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Reviewing files that changed from the base of the PR and between 46c61a6 and 1c0321f.

• crates/vm/src/buffer.rs (4 hunks)
• crates/vm/src/protocol/buffer.rs (1 hunks)
• scripts/fix_test.py (1 hunks)

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

scripts/fix_test.py (1)

162-166: LGTM!

The package test detection logic correctly handles nested test structures. The conditional check for test_ prefix in the parent directory name appropriately distinguishes between package-style and single-file tests.

crates/vm/src/buffer.rs (4)

153-155: LGTM with note on long double representation.

The non-native format mappings are reasonable. Note that LongDouble => f64 is a simplification—actual long double varies by platform (80-bit on x86, 128-bit on some architectures)—but this is consistent with the native mapping approach used elsewhere in the code.

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190-192: LGTM!

The native format mappings correctly use platform-specific types: raw::c_double for LongDouble and *mut raw::c_void for PyObject pointer representation.

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315-326: Verify PEP 3118 compliance for non-standard format characters.

PEP 3118 specifies that endian markers ('!', '@','=','>','<', '^') are allowed inside format strings and can change as needed. The code correctly skips these standard markers (<, >, @, =, !) to allow them mid-string. However, the code also skips & as a "pointer prefix," which is not documented in PEP 3118. The standard format code for pointers is P, not &. Clarify whether & is a custom extension for this implementation beyond PEP 3118, or document what specification it implements.

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91-93: Format codes 'g' (LongDouble) and 'O' (PyObject) align with proposed PEP 3118 but use pragmatic approximations.

While PEP 3118 proposed additions to struct string-syntax, only ? (_Bool) was officially implemented in CPython's struct module. However, NumPy's PEP 3118 parser includes both 'g' and 'O' in its supported format codes. The implementation correctly maps LongDouble to f64 (treating it as double) and PyObject to void* pointers. Verify that these pragmatic approximations—particularly the comment "long double same as double for now"—are appropriate for downstream buffer protocol consumers and document any deviations from full PEP 3118 compliance if this implementation is exposed as a standards-conformant buffer protocol provider.

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

206-210: LGTM!

The relaxed validation correctly handles empty scalar structures (len=0, itemsize=0) while maintaining the invariant itemsize == len for zero-dimensional cases. The conditional check if self.len > 0 appropriately enforces non-zero itemsize only when necessary.

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213-220: LGTM!

The has_zero_dim flag correctly permits zero strides for empty arrays (any dimension is zero) while preserving the stride validation for non-empty arrays. Computing the flag before iteration is efficient, and the final invariant shape_product * itemsize == len (line 222) remains enforced.