fix: correctly auto import when there is a renamed symbol with the same name in scope

Author: kasiaMarek

presentation-compiler/src/main/dotty/tools/pc/IndexedContext.scala

@@ -36,8 +36,8 @@ sealed trait IndexedContext:
             Result.InScope
       // when all the conflicting symbols came from an old version of the file
       case Some(symbols) if symbols.nonEmpty && symbols.forall(_.isStale) => Result.Missing
-      case Some(_) => Result.Conflict
-      case None => Result.Missing
+      case Some(symbols) if symbols.exists(rename(_).isEmpty) => Result.Conflict
+      case _ => Result.Missing
   end lookupSym
 
   /**

presentation-compiler/test/dotty/tools/pc/tests/completion/CompletionSuite.scala

@@ -1952,3 +1952,34 @@ class CompletionSuite extends BaseCompletionSuite:
       """TestEnum test
         |""".stripMargin,
     )
+
+  @Test def `i6477-1` =
+    checkEdit(
+      """|package a
+         |import a.b.SomeClass as SC
+         |
+         |package b {
+         |  class SomeClass
+         |}
+         |package c {
+         |  class SomeClass
+         |}
+         |
+         |val bar: SC = ???
+         |val foo: SomeClass@@
+         |""".stripMargin,
+      """|package a
+         |import a.b.SomeClass as SC
+         |import a.c.SomeClass
+         |
+         |package b {
+         |  class SomeClass
+         |}
+         |package c {
+         |  class SomeClass
+         |}
+         |
+         |val bar: SC = ???
+         |val foo: SomeClass
+         |""".stripMargin,
+    )

presentation-compiler/test/dotty/tools/pc/tests/edit/AutoImportsSuite.scala

@@ -405,6 +405,37 @@ class AutoImportsSuite extends BaseAutoImportsSuite:
          |""".stripMargin,
     )
 
+  @Test def `i6477` =
+    checkEdit(
+      """|package a
+         |import a.b.SomeClass as SC
+         |
+         |package b {
+         |  class SomeClass
+         |}
+         |package c {
+         |  class SomeClass
+         |}
+         |
+         |val bar: SC = ???
+         |val foo: <<SomeClass>> = ???
+         |""".stripMargin,
+      """|package a
+         |import a.b.SomeClass as SC
+         |import a.c.SomeClass
+         |
+         |package b {
+         |  class SomeClass
+         |}
+         |package c {
+         |  class SomeClass
+         |}
+         |
+         |val bar: SC = ???
+         |val foo: SomeClass = ???
+         |""".stripMargin
+    )
+
   private def ammoniteWrapper(code: String): String =
     // Vaguely looks like a scala file that Ammonite generates
     // from a sc file.