Trees after typer losing information #15750
Description
Compiler version
3.1.3
Minimized code
object Main {
def foo: ArrayBuffer[Int] = ???
}ArrayBuffer is missing from imports.
Output
Parser tree
PackageDef(
pid = Ident(name = <empty>),
stats = List(
ModuleDef(
name = Main,
impl = Template(
constr = DefDef(
name = <init>,
paramss = List(),
tpt = TypeTree,
preRhs = Thicket(trees = List())
),
parentsOrDerived = List(),
self = ValDef(name = _, tpt = Thicket(trees = List()), preRhs = Thicket(trees = List())),
preBody = List(
DefDef(
name = foo,
paramss = List(),
tpt = AppliedTypeTree(tpt = Ident(name = ArrayBuffer), args = List(Ident(name = Int))),
preRhs = Ident(name = ???)
)
)
)
)
)
)Notice tpt = AppliedTypeTree(tpt = Ident(name = ArrayBuffer), args = List(Ident(name = Int))), <- AppliedTypeTree is available.
Typed tree though:
tree = TypeDef(
name = Main$,
rhs = Template(
constr = DefDef(
name = <init>,
paramss = List(List()),
tpt = TypeTree[TypeRef(ThisType(TypeRef(NoPrefix,module class scala)),class Unit)],
preRhs = Thicket(trees = List())
),
parentsOrDerived = List(
Apply(
fun = Select(
qualifier = New(
tpt = TypeTree[TypeRef(ThisType(TypeRef(NoPrefix,module class lang)),class Object)]
),
name = <init>
),
args = List()
)
),
self = ValDef(
name = _,
tpt = SingletonTypeTree(ref = Ident(name = Main)),
preRhs = Thicket(trees = List())
),
preBody = List(
DefDef(
name = foo,
paramss = List(),
tpt = Ident(name = ArrayBuffer),
preRhs = Ident(name = ???)
)
)
)
),Notice that the tpt of the DefDef is tpt = Ident(name = ArrayBuffer),
Seems that if the type is not available then we are missing TypeApply, which is useful for the IDE to figure out if we need to insert []
Expectation
TypeApply should still be available in tpt of DefDef. It might be an error type, but it should be available there.