Fix #6460: less forcing in checkNonCyclic #6493
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| final def moduleClass(implicit ctx: Context): Symbol = { | ||
| def notFound = { | ||
| if (Config.showCompletions) println(s"missing module class for $name: $myInfo") | ||
| NoSymbol | ||
| } | ||
| if (this is ModuleVal) | ||
| if (this is ModuleClass) |
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For speed I'd move the operations that return the same symbol towards the end, i.e. where otherwise NoSymbol would be returned.
| * otherwise NoSymbol | ||
| */ | ||
| final def sourceModule(implicit ctx: Context): Symbol = | ||
| if (this is ModuleVal) |
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This is more intuitive in my opinion. As a side-effect, this makes the logic for creating stub package symbols in `staticRef` more robust which broke the `missingDottyLib` test. This is fixed by moving the `isPackageFromCoreLibMissing` check earlier.
checkNonCyclic was forcing too many infos because it didn't account for the case where the prefix is a ModuleVal and not a ModuleClass. Fixing this solves the incremental compilation issue in the Dotty build reported in scala#6460 were the root cause was a completion cycle when jointly compiling SymbolLoaders and Types that looked like this: Complete `object tpd` Complete its parent `Trees.Instance` Complete its type parameter `T >: Untyped <: Type` run `checkNonCyclic` on the the type parameter definition Complete `Type` Complete `import ast.tpd._` in `Types.scala` Eventually this requires unpickling the selection `Trees.Instance#T` which gets a `NoDenotation` since `T` hasn't been entered yet. As a side-effect this also means that the neg/toplevel-cyclic test no longer leads to an "illegal cyclic reference" error, instead it now causes "recursion limit exceeded" errors, which are less nice but still acceptable.
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checkNonCyclic was forcing too many infos because it didn't account for
the case where the prefix is a ModuleVal and not a ModuleClass. Fixing
this solves the incremental compilation issue in the Dotty build
reported in #6460 were the root cause was a completion cycle when
jointly compiling SymbolLoaders and Types that looked like this:
Complete
object tpdComplete its parent
Trees.InstanceComplete its type parameter
T >: Untyped <: Typerun
checkNonCyclicon the the type parameter definitionComplete
TypeComplete
import ast.tpd._inTypes.scalaEventually this requires unpickling the selection
Trees.Instance#Twhichgets a
NoDenotationsinceThasn't been entered yet.As a side-effect this also means that the neg/toplevel-cyclic
test no longer leads to an "illegal cyclic reference" error, instead it
now causes "recursion limit exceeded" errors, which are less nice but
still acceptable.