fix: [SemanticDB] Emit SymbolInformation and Occurrence for anonymous class

[tanishiking]

fix #15852

This commit enables ExtractSemanticDB to emit SymbolInformation and
SymbolOccurrence of anonymous classes.

e.g.

trait Foo:
  def foo: String

val foo1: Foo = new Foo { def foo: String = ??? }
val foo2: Foo = new { def foo: String = ??? }

While Scala2 semanticdb-plugin emit symbols for the anonymous class.

Lack of the symbol information / occurrence led Metals not being able to
find those anonymous classes as implementations by go-to-implementation from trait Foo.
see: scalameta/metals#4246

Confirmed this change fix the metals's go-to-implementation issue

by the following diff

diff --git a/project/V.scala b/project/V.scala
index 19fabea1db..be984e0bdd 100644
--- a/project/V.scala
+++ b/project/V.scala
@@ -6,7 +6,7 @@ object V {
   val scala212 = "2.12.16"
   val scala213 = "2.13.8"
   val scala3 = "3.1.3"
-  val nextScala3RC = "3.2.0-RC3"
+  val nextScala3RC = "3.2.1-RC1-bin-SNAPSHOT"
   val sbtScala = "2.12.14"
   val ammonite212Version = "2.12.16"
   val ammonite213Version = "2.13.8"
diff --git a/tests/unit/src/main/scala/tests/BaseRangesSuite.scala b/tests/unit/src/main/scala/tests/BaseRangesSuite.scala
index 8304e59eab..7bef87163a 100644
--- a/tests/unit/src/main/scala/tests/BaseRangesSuite.scala
+++ b/tests/unit/src/main/scala/tests/BaseRangesSuite.scala
@@ -50,8 +50,7 @@ abstract class BaseRangesSuite(name: String) extends BaseLspSuite(name) {
           s"""/metals.json
              |{"a":
              |  {
-             |    "scalaVersion" : "$actualScalaVersion",
-             |    "libraryDependencies": ${toJsonArray(libraryDependencies)}
+             |    "scalaVersion" : "$actualScalaVersion"
              |  }
              |}
              |${input
diff --git a/tests/unit/src/test/scala/tests/ImplementationLspSuite.scala b/tests/unit/src/test/scala/tests/ImplementationLspSuite.scala
index 4bc5dd599a..2da9827c0a 100644
--- a/tests/unit/src/test/scala/tests/ImplementationLspSuite.scala
+++ b/tests/unit/src/test/scala/tests/ImplementationLspSuite.scala
@@ -493,9 +493,22 @@ class ImplementationLspSuite extends BaseRangesSuite("implementation") {
        |package a
        |trait A@@nimal
        |object Main{
-       |  val animal = new <<>>Animal{ def field(d : String) : Int = 123 }
+       |  val animal = <<>>new Animal{ def field(d : String) : Int = 123 }
        |}
        |""".stripMargin,
+    scalaVersion = Some("3.2.1-RC3-bin-SNAPSHOT"),
+  )
+
+  check(
+    "anon2",
+    """|/a/src/main/scala/a/Main.scala
+       |package a
+       |trait A@@nimal
+       |object Main{
+       |  val animal: Animal = <<>>new <<>>{ def field(d : String) : Int = 123 }
+       |}
+       |""".stripMargin,
+    scalaVersion = Some("3.2.1-RC3-bin-SNAPSHOT"),
   )
 
   check(

[tanishiking]

The change seems kind of monkey patch, maybe we should refactor ExtractSemanticDB at some point.

[bishabosha]

A redesign would be welcome - The only specification I used in the original implementation was comparing with the expect files from scalameta's semanticdb tests, so everything grew organically around that

[bishabosha]

did a rebase due to conflict