Reviewing files that changed from the base of the PR and between 5f496c9 and c5abc44.

• crates/vm/src/builtins/bytes.rs (1 hunks)
• crates/vm/src/builtins/set.rs (1 hunks)
• crates/vm/src/builtins/str.rs (1 hunks)
• crates/vm/src/builtins/tuple.rs (1 hunks)
• crates/vm/src/bytes_inner.rs (1 hunks)
• crates/vm/src/protocol/object.rs (2 hunks)

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

3-7: LGTM - Import cleanup aligns with removed functionality.

The import changes (removing identifier, PyTypeRef, and simplifying pystr import) are consistent with the removal of the get_bytes() method that previously depended on these. The remaining imports support the get_bytearray_inner() method which is still used by the bytes constructor.

crates/vm/src/builtins/str.rs (2)

353-366: LGTM - Optimization for exact str type is correct.

The early return optimization correctly:

1. Checks for exact str type (not subclasses)
2. Ensures single positional argument with no kwargs
3. Verifies the argument is already an exact str

This matches CPython's behavior and avoids unnecessary string copying.

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368-386: LGTM - Clean separation of payload creation logic.

The py_new helper correctly handles all construction cases:

• Decoding with encoding parameter
• Converting via str() without encoding
• Empty string for missing input

The separation from slot_new improves code clarity and follows the pattern established in other builtins.

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

921-958: LGTM - Constructor refactor follows the established pattern.

The implementation correctly:

1. Returns exact frozenset input as-is (line 929-933)
2. Returns empty frozenset singleton for missing iterable (line 936-938)
3. Returns empty frozenset singleton for empty result (line 947-950)
4. Delegates payload creation to py_new which uses from_iter

The type Args = Vec<PyObjectRef> declaration aligns with py_new's signature, while slot_new handles the conversion from FuncArgs to the expected elements vector.

crates/vm/src/protocol/object.rs (2)

7-16: LGTM - Import updates align with new construction pathway.

The import changes correctly add:

• FuncArgs for constructing function arguments
• Constructor trait for invoking the slot_new pathway

These support the refactored bytes() method below.

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34-43: LGTM - Cleaner construction pathway via Constructor trait.

The refactored bytes() method correctly:

1. Maintains the PyInt error handling (bytes shouldn't accept int directly via this path)
2. Creates FuncArgs from the single object argument
3. Delegates to PyBytes::slot_new which handles all construction logic including __bytes__ method invocation and optimizations

This centralizes the bytes construction logic and eliminates the now-removed get_bytes() pathway.

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

112-152: LGTM - Constructor follows the unified pattern across builtins.

The implementation correctly handles all optimization cases:

1. Returns exact input tuple as-is (lines 121-125)
2. Returns empty tuple singleton for missing iterable (lines 128-130)
3. Returns empty tuple singleton for empty result (lines 139-142)
4. Properly separates slot binding (slot_new) from payload creation (py_new)

The type Args = Vec<PyObjectRef> with py_new accepting elements: Self::Args provides a clean interface while slot_new handles the FuncArgs to Vec conversion.

crates/vm/src/builtins/bytes.rs (2)

94-118: Constructor optimizations look correct and consistent with other builtin types.

The optimization pattern correctly mirrors other builtin constructors (tuple, str, float):

• Empty singleton returned for exact type with no arguments
• Exact input bytes returned as-is when no encoding/errors specified
• Use of downcast_exact properly ensures only exact PyBytes instances bypass construction

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139-153: Fallback path and simplified py_new look good.

The structure cleanly separates concerns:

• slot_new handles all optimization logic and protocol dispatch
• py_new is reduced to simple construction from Vec<u8>
• Empty singleton optimization in the fallback path matches the pattern in tuple.rs