Fix #3339: Disallow accesses to private package members from nested pkgs #3735
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
…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
requested changes
Jan 3, 2018
| @@ -733,7 +730,9 @@ object SymDenotations { | |||
| ( !(this is Local) | |||
| || (owner is ImplClass) // allow private local accesses to impl class members | |||
| || isCorrectThisType(pre) | |||
| ) | |||
| ) && | |||
There was a problem hiding this comment.
This long chain of conditions is getting really hard to read, factor it out into a few vals?
There was a problem hiding this comment.
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.
smarter
approved these changes
Jan 4, 2018
odersky
added a commit
to dotty-staging/dotty
that referenced
this pull request
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
added a commit
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.
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Change of the accessibility rules: Disallow accesses to private package members from nested packages.
Such accesses were causing an access error at runtime before.