Remove text_signature derive parameter

Drop the string override on #[pyfunction] and #[pyclass]. Signatures are generated from the Rust parameter list only. Restore inspect expectedFailures that depended on the override. Assisted-by: Grok:grok-4.6
youknowone · Sep 24, 2026 · Sep 22, 2026 · Sep 21, 2026 · Sep 21, 2026 · Sep 22, 2026
commit c7b6022bd35826feddedb5e44b3ba87848398ca9
diff --git a/Lib/test/test_functools.py b/Lib/test/test_functools.py
@@ -1238,6 +1238,10 @@ class TestCmpToKeyC(TestCmpToKey, unittest.TestCase):
     if c_functools:
         cmp_to_key = c_functools.cmp_to_key
 
+    @unittest.expectedFailure  # TODO: RUSTPYTHON; inspect.signature reports (args, /) until FromArgs fields generate __text_signature__
+    def test_cmp_to_signature(self):
+        super().test_cmp_to_signature()
+
     @support.cpython_only
     def test_disallow_instantiation(self):
         # Ensure that the type disallows instantiation (bpo-43916)

diff --git a/Lib/test/test_inspect/test_inspect.py b/Lib/test/test_inspect/test_inspect.py
@@ -1363,6 +1363,7 @@ def test(): pass
         spec = inspect.getfullargspec(test)
         self.assertEqual(test.__annotations__, spec.annotations)
 
+    @unittest.expectedFailure  # TODO: RUSTPYTHON; os.stat signature is generated as (path, dir_fd, follow_symlinks, /)
     @unittest.skipIf(MISSING_C_DOCSTRINGS,
                      "Signature information for builtins requires docstrings")
     def test_getfullargspec_builtin_methods(self):
@@ -3511,6 +3512,7 @@ def m1d(*args, **kwargs):
                            ('arg2', 1, ..., "positional_or_keyword")),
                           int))
 
+    @unittest.expectedFailure  # TODO: RUSTPYTHON; ValueError: no signature found for builtin type <class 'classmethod'>
     def test_signature_on_classmethod(self):
         if not support.MISSING_C_DOCSTRINGS:
             self.assertEqual(self.signature(classmethod),
@@ -3534,6 +3536,7 @@ def foo(cls, arg1, *, arg2=1):
                            ('arg2', 1, ..., "keyword_only")),
                           ...))
 
+    @unittest.expectedFailure  # TODO: RUSTPYTHON; ValueError: no signature found for builtin type <class 'staticmethod'>
     def test_signature_on_staticmethod(self):
         if not support.MISSING_C_DOCSTRINGS:
             self.assertEqual(self.signature(staticmethod),
@@ -4612,6 +4615,7 @@ class D(C): pass
         with self.assertRaisesRegex(ValueError, "callable.*is not supported"):
             self.assertEqual(inspect.signature(D), None)
 
+    @unittest.expectedFailure  # TODO: RUSTPYTHON; ValueError: no signature found for builtin type <class '_pickle.Pickler'>
     @unittest.skipIf(MISSING_C_DOCSTRINGS,
                      "Signature information for builtins requires docstrings")
     def test_signature_on_builtin_class(self):
@@ -5153,6 +5157,7 @@ class foo: pass
         foo_sig = MySignature.from_callable(foo)
         self.assertIsInstance(foo_sig, MySignature)
 
+    @unittest.expectedFailure  # TODO: RUSTPYTHON; ValueError: no signature found for builtin type <class '_pickle.Pickler'>
     @unittest.skipIf(MISSING_C_DOCSTRINGS,
                      "Signature information for builtins requires docstrings")
     def test_signature_from_callable_builtin_obj(self):

diff --git a/crates/derive-impl/src/pyclass.rs b/crates/derive-impl/src/pyclass.rs
@@ -434,7 +434,6 @@ fn cpython_attr_doc(rust_type: &str, attr: &str) -> Option<String> {
     None
 }
 
-#[allow(clippy::too_many_arguments)]
 fn generate_class_def(
     ident: &Ident,
     name: &str,
@@ -443,22 +442,13 @@ fn generate_class_def(
     metaclass: Option<String>,
     unhashable: bool,
     attrs: &[Attribute],
-    text_signature: Option<&str>,
 ) -> Result<TokenStream> {
     let doc = attrs.doc().or_else(|| {
         let module_name = module_name.unwrap_or("builtins");
         DB.get(&format!("{module_name}.{name}"))
             .copied()
             .map(str::to_owned)
     });
-    let doc = match (text_signature, doc) {
-        (Some(sig), doc) => Some(format_doc(
-            &format!("{name}{sig}"),
-            &doc.unwrap_or_default(),
-        )),
-        (None, Some(doc)) => Some(doc),
-        (None, None) => None,
-    };
     let doc = if let Some(doc) = doc {
         quote!(Some(#doc))
     } else {
@@ -598,23 +588,21 @@ pub(crate) fn impl_pyclass(attr: PunctuatedNestedMeta, item: Item) -> Result<Tok
     }
 
