Add accessiblity test

Author: Jentsch

compiler/src/dotty/tools/dotc/typer/Applications.scala

@@ -1259,7 +1259,7 @@ trait Applications extends Compatibility {
      *  whereas overloaded variants need to have a conforming variant.
      */
     def trySelectUnapply(qual: untpd.Tree)(fallBack: (Tree, TyperState) => Tree): Tree = {
-      // try first for non-overloaded, then for overloaded ocurrences
+      // try first for non-overloaded, then for overloaded occurrences
       def tryWithName(name: TermName)(fallBack: (Tree, TyperState) => Tree)(using Context): Tree = {
         def tryWithProto(pt: Type)(using Context) = {
           val result = typedExpr(untpd.Select(qual, name), new UnapplyFunProto(pt, this))
@@ -1394,6 +1394,7 @@ trait Applications extends Compatibility {
             resTypeOfUnapplyFn.member(nme.get).info
                 .orElse(resTypeOfUnapplyFn)
                 .member(tpnme.Names)
+                .accessibleFrom(selType)
                 // TODO: Is it possible to get something else than a SingleDenotation?
                 .asSingleDenotation
 
@@ -2141,7 +2142,7 @@ trait Applications extends Compatibility {
         mappedSym.rawParamss = alt.symbol.rawParamss
           // we need rawParamss to find parameters with default arguments,
           // but we do not need to be precise right now, since this is just a pre-test before
-          // we look up defult getters. If at some point we extract default arguments from the
+          // we look up default getters. If at some point we extract default arguments from the
           // parameter symbols themselves, we have to find the right parameter by name, not position.
           // That means it's OK to copy parameters wholesale rather than tailoring them to always
           // correspond to the type transformation.

tests/neg/negNamedPatternMatching.check

@@ -1,24 +1,28 @@
--- Error: tests/neg/negNamedPatternMatching.scala:18:20 ----------------------------------------------------------------
-18 |  case User(names = "Tom", city = city) => ??? // error
+-- Error: tests/neg/negNamedPatternMatching.scala:43:20 ----------------------------------------------------------------
+43 |  case User(names = "Tom", city = city) => null // error
    |                    ^^^^^
    |                    'names' is unknown
--- Error: tests/neg/negNamedPatternMatching.scala:19:22 ----------------------------------------------------------------
-19 |  case User(city = _, 10) => null // error
+-- Error: tests/neg/negNamedPatternMatching.scala:44:22 ----------------------------------------------------------------
+44 |  case User(city = _, 10) => null // error
    |                      ^^
    |                      Only named arguments allowed here
--- Error: tests/neg/negNamedPatternMatching.scala:20:18 ----------------------------------------------------------------
-20 |  case User(age = Age(years = 10)) => null // error
+-- Error: tests/neg/negNamedPatternMatching.scala:45:18 ----------------------------------------------------------------
+45 |  case User(age = Age(years = 10)) => null // error
    |                  ^^^
    |                  'patterns.Age' doesn't support named patterns
--- Error: tests/neg/negNamedPatternMatching.scala:23:11 ----------------------------------------------------------------
-23 |    name = "Tom 2",  // error
+-- Error: tests/neg/negNamedPatternMatching.scala:48:11 ----------------------------------------------------------------
+48 |    name = "Tom 2",  // error
    |           ^^^^^^^
    |           'name' was already used before
--- Error: tests/neg/negNamedPatternMatching.scala:24:11 ----------------------------------------------------------------
-24 |    name = "Tom 3" // error
+-- Error: tests/neg/negNamedPatternMatching.scala:49:11 ----------------------------------------------------------------
+49 |    name = "Tom 3" // error
    |           ^^^^^^^
    |           'name' was already used before
--- Error: tests/neg/negNamedPatternMatching.scala:26:22 ----------------------------------------------------------------
-26 |  case User(_, name = "Anna") => null // error
+-- Error: tests/neg/negNamedPatternMatching.scala:51:22 ----------------------------------------------------------------
+51 |  case User(_, name = "Anna") => null // error
    |                      ^^^^^^
    |                      name was already used as a positional pattern
+-- Error: tests/neg/negNamedPatternMatching.scala:52:19 ----------------------------------------------------------------
+52 |  case User(city = City(name = "Berlin")) => null // error
+   |                   ^^^^
+   |                   'patterns.City' doesn't support named patterns

tests/neg/negNamedPatternMatching.scala

@@ -10,17 +10,43 @@ object Age:
   def unapply(age: Age): Some[Int] =
     Some(age)
 
-case class User(name: String, age: Age, city: String)
+type City = City.City
 
-val user = User(name = "Anna", age = Age(10), city = "Berlin")
+object City:
+  opaque type City = String
+
+  class ExCity(city: City) extends Product:
+    def _1: String = city
+
+    private[City] type Names = "name" *: EmptyTuple
+
+    // Members declared in scala.Equals
+    def canEqual(that: Any): Boolean = ???
+
+    // Members declared in scala.Product
+    def productArity: Int = ???
+    def productElement(n: Int): Any = ???
+
+  City("test") match
+    case City("test") => null
+    case _ => null
+
+  def apply(name: String): City = name
+
+  def unapply(age: City): ExCity = ExCity(age)
+
+case class User(name: String, age: Age, city: City)
+
+val user = User(name = "Anna", age = Age(10), city = City("Berlin"))
 
 val annasCity = user match
-  case User(names = "Tom", city = city) => ??? // error
+  case User(names = "Tom", city = city) => null // error
   case User(city = _, 10) => null // error
   case User(age = Age(years = 10)) => null // error
   case User(
     name = "Tom",
     name = "Tom 2",  // error
     name = "Tom 3" // error
     ) => null
-  case User(_, name = "Anna") => null // error
+  case User(_, name = "Anna") => null // error
+  case User(city = City(name = "Berlin")) => null // error