spec.to_owned())
+    })
+}
+
 #[unsafe(no_mangle)]
 pub unsafe extern "C" fn PyObject_IsSubclass(derived: *mut PyObject, cls: *mut PyObject) -> c_int {
     with_vm(|vm| {
@@ -179,6 +226,16 @@ pub unsafe extern "C" fn PyObject_Size(obj: *mut PyObject) -> isize {
     })
 }
 
+#[unsafe(no_mangle)]
+pub unsafe extern "C" fn PyObject_Length(obj: *mut PyObject) -> isize {
+    unsafe { PyObject_Size(obj) }
+}
+
+#[unsafe(no_mangle)]
+pub unsafe extern "C" fn PyObject_Type(obj: *mut PyObject) -> *mut PyObject {
+    with_vm(|_vm| unsafe { &*obj }.obj_type())
+}
+
 #[cfg(test)]
 mod tests {
     use pyo3::prelude::*;

From 3301c679b3709d48cbf672af46412f9cb340a76c Mon Sep 17 00:00:00 2001
From: Bas Schoenmaeckers <b.schoenmaeckers@zandersgroup.com>
Date: Tue, 30 Jun 2026 20:27:13 +0200
Subject: [PATCH 2/2] Review

---
 crates/capi/src/abstract_.rs | 36 +++++++++++++++++++++++++++++++++---
 1 file changed, 33 insertions(+), 3 deletions(-)

diff --git a/crates/capi/src/abstract_.rs b/crates/capi/src/abstract_.rs
index 0867302406e..36d949a3022 100644
--- a/crates/capi/src/abstract_.rs
+++ b/crates/capi/src/abstract_.rs
@@ -142,7 +142,34 @@ pub unsafe extern "C" fn PyVectorcall_Call(
     tuple: *mut PyObject,
     kwargs: *mut PyObject,
 ) -> *mut PyObject {
-    unsafe { PyObject_Call(callable, tuple, kwargs) }
+    with_vm(|vm| {
+        let callable = unsafe { &*callable };
+        let tuple = unsafe { &*tuple }.try_downcast_ref::<PyTuple>(vm)?;
+
+        let mut args = tuple.iter().cloned().collect::<Vec<_>>();
+        let num_positional_args = args.len();
+
+        let mut kwnames = Vec::new();
+        if let Some(kwargs) = unsafe { kwargs.as_ref() } {
+            let kwargs = kwargs.try_downcast_ref::<PyDict>(vm)?;
+            for (key, value) in kwargs.items_vec() {
+                let key = key
+                    .downcast_ref::<PyStr>()
+                    .map(ToOwned::to_owned)
+                    .ok_or_else(|| vm.new_type_error("keywords must be strings"))?;
+                kwnames.push(key.into());
+                args.push(value);
+            }
+        }
+
+        let kwnames = if kwnames.is_empty() {
+            None
+        } else {
+            Some(kwnames.as_slice())
+        };
+
+        callable.vectorcall(args, num_positional_args, kwnames, vm)
+    })
 }
 
 #[unsafe(no_mangle)]
@@ -195,8 +222,11 @@ pub unsafe extern "C" fn PyObject_Format(
 ) -> *mut PyObject {
     with_vm(|vm| {
         let obj = unsafe { &*obj };
-        let format_spec = unsafe { &*format_spec }.try_downcast_ref::<PyStr>(vm)?;
-        vm.format(obj, format_spec.to_owned())
+        let spec = unsafe { format_spec.as_ref() }
+            .map(|spec| spec.try_downcast_ref::<PyStr>(vm))
+            .transpose()?
+            .unwrap_or_else(|| vm.ctx.empty_str);
+        vm.format(obj, spec.to_owned())
     })
 }