[compiler][repro] Postfix operator is incorrectly compiled #33508
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josephsavona
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| export const FIXTURE_ENTRYPOINT = { | ||
| fn: useFoo, | ||
| params: [], | ||
| }; |
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you might be able to get a runnable test (that fails the forget/no-forget comparison) by using effects that setState w the result of the increment
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Just did a console log for now so sprout catches it. I added this fixture to the sprout filter.
This bug was reported via our wg and appears to only affect values created as a ref. Currently, postfix operators used in a callback gets compiled to: ```js modalId.current = modalId.current + 1; // 1 const id = modalId.current; // 1 return id; ``` which is semantically incorrect. The postfix increment operator should return the value before incrementing. In other words something like this should have been compiled instead: ```js const id = modalId.current; // 0 modalId.current = modalId.current + 1; // 1 return id; ``` This bug does not trigger when the incremented value is a plain primitive, instead there is a TODO bailout.
This was referenced Jun 11, 2025
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This bug was reported via our wg and appears to only affect values created as a ref.
Currently, postfix operators used in a callback gets compiled to:
which is semantically incorrect. The postfix increment operator should return the value before incrementing. In other words something like this should have been compiled instead:
This bug does not trigger when the incremented value is a plain primitive, instead there is a TODO bailout.