Fix #9392: Allow overriding a Java method when a same-named field is present #9452
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…d is present In scala#9126, Java fields were marked effectively finals to prevent false overrides. This poses a problem when a Java field and method of the same name are present, because a Scala val or def will match both of these according to Denotation#matches. This commit changes `matches` to prevent Java field from matching any Scala method, but we can't prevent them from matching Scala definitions with NotAMethod signature without introducing more complexity, so the following still doesn't compile unlike Scala 2: ```java package pkg; public class J { int i = 0; public int i() { return 1; } } ``` ```scala class S2 extends pkg.J { override def i: Int = 2 // error } ``` I have an alternative fix at scala#9412 which doesn't have this issue but is more hacky.
odersky
approved these changes
Aug 3, 2020
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In #9126, Java fields were marked effectively finals to prevent false
overrides. This poses a problem when a Java field and method of the same
name are present, because a Scala val or def will match both of these
according to Denotation#matches. This commit changes
matchestoprevent Java field from matching any Scala method, but we can't prevent
them from matching Scala definitions with NotAMethod signature without
introducing more complexity, so the following still doesn't compile
unlike Scala 2:
I have an alternative fix at #9412 which doesn't have this issue but is
more hacky.