Check protected parent constructor accesses only occurs in child constructors#25511
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…tructors Currently, protected parent class constructor calls that occur outside of their subclass constructors are not properly checked. So it possible to call a parent constructor in any method of subclass. This change checks that such accesses only occur inside subclass constructors. This fixes scala#25442.
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bracevac
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lrytz
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| pre.termSymbol.isPackageObject && accessWithin(pre.termSymbol.owner) | ||
| else | ||
| else { | ||
| val isConstructorAccessOK = isConstructor && ctx.owner.isConstructor |
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The following should also be rejected; is it?
class I protected (x: Int) {
protected def f = x
}
class M protected () extends I(42) {
def this(x: Int) = { this(); new I(x) } // error
}
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Right. It should've been ctx.owner.isPrimaryConstructor then.
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Playing with this some more, I think even checking for isPrimaryConstructor is not granular enough:
class A protected (x: Int)
class B protected (a: A) extends A(a.hashCode)
class C extends B(new A(1)) // should be error, but ok currently
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…tructors (scala#25511) Fixes scala#25442. Currently, protected parent class constructor calls that occur outside of their subclass constructors are not properly checked. So it possible to call a parent constructor in any method of subclass. This change checks that such accesses only occur inside subclass constructors. No LLM-based tools were used. negative test case from issue included. Co-authored-by: James You <jyou@protonmail.com> [Cherry-picked 230925d]
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Fixes #25442.
Currently, protected parent class constructor calls that occur outside of their subclass constructors are not properly checked. So it possible to call a parent constructor in any method of subclass. This change checks that such accesses only occur inside subclass constructors.
No LLM-based tools were used.
negative test case from issue included.