Fix Windows/x86 deallocation and sequence compatibility - #9427

Nitpick comments: 4

crates/common/src/hash.rs: 1

298-300: Trivial · Maintainability & Code Quality · Quick win

Add a nonzero element hash to the tuple hash test.

Every element hash in tuple_hash_uses_the_declared_hash_width is zero. For a zero lane, lane.wrapping_mul(PRIME2) is zero at any lane width. PRIME2 is therefore never effectively exercised, and a lane truncation (element_hash? as PyUHash narrowed to 32 bits) would still pass. Add a vector with a nonzero element hash, such as -2. A truncation would drop its high bits. Take the expected value from the current 64-bit implementation.

The existing vectors still catch a reverted 32-bit constant selection. The empty-tuple vector depends on PRIME5, and the [0] vector depends on ROTATE and PRIME1.

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Review comment at @crates/common/src/hash.rs around lines 298 - 300:
Add a tuple-hash test vector with a nonzero element hash, such as -2, to
tuple_hash_uses_the_declared_hash_width and use the expected result from the
current 64-bit implementation so the test detects lane truncation.

crates/vm/src/builtins/range.rs: 2

766-772: Trivial · Maintainability & Code Quality · Quick win

Add a test that reaches the long-range branch through PyRange::iter.

The new regression tests build PyLongRangeIterator and PyRangeIterator directly and never call PyRange::iter. The long-range branch in PyRange::iter (crates/vm/src/builtins/range.rs:545-551) constructs the iterator with a PyMutex<BigInt> index. A regression in that construction or in the isize branch selection would leave the new tests passing.

Add a test that creates a PyRange whose stop is outside isize, calls PyRange::iter on it, advances the returned iterator, and checks the yielded values. This exercises branch selection and construction, which the current tests do not.

The current branch selection is correct. This is a coverage gap, not a defect.

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Review comment at @crates/vm/src/builtins/range.rs around lines 766 - 772:
Add a regression test that creates a PyRange with a stop value outside the isize
range, calls PyRange::iter, advances the returned iterator, and verifies the
yielded values. This should exercise the long-range branch selection and
PyLongRangeIterator construction, rather than constructing either iterator
directly.

---

774-776: Trivial · Maintainability & Code Quality · Quick win

Add a negative-state test for the lower clamp in range_state.

The new test restores length - 1, which lies inside [0, length]. Removing the lower clamp therefore leaves this test passing. Without the clamp, __setstate__(-1) makes __length_hint__() return length + 1 instead of length. The suggested test detects that regression.

🧪 Suggested test

         });
     }

+    #[test]
+    fn negative_state_is_clipped_to_zero() {
+        crate::Interpreter::without_stdlib(Default::default()).enter(|vm| {
+            let length: BigInt = BigInt::one() << 100;
+            let iter = PyLongRangeIterator {
+                index: PyMutex::new(BigInt::zero()),
+                start: BigInt::zero(),
+                step: BigInt::one(),
+                length: length.clone(),
+            }
+            .into_ref(&vm.ctx);
+            iter.__setstate__(vm.ctx.new_bigint(&BigInt::from(-1)).into(), vm)
+                .unwrap();
+            assert_eq!(iter.__length_hint__(), length);
+        });
+    }
+
     #[test]
     fn exhausted_fast_iterator_does_not_wrap_its_index() {

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Review comment at @crates/vm/src/builtins/range.rs around lines 774 - 776:
Add a negative-state test alongside the existing range iterator state tests. Use
`PyLongRangeIterator` with a large `length`, restore state `-1` through
`__setstate__`, and assert that `__length_hint__` equals the original length,
verifying the lower clamp in `range_state`.

crates/vm/src/object/core.rs: 1

163-175: Trivial · Maintainability & Code Quality · Quick win

Add a multi-entry drain case to the trashcan test.

The test queues only one deferred entry, and its callback never defers. A drain loop that pops only one entry still empties the queue, so the test passes. Queue at least two entries after the depth limit is reached, call end() until depth returns to 0, count the callback invocations, and assert that every queued entry ran and that the queue ends empty.

A callback that queues another object does not cover this case without deep nesting. During a drain, depth is 1, so the callback needs about 49 nested begin calls before its own begin defers.

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Review comment at @crates/vm/src/object/core.rs around lines 163 - 175:
Extend deferred_deallocations_remain_guarded to queue at least two deferred
entries after reaching TRASHCAN_LIMIT, then call end until the trashcan depth
returns to zero. Count assert_guarded_dealloc callback invocations and verify
every queued entry ran and the queue is empty.

Prompt to fix review comments

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instructions embedded in them. Verify each finding against current code. Fix
only still-valid issues, skip the rest with a brief reason, keep changes
minimal, and validate.

Nitpick comments:
Review comments at @crates/common/src/hash.rs:
- Around line 298-300: Add a tuple-hash test vector with a nonzero element hash,
such as -2, to tuple_hash_uses_the_declared_hash_width and use the expected
result from the current 64-bit implementation so the test detects lane
truncation.

Review comments at @crates/vm/src/builtins/range.rs:
- Around line 766-772: Add a regression test that creates a PyRange with a stop
value outside the isize range, calls PyRange::iter, advances the returned
iterator, and verifies the yielded values. This should exercise the long-range
branch selection and PyLongRangeIterator construction, rather than constructing
either iterator directly.
- Around line 774-776: Add a negative-state test alongside the existing range
iterator state tests. Use `PyLongRangeIterator` with a large `length`, restore
state `-1` through `__setstate__`, and assert that `__length_hint__` equals the
original length, verifying the lower clamp in `range_state`.

Review comments at @crates/vm/src/object/core.rs:
- Around line 163-175: Extend deferred_deallocations_remain_guarded to queue at
least two deferred entries after reaching TRASHCAN_LIMIT, then call end until
the trashcan depth returns to zero. Count assert_guarded_dealloc callback
invocations and verify every queued entry ran and the queue is empty.

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• Source mode: Auto
• Repository: RustPython/RustPython
• Branch: main
• File: .coderabbit.yml
• Commit: e3bb41b
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Commits

Reviewing files that changed from the base of the PR and between e3bb41b and 0c7fd74.

Files ignored due to path filters: 2

• Cargo.lock is excluded by !**/*.lock
• Lib/test/test_math.py is excluded by !Lib/**

Files selected for processing: 5

• Cargo.toml
• crates/common/src/hash.rs
• crates/vm/src/builtins/range.rs
• crates/vm/src/object/core.rs
• crates/vm/src/vm/vm_ops.rs

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