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Reviewing files that changed from the base of the PR and between 7c3bc5e and ebbbb4f.

• crates/stdlib/src/ssl/error.rs
• crates/vm/src/builtins/descriptor.rs
• crates/vm/src/builtins/str.rs
• crates/vm/src/builtins/weakproxy.rs
• crates/vm/src/class.rs
• crates/vm/src/exception_group.rs
• crates/vm/src/exceptions.rs
• crates/vm/src/stdlib/io.rs
• crates/vm/src/stdlib/winreg.rs
• crates/vm/src/types/slot.rs

• crates/vm/src/types/slot.rs

• GitHub Check: Run snippets and cpython tests (windows-latest)

crates/vm/src/class.rs (1)

177-189: repr slot wrapper wiring is consistent with existing slot wrappers

The new __repr__ wrapper follows the same pattern as __init__ / __hash__: it only installs a PySlotWrapper when a repr slot exists and __repr__ is not already present in the type dict, and correctly uses SlotFunc::Repr. This is a clean, minimal integration with the new stringification slot.

crates/vm/src/stdlib/io.rs (1)

1468-1475: More robust formatting of argument-binding errors in BufferedMixin::slot_init

Using e.__str__(vm) with a safe fallback to "<error getting exception str>" keeps the existing error shape ("CLASS_NAME() <msg>") while avoiding failures during stringification. The mapped exception class via e.class() is preserved, so behavior is consistent and safer.

crates/stdlib/src/ssl/error.rs (1)

8-9: PySSLError::str correctly migrated to &Py / PyStrRef

The new signature matches the project-wide pattern (&Py<PyBaseException> -> PyResult<PyStrRef>), and the body still:

• Prefers a non-None strerror attribute (OSError-compatible),
• Falls back to str(args[0]) or str(args).

No behavior regressions are apparent; this aligns with the core exception stringification helpers.

Also applies to: 45-61

crates/vm/src/builtins/descriptor.rs (1)

10-11: Repr slot integration via SlotFunc::Repr is well-structured

• Importing StringifyFunc and adding SlotFunc::Repr(StringifyFunc) cleanly extends the existing slot abstraction.
• SlotFunc::call validates that __repr__ receives no extra args (bound vs unbound) and forwards to the underlying stringify function, returning the resulting PyStrRef as a Python object, mirroring the Hash case.
• The Debug impl is kept up to date.

This should make the new __repr__ slot wrappers behave exactly like native Python methods.

Also applies to: 398-402, 405-410, 414-441

crates/vm/src/builtins/weakproxy.rs (1)

81-84: PyWeakProxy::str updated to new receiver style without changing behavior

Switching to fn __str__(zelf: &Py<Self>, vm: &VirtualMachine) -> PyResult<PyStrRef> and delegating with zelf.try_upgrade(vm)?.str(vm) aligns with the new Py<Self>-based convention while preserving existing semantics for live and dead proxies.

crates/vm/src/exception_group.rs (1)

185-203: BaseExceptionGroup::str correctly migrated to PyStrRef with preserved semantics

The new __str__:

• Safely stringifies arg[0] via .str(vm) with a default empty message,
• Counts sub-exceptions from arg[1] when it’s a PyTuple,
• Produces "message (N sub-exception[s])" as a PyStrRef via vm.ctx.new_str.

This matches the intended ExceptionGroup string representation while conforming to the new &Py<PyBaseException> / PyStrRef pattern.

crates/vm/src/stdlib/winreg.rs (1)

12-12: PyHkey stringification and PyStr usage look good; double‑check HKEY/{:p} compatibility

• The new __str__ signature (fn __str__(zelf: &Py<Self>, vm: &VirtualMachine) -> PyResult<PyRef<PyStr>>) and body (vm.ctx.new_str(format!("<PyHkey:{:p}>", zelf.hkey.load()))) are consistent with the rest of the VM’s __str__ changes and produce the expected textual handle representation.
• The py2reg updates to use PyStr in downcasts (downcast::<PyStr>(), downcast_ref::<PyStr>()) are straightforward and match the new import, with no behavior change.

One thing to verify: depending on the windows-sys version in use, Registry::HKEY may be an isize rather than a raw pointer type. In that case, format!("<PyHkey:{:p}>", zelf.hkey.load()) would fail to compile because {:p} requires a pointer. If you do run into a Pointer-trait compile error, consider either:

• Casting to a raw pointer (e.g., zelf.hkey.load() as *mut core::ffi::c_void), or
• Formatting as a hex integer instead (e.g., "0x{:x}" with as usize).

Also applies to: 236-238, 1032-1035, 1050-1052

crates/vm/src/builtins/str.rs (1)

1452-1460: LGTM!

The signature change from self to zelf: &Py<Self> and the PyResult<PyStrRef> return type aligns well with the broader refactor pattern across this PR. The logic correctly distinguishes between exact str types (returning self) and subclasses (constructing a new exact PyStr), which is the expected Python behavior.

crates/vm/src/exceptions.rs (8)

562-636: LGTM!

Adding Py to the with(...) clause correctly enables the separate impl Py<PyBaseException> block pattern, which is required for the new __str__ signature using the &Py<Self> receiver.

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638-649: LGTM!

The new impl Py<PyBaseException> block correctly implements __str__ with the &self receiver pattern. The logic properly handles the three cases: empty args (empty string), single arg (direct string), and multiple args (tuple-like format). This provides a clean base implementation that subclasses can delegate to.

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1533-1543: LGTM!

The PyKeyError::__str__ correctly maintains its special behavior (using repr for single-key errors) while properly delegating to the base __str__ implementation for other cases. The ? operator correctly propagates any errors from the base method.

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1737-1826: LGTM!

The PyOSError::__str__ implementation correctly handles all the complex formatting cases for OS errors (errno, strerror, filenames, Windows winerror) while properly delegating to the base __str__ as a fallback. The attribute access via zelf.as_object() is consistent with the new receiver pattern.

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2032-2076: LGTM!

The PySyntaxError::__str__ correctly formats syntax error messages with optional filename and line number information, falling back to the base __str__ implementation when the args format doesn't match expectations.

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2184-2210: LGTM!

The PyUnicodeDecodeError::__str__ correctly formats decode error messages with encoding, byte position, and reason. The early return for missing object attribute is a sensible defensive measure.

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2241-2268: LGTM!

The PyUnicodeEncodeError::__str__ correctly formats encode error messages, using UnicodeEscapeCodepoint for proper character escape display. The implementation mirrors the decode error pattern appropriately.

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2298-2323: LGTM!

The PyUnicodeTranslateError::__str__ correctly formats translate error messages. Unlike encode/decode errors, translate errors don't have an encoding field, which is properly reflected in the message format.