script: Restrict scope of mutable borrow in IDBTransaction::ObjectStore.#40139
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jdm merged 1 commit intoservo:mainfrom Oct 25, 2025
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script: Restrict scope of mutable borrow in IDBTransaction::ObjectStore.#40139jdm merged 1 commit intoservo:mainfrom
jdm merged 1 commit intoservo:mainfrom
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Signed-off-by: Josh Matthews <[email protected]>
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| return Ok(DomRoot::from_ref(&*store)); | ||
| } | ||
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| Ok(DomRoot::from_ref(&*store)) |
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I don't know why this was never caught by Lint tho...
Only difference is that here we have a &mut Dom<IDBObjectStore>.
It is better to Ok(DomRoot::from_ref(store)) as well.
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I guess the only reason is to downcast from &mut to &, although unnecessary when passing as arg.
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| ); | ||
| self.store_handles | ||
| .borrow_mut() | ||
| .insert(name.to_string(), Dom::from_ref(&*store)); |
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Now I am confused after #40155 (comment): what happens if store also get GCed before inserting?
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storewon't be GCed because it is rootedIDBObjectStore::newcan trigger GC. GC here means tracing to check what can be collected, so my previous comment certainly make no sense as it is rooted.- The problem was the tracing would also try to mutably borrow the
RefCellresulting in hazards.
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This avoids a borrow hazard when we create a new IDBObjectStore object and that triggers a GC.
Testing: Many IndexedDB tests no longer crash when using a debug mozjs build and full GC zeal. This configuration is not run in CI.
Fixes: #39946