safety violation fix: RefCell::unwrap #15952
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The `unwrap` method for `RefCell` was using `debug_assert!` to check that the `RefCell` was not aleady borrowed before unwrapping. However, disabling this assertion can lead to safety violations. This commit changes the code to fail explicitly with a useful message, similarly to the `borrow` and `borrow_mut` methods.
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flip1995
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Nov 28, 2025
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The
unwrapmethod forRefCellwas usingdebug_assert!to checkthat the
RefCellwas not aleady borrowed before unwrapping. However,disabling this assertion can lead to safety violations.
This commit changes the code to fail explicitly with a useful message,
similarly to the
borrowandborrow_mutmethods.