Don't leak sharpened bounds between implicit candidates#6308
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retronym merged 2 commits intoscala:2.13.xfrom Mar 5, 2018
Merged
Don't leak sharpened bounds between implicit candidates#6308retronym merged 2 commits intoscala:2.13.xfrom
retronym merged 2 commits intoscala:2.13.xfrom
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The bounds propagation introduced in scala#6140 caused a regression in scala/scala-java8-compat#97 because bounds sharpened while ranking implicit candidates leaked from candidates tested earlier to those tested later. This commit fixes that by saving and restoring the infos of the symbols of the undetermined type parameters around the call to type check the implicit candidate which tests for it's applicability. Initially it seemed like this ought to be a job for undoLog or Context#savingUndeteriminedTypeParams, but neither of those do the right thing here. UndoLog doesn't help because it affects the constraint on the corresponding TypeVar rather than the info of the symbol; and savingUndeterminedTypeParams doesn't help because the relevant call to typedImplicit shares the enclosing ImplicitSearch#undetParams rather than looking at the context.
This was referenced Feb 3, 2018
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retronym
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Feb 5, 2018
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| val savedInfos = undetParams.map(_.info) | ||
| val typedFirstPending = typedImplicit(firstPending, ptChecked = true, isLocalToCallsite) | ||
| foreach2(undetParams, savedInfos){ (up, si) => up.setInfo(si) } |
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Let's put this in a try/finally.
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/synch |
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/rebuild |
This was referenced Feb 19, 2018
retronym
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Mar 5, 2018
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The bounds propagation introduced in #6140 caused a regression in scala/scala-java8-compat#97 because bounds sharpened while ranking implicit candidates leaked from candidates tested earlier to those tested later.
This commit fixes that by saving and restoring the infos of the symbols of the undetermined type parameters around the call to type check the implicit candidate which tests for it's applicability.
Initially it seemed like this ought to be a job for
undoLogorContext#savingUndeteriminedTypeParams,but neither of those do the right thing here.UndoLogdoesn't help because it affects the constraint onthe corresponding
TypeVarrather than the info of the symbol; andsavingUndeterminedTypeParamsdoesn't help because the relevant call totypedImplicitshares the enclosingImplicitSearch#undetParamsrather than looking at the context.Fixes scala/bug#10708.