Fix #3339: Disallow accesses to private package members from nested pkgs #3735
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…ted pkgs Change of the accessibility rules: Disallow accesses to private package members from nested packages. Such accesses were causing an access error at runtime before.
smarter
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Jan 3, 2018
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Otherwise LGTM but a test case is missing.
| || (owner is ImplClass) // allow private local accesses to impl class members | ||
| || isCorrectThisType(pre) | ||
| ) | ||
| ) && |
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This long chain of conditions is getting really hard to read, factor it out into a few vals?
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I tried but it does not seem to help. The key is treating !A || B as an implication, then things get clearer. I was wondering whether we should add an inline helper method implies on Boolean to do this. But it's quite a lot of effort.
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Jan 4, 2018
odersky
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Jan 25, 2019
Test case is i3339. In
```
package outer {
private class A() {
override def toString = "A"
}
package inner {
object Test {
def main(args: Array[String]): Unit = {
println(new A()) // allow access?
}
}
}
}
```
should the access to private class `A` from a nested package be allowed?
The usual rules for Scala say yes, since the access is from a nested scope.
We changed this to in scala#3735 to "no", since we wanted to emulate Java's default
package-private visibility. But this is unsystematic for two reasons:
- it breaks the universal meaning of `private` in Scala
- it uses a different name (i.e. private) for what is not named
in Java at all, and is named `internal` in Kotlin.
- it does not generalize to members of classes which could
also profit from a Java-package-private visibility specifier.
I believe it is better to leave `private` as it is, and, if we want to
emulate `internal` (which might be a good idea), introduce a new modifier
for it.
odersky
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to dotty-staging/dotty
that referenced
this pull request
Feb 1, 2019
Test case is i3339. In
```
package outer {
private class A() {
override def toString = "A"
}
package inner {
object Test {
def main(args: Array[String]): Unit = {
println(new A()) // allow access?
}
}
}
}
```
should the access to private class `A` from a nested package be allowed?
The usual rules for Scala say yes, since the access is from a nested scope.
We changed this to in scala#3735 to "no", since we wanted to emulate Java's default
package-private visibility. But this is unsystematic for two reasons:
- it breaks the universal meaning of `private` in Scala
- it uses a different name (i.e. private) for what is not named
in Java at all, and is named `internal` in Kotlin.
- it does not generalize to members of classes which could
also profit from a Java-package-private visibility specifier.
I believe it is better to leave `private` as it is, and, if we want to
emulate `internal` (which might be a good idea), introduce a new modifier
for it.
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Change of the accessibility rules: Disallow accesses to private package members from nested packages.
Such accesses were causing an access error at runtime before.