     let fake_ident = Ident::new("pyclass", item.span());
-    let (class_meta, class_name, module_name, base, metaclass, unhashable, text_signature) = {
+    let (class_meta, class_name, module_name, base, metaclass, unhashable) = {
         let (ident, _) = pyclass_ident_and_attrs(&item)?;
         let class_meta = ClassItemMeta::from_nested(ident.clone(), fake_ident, attr.into_iter())?;
         let class_name = class_meta.class_name()?;
         let module_name = class_meta.module()?;
         let base = class_meta.base()?;
         let metaclass = class_meta.metaclass()?;
         let unhashable = class_meta.unhashable()?;
-        let text_signature = class_meta.text_signature()?;
         (
             class_meta,
             class_name,
             module_name,
             base,
             metaclass,
             unhashable,
-            text_signature,
         )
     };
 
@@ -661,7 +649,6 @@ pub(crate) fn impl_pyclass(attr: PunctuatedNestedMeta, item: Item) -> Result<Tok
         metaclass,
         unhashable,
         attrs,
-        text_signature.as_deref(),
     )?;
 
     const ALLOWED_TRAVERSE_OPTS: &[&str] = &["manual"];

diff --git a/crates/derive-impl/src/pymodule.rs b/crates/derive-impl/src/pymodule.rs
@@ -2,7 +2,7 @@ use crate::error::Diagnostic;
 use crate::pystructseq::PyStructSequenceMeta;
 use crate::util::{
     ALL_ALLOWED_NAMES, AttrItemMeta, AttributeExt, ClassItemMeta, ContentItem, ContentItemInner,
-    ErrorVec, FunctionItemMeta, ItemMeta, ItemNursery, ModuleItemMeta, SimpleItemMeta, format_doc,
+    ErrorVec, ItemMeta, ItemNursery, ModuleItemMeta, SimpleItemMeta, format_doc,
     infer_native_call_flags, iter_use_idents, pyclass_ident_and_attrs, text_signature,
 };
 use core::str::FromStr;
@@ -661,13 +661,10 @@ impl ModuleItem for FunctionItem {
         let ident = &func.sig().ident;
 
         let item_attr = args.attrs.remove(self.index());
-        let item_meta = FunctionItemMeta::from_attr(ident.clone(), &item_attr)?;
+        let item_meta = SimpleItemMeta::from_attr(ident.clone(), &item_attr)?;
 
         let py_name = item_meta.simple_name()?;
-        let sig_doc = match item_meta.text_signature()? {
-            Some(sig) => Some(format!("{py_name}{sig}")),
-            None => text_signature(func.sig(), &py_name, None),
-        };
+        let sig_doc = text_signature(func.sig(), &py_name, None);
 
         let module = args.module_name();
         // TODO: doc must exist at least one of code or CPython

diff --git a/crates/derive-impl/src/util.rs b/crates/derive-impl/src/util.rs
@@ -315,26 +315,6 @@ impl ItemMeta for SimpleItemMeta {
     }
 }
 
-pub(crate) struct FunctionItemMeta(pub ItemMetaInner);
-
-impl ItemMeta for FunctionItemMeta {
-    const ALLOWED_NAMES: &'static [&'static str] = &["name", "text_signature"];
-
-    fn from_inner(inner: ItemMetaInner) -> Self {
-        Self(inner)
-    }
-
-    fn inner(&self) -> &ItemMetaInner {
-        &self.0
-    }
-}
-
-impl FunctionItemMeta {
-    pub(crate) fn text_signature(&self) -> Result<Option<String>> {
-        self.inner()._optional_str("text_signature")
-    }
-}
-
 pub(crate) struct ModuleItemMeta(pub ItemMetaInner);
 
 impl ItemMeta for ModuleItemMeta {
@@ -383,7 +363,6 @@ impl ItemMeta for ClassItemMeta {
         "traverse",
         "clear", // tp_clear
         "payload",
-        "text_signature",
     ];
 
     fn from_inner(inner: ItemMetaInner) -> Self {
@@ -441,10 +420,6 @@ impl ClassItemMeta {
         self.inner()._optional_str("metaclass")
     }
 
-    pub(crate) fn text_signature(&self) -> Result<Option<String>> {
-        self.inner()._optional_str("text_signature")
-    }
-
     pub(crate) fn module(&self) -> Result<Option<String>> {
         const KEY: &str = "module";
         let inner = self.inner();

diff --git a/crates/stdlib/src/pickle.rs b/crates/stdlib/src/pickle.rs
@@ -462,11 +462,7 @@ mod _pickle {
     }
 
     #[pyattr]
-    #[pyclass(
-        module = "_pickle",
-        name = "Unpickler",
-        text_signature = "(file, *, fix_imports=True, encoding='ASCII', errors='strict', buffers=())"
-    )]
+    #[pyclass(module = "_pickle", name = "Unpickler")]
     #[derive(Debug, PyPayload)]
     pub(super) struct PyUnpickler {
         read_state: PyMutex<ReadState>,
@@ -1666,9 +1662,7 @@ mod _pickle {
         })
     }
 
