Add with_vm helper

RustPython · bschoenmaeckers · Apr 4, 2026 · Apr 5, 2026 · Apr 5, 2026 · Apr 5, 2026
commit d5e66d0d833f1df93da770c1d83e9f3d82ea3209
diff --git a/crates/capi/src/longobject.rs b/crates/capi/src/longobject.rs
@@ -2,22 +2,15 @@ use core::ffi::{c_long, c_longlong, c_ulong, c_ulonglong};
 use core::ptr;
 
 use crate::PyObject;
-use crate::pylifecycle::INTERP;
+use crate::pylifecycle::with_vm;
 use rustpython_vm::PyObjectRef;
 use rustpython_vm::builtins::PyInt;
 
 #[unsafe(no_mangle)]
 pub extern "C" fn PyLong_FromLong(value: c_long) -> *mut PyObject {
-    INTERP.with(|interp_ref| {
-        let interp = interp_ref.borrow();
-        let interp = interp
-            .as_ref()
-            .expect("PyLong_FromLong called before Py_InitializeEx");
-
-        interp.enter(|vm| {
-            let obj: PyObjectRef = vm.ctx.new_int(value).into();
-            obj.into_raw().as_ptr()
-        })
+    with_vm(|vm| {
+        let obj: PyObjectRef = vm.ctx.new_int(value).into();
+        obj.into_raw().as_ptr()
     })
 }
 
@@ -57,23 +50,16 @@ pub extern "C" fn PyLong_AsLong(obj: *mut PyObject) -> c_long {
         panic!("PyLong_AsLong called with null object");
     }
 
-    INTERP.with(|interp_ref| {
-        let interp = interp_ref.borrow();
-        let interp = interp
-            .as_ref()
-            .expect("PyLong_AsLong called before Py_InitializeEx");
-
-        interp.enter(|_vm| {
-            // SAFETY: non-null checked above; caller promises a valid PyObject pointer.
-            let obj_ref = unsafe { &*obj };
-            let int_obj = obj_ref
-                .downcast_ref::<PyInt>()
-                .expect("PyLong_AsLong currently only accepts int instances");
+    with_vm(|_vm| {
+        // SAFETY: non-null checked above; caller promises a valid PyObject pointer.
+        let obj_ref = unsafe { &*obj };
+        let int_obj = obj_ref
+            .downcast_ref::<PyInt>()
+            .expect("PyLong_AsLong currently only accepts int instances");
 
-            int_obj
-                .as_bigint()
-                .try_into()
-                .expect("PyLong_AsLong: value out of range for c_long")
-        })
+        int_obj
+            .as_bigint()
+            .try_into()
+            .expect("PyLong_AsLong: value out of range for c_long")
     })
 }
diff --git a/crates/capi/src/pylifecycle.rs b/crates/capi/src/pylifecycle.rs
@@ -1,12 +1,21 @@
 use core::ffi::c_int;
 use rustpython_vm::Interpreter;
+use rustpython_vm::VirtualMachine;
 use std::cell::RefCell;
 use std::mem::ManuallyDrop;
 
 thread_local! {
     pub static INTERP: RefCell<Option<ManuallyDrop<Interpreter>>> = const { RefCell::new(None) };
 }
 
+pub(crate) fn with_vm<R>(f: impl FnOnce(&VirtualMachine) -> R) -> R {
+    INTERP.with(|interp_ref| {
+        let interp = interp_ref.borrow();
+        let interp = interp.as_ref().expect("VM access before Py_InitializeEx");
+        interp.enter(f)
+    })
+}
+
 #[unsafe(no_mangle)]
 pub extern "C" fn Py_IsInitialized() -> c_int {
     INTERP.with(|interp| interp.borrow().is_some() as c_int)

diff --git a/crates/capi/src/unicodeobject.rs b/crates/capi/src/unicodeobject.rs
@@ -4,7 +4,7 @@ use core::slice;
 use core::str;
 
 use crate::PyObject;
-use crate::pylifecycle::INTERP;
+use crate::pylifecycle::with_vm;
 use rustpython_vm::PyObjectRef;
 
 #[unsafe(no_mangle)]
@@ -21,16 +21,9 @@ pub extern "C" fn PyUnicode_FromStringAndSize(s: *const c_char, len: isize) -> *
         str::from_utf8(bytes).expect("PyUnicode_FromStringAndSize got non-UTF8 data")
     };
 
-    INTERP.with(|interp_ref| {
-        let interp = interp_ref.borrow();
-        let interp = interp
-            .as_ref()
-            .expect("PyUnicode_FromStringAndSize called before Py_InitializeEx");
-
-        interp.enter(|vm| {
-            let obj: PyObjectRef = vm.ctx.new_str(text).into();
-            obj.into_raw().as_ptr()
-        })
+    with_vm(|vm| {
+        let obj: PyObjectRef = vm.ctx.new_str(text).into();
+        obj.into_raw().as_ptr()
     })
 }