Add reflect AppliedType constructor

Fixes #14740
scala · Apr 14, 2022 · e6100e0 · e6100e0
1 parent bdddd41
commit e6100e0
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Showing 5 changed files with 25 additions and 3 deletions.
diff --git a/compiler/src/scala/quoted/runtime/impl/QuotesImpl.scala b/compiler/src/scala/quoted/runtime/impl/QuotesImpl.scala
@@ -1893,6 +1893,8 @@ class QuotesImpl private (using val ctx: Context) extends Quotes, QuoteUnpickler
     end AppliedTypeTypeTest
 
     object AppliedType extends AppliedTypeModule:
+      def apply(tycon: TypeRepr, args: List[TypeRepr]): AppliedType =
+        Types.AppliedType(tycon, args)
       def unapply(x: AppliedType): (TypeRepr, List[TypeRepr]) =
         (AppliedTypeMethods.tycon(x), AppliedTypeMethods.args(x))
     end AppliedType

diff --git a/library/src/scala/quoted/Quotes.scala b/library/src/scala/quoted/Quotes.scala
@@ -2812,6 +2812,9 @@ trait Quotes { self: runtime.QuoteUnpickler & runtime.QuoteMatching =>
 
     /** Methods of the module object `val AppliedType` */
     trait AppliedTypeModule { this: AppliedType.type =>
+      /** Applied the type constructor `T` to a list of type arguments `T_1,..,T_n` to create `T[T_1,..,T_n]` */
+      @experimental
+      def apply(tycon: TypeRepr, args: List[TypeRepr]): AppliedType
       def unapply(x: AppliedType): (TypeRepr, List[TypeRepr])
     }
 

diff --git a/project/MiMaFilters.scala b/project/MiMaFilters.scala
@@ -4,12 +4,15 @@ import com.typesafe.tools.mima.core._
 object MiMaFilters {
   val Library: Seq[ProblemFilter] = Seq(
 
-    // Those are OK because user code is not allowed to inherit from Quotes:
+    // Experimental APIs that can be added in 3.2.0
+    ProblemFilters.exclude[ReversedMissingMethodProblem]("scala.quoted.Quotes#reflectModule#AppliedTypeModule.apply"),
     ProblemFilters.exclude[ReversedMissingMethodProblem]("scala.quoted.Quotes#reflectModule#SymbolMethods.asQuotes"),
-    ProblemFilters.exclude[ReversedMissingMethodProblem]("scala.quoted.Quotes#reflectModule#ClassDefModule.apply"),
-    ProblemFilters.exclude[ReversedMissingMethodProblem]("scala.quoted.Quotes#reflectModule#SymbolModule.newClass"),
     ProblemFilters.exclude[ReversedMissingMethodProblem]("scala.quoted.Quotes#reflectModule#SymbolMethods.typeRef"),
     ProblemFilters.exclude[ReversedMissingMethodProblem]("scala.quoted.Quotes#reflectModule#SymbolMethods.termRef"),
     ProblemFilters.exclude[ReversedMissingMethodProblem]("scala.quoted.Quotes#reflectModule#TypeTreeModule.ref"),
+
+    // Experimental APIs that still need some time before stabilization
+    ProblemFilters.exclude[ReversedMissingMethodProblem]("scala.quoted.Quotes#reflectModule#ClassDefModule.apply"),
+    ProblemFilters.exclude[ReversedMissingMethodProblem]("scala.quoted.Quotes#reflectModule#SymbolModule.newClass"),
   )
 }
diff --git a/tests/pos-macros/i14740/Macro_1.scala b/tests/pos-macros/i14740/Macro_1.scala
@@ -0,0 +1,11 @@
+import scala.quoted.*
+
+type Foo[T]
+
+transparent inline def emptyList[T]: Any = ${ impl[T] }
+
+private def impl[T: Type](using Quotes): Expr[Any] = {
+  import quotes.reflect._
+  val tpe = AppliedType(TypeRepr.of[Foo], List(TypeRepr.of[T])) // test AppliedType constructor
+  Typed('{???}.asTerm, Inferred(tpe)).asExpr // '{ ??? : Foo[T] }
+}
diff --git a/tests/pos-macros/i14740/Test_2.scala b/tests/pos-macros/i14740/Test_2.scala
@@ -0,0 +1,3 @@
+def test1: Foo[Any] = emptyList[Any]
+def test2: Foo[Int] = emptyList[Int]
+def test3: Foo[String] = emptyList[String]