bugfix: Only detect 100% sure test names

Previously, we would treat any string literal inside the apply of a test function as a name of such function, but each test name can actually be any kind of expression, so we would not detect the correc tname always.

Now, we only detect names of tests if they are of an expected format, either simple string, select or a tag.

Fixes #6617

metals/src/main/scala/scala/meta/internal/metals/testProvider/frameworks/MunitTestFinder.scala

@@ -189,24 +189,22 @@ class MunitTestFinder(
       tree: Tree
   ): Option[(Term.Name, Lit.String)] = {
 
-    @tailrec
-    def extractLiteralName(acc: List[Tree]): Option[Lit.String] = acc match {
-      case head :: tail =>
-        head match {
-          case lit: Lit.String => Some(lit)
-          case _ => extractLiteralName(head.children ::: tail)
-        }
-      case immutable.Nil => None
+    def extractLiteralName(tree: Tree): Option[Lit.String] = tree match {
+      case lit: Lit.String => Some(lit)
+      case Term.Select(lit: Lit.String, _) => Some(lit)
+      case Term.Apply(Term.Select(lit: Lit.String, Term.Name("tag")), _) =>
+        Some(lit)
+      case _ => None
     }
 
     @tailrec
     // find proper Apply in possibly multiple nested Applies
     def loop(acc: List[Tree]): Option[(Term.Name, Lit.String)] = acc match {
       case head :: tail =>
         head match {
-          case Term.Apply(term @ Term.Name(name), args)
+          case Term.Apply(term @ Term.Name(name), List(arg))
               if (testFunctionsNames(name)) =>
-            extractLiteralName(args) match {
+            extractLiteralName(arg) match {
               case Some(lit) =>
                 Some((term, lit))
               case None => loop(tail)

tests/unit/src/test/scala/tests/testProvider/TestSuitesProviderSuite.scala

@@ -285,6 +285,7 @@ class TestSuitesProviderSuite extends BaseLspSuite("testSuitesFinderSuite") {
         |      println(name)
         |      assertEquals(n1, n2)
         |    }
+        |  test("test1" + "test2") {}
         |}
         |""".stripMargin,
     List("app/src/main/scala/a/b/c/MunitTestSuite.scala"),