-    #[pyfunction(
-        text_signature = "(data, /, *, fix_imports=True, encoding='ASCII', errors='strict', buffers=())"
-    )]
+    #[pyfunction]
     fn loads(args: LoadsArgs, vm: &VirtualMachine) -> PyResult<PyObjectRef> {
         if args.data.downcastable::<PyStr>() {
             return Err(vm.new_type_error("Can't load pickle from unicode string"));
@@ -1715,9 +1709,7 @@ mod _pickle {
         buffers: OptionalArg<PyObjectRef>,
     }
 
-    #[pyfunction(
-        text_signature = "(file, *, fix_imports=True, encoding='ASCII', errors='strict', buffers=())"
-    )]
+    #[pyfunction]
     fn load(args: LoadArgs, vm: &VirtualMachine) -> PyResult<PyObjectRef> {
         let peek = vm.get_attribute_opt(args.file.clone(), "peek")?;
         let read = vm.get_attribute_opt(args.file.clone(), "read")?;
@@ -1939,11 +1931,7 @@ mod _pickle {
     }
 
     #[pyattr]
-    #[pyclass(
-        module = "_pickle",
-        name = "Pickler",
-        text_signature = "(file, protocol=None, fix_imports=True, buffer_callback=None)"
-    )]
+    #[pyclass(module = "_pickle", name = "Pickler")]
     #[derive(Debug, PyPayload)]
     pub(super) struct PyPickler {
         out: PyMutex<Output>,
@@ -3789,9 +3777,7 @@ mod _pickle {
         buffer_callback: OptionalArg<PyObjectRef>,
     }
 
-    #[pyfunction(
-        text_signature = "(obj, file, protocol=None, *, fix_imports=True, buffer_callback=None)"
-    )]
+    #[pyfunction]
     fn dump(args: DumpArgs, vm: &VirtualMachine) -> PyResult<()> {
         let new_args = PicklerNewArgs {
             file: args.file,
@@ -3831,9 +3817,7 @@ mod _pickle {
         buffer_callback: OptionalArg<PyObjectRef>,
     }
 
-    #[pyfunction(
-        text_signature = "(obj, protocol=None, *, fix_imports=True, buffer_callback=None)"
-    )]
+    #[pyfunction]
     fn dumps(args: DumpsArgs, vm: &VirtualMachine) -> PyResult<PyObjectRef> {
         let new_args = PicklerNewArgs {
             file: vm.ctx.none(),

diff --git a/crates/vm/src/builtins/classmethod.rs b/crates/vm/src/builtins/classmethod.rs
@@ -29,12 +29,7 @@ use crate::{
 ///
 /// Class methods are different than C++ or Java static methods.
 /// If you want those, see the staticmethod builtin.
-#[pyclass(
-    module = false,
-    name = "classmethod",
-    text_signature = "(function, /)",
-    traverse
-)]
+#[pyclass(module = false, name = "classmethod", traverse)]
 #[derive(Debug)]
 pub struct PyClassMethod {
     callable: PyMutex<PyObjectRef>,

diff --git a/crates/vm/src/builtins/staticmethod.rs b/crates/vm/src/builtins/staticmethod.rs
@@ -12,12 +12,7 @@ use crate::{
     types::{Callable, Constructor, GetDescriptor, Initializer, Representable},
 };
 
-#[pyclass(
-    module = false,
-    name = "staticmethod",
-    text_signature = "(function, /)",
-    traverse
-)]
+#[pyclass(module = false, name = "staticmethod", traverse)]
 #[derive(Debug)]
 pub struct PyStaticMethod {
     pub callable: PyMutex<PyObjectRef>,

diff --git a/crates/vm/src/stdlib/_functools.rs b/crates/vm/src/stdlib/_functools.rs
@@ -67,7 +67,7 @@ mod _functools {
         mycmp: PyObjectRef,
     }
 
-    #[pyfunction(text_signature = "(mycmp)")]
+    #[pyfunction]
     fn cmp_to_key(args: CmpToKeyArgs) -> PyKeyWrapper {
         PyKeyWrapper {
             cmp: args.mycmp,

diff --git a/crates/vm/src/stdlib/os.rs b/crates/vm/src/stdlib/os.rs
@@ -1457,7 +1457,7 @@ pub(super) mod _os {
         }
     }
 
-    #[pyfunction(text_signature = "(path, *, dir_fd=None, follow_symlinks=True)")]
+    #[pyfunction]
     #[pyfunction(name = "fstat")]
     fn stat(
         path: OsPathOrFd<'_>,
@@ -1474,7 +1474,7 @@ pub(super) mod _os {
         Ok(StatResultData::from_stat(&stat, vm).to_pyobject(vm))
     }
 
-    #[pyfunction(text_signature = "(path, *, dir_fd=None)")]
+    #[pyfunction]
     fn lstat(
         path: OsPath,
         dir_fd: DirFd<'_, { STAT_DIR_FD as usize }>,