Fix #18484: Query every legal child of sealed class on children call #18561
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| if !is(Enum) then // non-enum sealed class | ||
| // Make sure all children are completed, so that | ||
| // they show up in Child annotations. | ||
| completeChildrenIn(defn.RootClass, recursively = true) |
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I spent some time trying to find something smarter than just starting at the <root> package - but neither Symbol.topLevelClass nor Symbol.enclosingPackageClass really helped. If some kind of method that returns packages/classes for a source file there already exists in the compiler, it is probably more performant than this (but I could not find anything like that).
…call Sometimes, a macro or Mirror can be called/generated for a type that may have not had its children registered by natural typechecking procedures of the compiler. This meant that, in those cases, the Mirror could not have been generated correctly, and macro could not obtain the children of the class. This was partially fixed in a previous PR by introducing a separate procedure for querying children, outside of the regular typechecking procedure. However, they was only queried in the owner symbol or in the companion class, when non-enum sealed classes specifically, can appear anywhere in the file. This commit aims to rectify this by searching for any class that appears in the same file as the sealed type.
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Apparently, the previous behavior is (or should be made) part of the spec. Even barring the inefficiency of the presented fix, apparently completing children in various corner case situations was a constant problem in Scala 2, thus the more limiting, clear and transparent rule presented in the previous error message (as in, the fact that it asks you to keep all of the children on the same nesting level) might make things more consistent. |
Sometimes, a macro or Mirror can be called/generated for a type that may have not had its children registered by the natural typechecking procedures of the compiler. This meant that, in those cases, the Mirror could not have been generated correctly, and macro could not have obtained the children of the class.
This was partially fixed in a previous PR by introducing a separate procedure for querying children, outside of the regular typechecking procedure. However, the children were only queried for in the owner symbol or in the companion class, whereas non-enum sealed classes specifically, can appear anywhere in the file. This commit aims to rectify this by searching for any class that appears in the same file as the sealed class.
Fixes #18484
I made the test case here a bit more robust than in the issue to better test the changes.