Set proper position for ValDefs generated from tuples

compiler/src/dotty/tools/dotc/ast/Desugar.scala

@@ -1143,10 +1143,11 @@ object desugar {
           ) // no `_`
 
       val ids = for ((named, _) <- vars) yield Ident(named.name)
-      val caseDef = CaseDef(pat, EmptyTree, makeTuple(ids))
       val matchExpr =
         if (tupleOptimizable) rhs
-        else Match(makeSelector(rhs, MatchCheck.IrrefutablePatDef), caseDef :: Nil)
+        else
+          val caseDef = CaseDef(pat, EmptyTree, makeTuple(ids)) 
+          Match(makeSelector(rhs, MatchCheck.IrrefutablePatDef), caseDef :: Nil)
       vars match {
         case Nil if !mods.is(Lazy) =>
           matchExpr
@@ -1166,8 +1167,16 @@ object desugar {
           val restDefs =
             for (((named, tpt), n) <- vars.zipWithIndex if named.name != nme.WILDCARD)
             yield
-              if (mods.is(Lazy)) derivedDefDef(original, named, tpt, selector(n), mods &~ Lazy)
-              else derivedValDef(original, named, tpt, selector(n), mods)
+              if mods.is(Lazy) then 
+                DefDef(named.name.asTermName, Nil, tpt, selector(n))
+                  .withMods(mods &~ Lazy)
+                  .withSpan(named.span)
+              else 
+                valDef(
+                  ValDef(named.name.asTermName, tpt, selector(n))
+                    .withMods(mods)
+                    .withSpan(named.span)
+                )
           flatTree(firstDef :: restDefs)
       }
   }

language-server/test/dotty/tools/languageserver/HoverTest.scala

@@ -234,7 +234,13 @@ class HoverTest {
 
   @Test def tuple: Unit = {
     code"""|object A:
-           |  val (${m1}first${m2}, second) = (1, 2)""".withSource
-      .hover(m1 to m2, hoverContent("Int"))
+           |  val (${m1}first${m2}, second) = (1.0, 2)""".withSource
+      .hover(m1 to m2, hoverContent("Double"))
+  }
+
+  @Test def multiAssigment: Unit = {
+    code"""|val ${m1}x${m2}, ${m3}y${m4} = 42.0""".withSource
+      .hover(m1 to m2, hoverContent("Double"))
+      .hover(m3 to m4, hoverContent("Double"))
   }
 }

language-server/test/dotty/tools/languageserver/WorksheetTest.scala

@@ -93,12 +93,6 @@ class WorksheetTest {
         ((m1 to m2), "val res0: String = odd"))
   }
 
-  @Test def patternMatching1: Unit = {
-    ws"""${m1}val (foo, bar) = (1, 2)${m2}""".withSource
-      .run(m1,
-        ((m1 to m2), s"val foo: Int = 1${nl}val bar: Int = 2"))
-  }
-
   @Test def evaluationException: Unit = {
     ws"""${m1}val foo = 1 / 0${m2}
          ${m3}val bar = 2${m4}""".withSource

tests/neg/t5702-neg-bad-and-wild.check

@@ -23,11 +23,17 @@
    |
    | longer explanation available when compiling with `-explain`
 -- [E032] Syntax Error: tests/neg/t5702-neg-bad-and-wild.scala:23:17 ---------------------------------------------------
-23 |    val K(ns @ _*, x) = k // error: pattern expected
+23 |    val K(ns @ _*, xx) = k // error: pattern expected
    |                 ^
    |                 pattern expected
    |
    | longer explanation available when compiling with `-explain`
+-- [E161] Naming Error: tests/neg/t5702-neg-bad-and-wild.scala:24:10 ---------------------------------------------------
+24 |    val K(x) = k // error: x is already defined as value x
+   |    ^^^^^^^^^^^^
+   |    x is already defined as value x
+   |
+   |    Note that overloaded methods must all be defined in the same group of toplevel definitions
 -- Error: tests/neg/t5702-neg-bad-and-wild.scala:10:21 -----------------------------------------------------------------
 10 |      case List(1, _*,) => // error: pattern expected // error
    |                     ^

tests/neg/t5702-neg-bad-and-wild.scala

@@ -20,7 +20,8 @@ object Test {
 // good syntax, bad semantics, detected by typer
 //gowild.scala:14: error: star patterns must correspond with varargs parameters
     val K(x @ _*) = k
-    val K(ns @ _*, x) = k // error: pattern expected
+    val K(ns @ _*, xx) = k // error: pattern expected
+    val K(x) = k // error: x is already defined as value x
     val (b, _ * ) = (5,6) // ok
 // no longer complains
 //bad-and-wild.scala:15: error: ')' expected but '}' found.