Harden IDE: Catch NoSuchFileException #4002
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A NoSuchFileException was observed for a non-existing directory on the classpath:
/Users/odersky/workspace/dotty/compiler/../out/bootstrap/dotty-compiler-bootstrapped/scala-0.7/classes
It was after a dotty-bootstrapped/clean. I believe this should be ignored, or maybe handled with
an error message. But certainly not a crash.
| }) | ||
| }) | ||
| catch { | ||
| case _: NoSuchFileException => |
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We should emit an error or warning. If we don't add it in this PR we might have silent failures that are impossible to debug.
| if name.endsWith(tastySuffix) | ||
| } { | ||
| names += root.relativize(path).toString.replace("/", ".").stripSuffix(tastySuffix) | ||
| try |
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if (Files.exists(root)) ... instead of catching an exception?
|
The standard behavior is to (silently) ignore non-existent entries in a classpath. Both scalac and the JVM do that, and historically I can tell you that people rely on this behavior because we had a bug report in Scala.js reporting that we did not ignore them: scala-js/scala-js#2198 |
odersky
dismissed
nicolasstucki’s stale review
Is contradicted by @sjrd's comment
Paths can contain non-tree elements. I observed a path that contained an untpd.Mod instead of a tree. Also, we should survive possible cyclic references when ccomputing the context of a path. (this was also observed in the wild but I can't reproduce it).
| @@ -344,7 +344,7 @@ object Interactive { | |||
| if (tree.pos.contains(pos)) { | |||
| // FIXME: We shouldn't need a cast. Change NavigateAST.pathTo to return a List of Tree? | |||
| val path = NavigateAST.pathTo(pos, tree, skipZeroExtent = true).asInstanceOf[List[untpd.Tree]] | |||
| path.dropWhile(!_.hasType).asInstanceOf[List[tpd.Tree]] | |||
| path.dropWhile(!_.hasType) collect { case t: tpd.Tree @unchecked => t } | |||
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If path can contain non-tree elements then hasType will also throws. Maybe change NavigateAST.pathTo to discard non-tree element and return a List[Tree] instead (as suggested in the comment).
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I made the change on the other PR #3967
A NoSuchFileException was observed for a non-existing directory on the classpath:
It was after a dotty-bootstrapped/clean. I believe this should be ignored, or maybe handled with
an error message. But certainly not a crash.