From a438ca16e6a2839fd0078d288ebdd8d6a6065a10 Mon Sep 17 00:00:00 2001
From: Jakub Ciesluk <323892@uwr.edu.pl>
Date: Fri, 29 Dec 2023 10:35:58 +0100
Subject: [PATCH] improvement: Remove semantic tokens fallback

---
 .../internal/metals/SemanticTokensProvider.scala | 16 +---------------
 .../internal/pc/PcSemanticTokensProvider.scala   |  3 ++-
 .../internal/pc/PcSemanticTokensProvider.scala   |  2 +-
 .../main/scala/tests/BaseWorksheetLspSuite.scala |  2 +-
 .../semanticTokens3/example/NamedArguments.scala |  2 +-
 .../example/StructuralTypes.scala                |  2 +-
 .../scala/tests/SemanticTokensLspSuite.scala     |  6 +++---
 7 files changed, 10 insertions(+), 23 deletions(-)

diff --git a/metals/src/main/scala/scala/meta/internal/metals/SemanticTokensProvider.scala b/metals/src/main/scala/scala/meta/internal/metals/SemanticTokensProvider.scala
index f8d7d62fdff..12cef05c00d 100644
--- a/metals/src/main/scala/scala/meta/internal/metals/SemanticTokensProvider.scala
+++ b/metals/src/main/scala/scala/meta/internal/metals/SemanticTokensProvider.scala
@@ -263,21 +263,7 @@ object SemanticTokensProvider {
         case _ => 0
       }
 
-    if (tokenType != -1) (tokenType, tokenModifier)
-    else if (!tk.isWhiteSpaceOrComment) {
-      tokenFallback(tk)
-    } else (-1, 0)
-
-  }
-  def tokenFallback(tk: scala.meta.tokens.Token): (Integer, Integer) = {
-    tk.text.headOption match {
-      case Some(upper) if upper.isUpper =>
-        (getTypeId(SemanticTokenTypes.Class), 0)
-      case Some(lower) if lower.isLower =>
-        val readOnlyMod = 1 << getModifierId(SemanticTokenModifiers.Readonly)
-        (getTypeId(SemanticTokenTypes.Variable), readOnlyMod)
-      case _ => (-1, 0)
-    }
+    (tokenType, tokenModifier)
   }
 
   private val SoftKeywordsUnapply = new SoftKeywords(scala.meta.dialects.Scala3)
diff --git a/mtags/src/main/scala-2/scala/meta/internal/pc/PcSemanticTokensProvider.scala b/mtags/src/main/scala-2/scala/meta/internal/pc/PcSemanticTokensProvider.scala
index 75179a44975..b7cd7c1ef7d 100644
--- a/mtags/src/main/scala-2/scala/meta/internal/pc/PcSemanticTokensProvider.scala
+++ b/mtags/src/main/scala-2/scala/meta/internal/pc/PcSemanticTokensProvider.scala
@@ -53,7 +53,8 @@ final class PcSemanticTokensProvider(
     ): Option[Node] = {
       val sym = symbol.fold(tree.symbol)(identity)
       if (
-        !pos.isDefined || sym == null || sym == compiler.NoSymbol || sym.isConstructor
+        !pos.isDefined || sym == null ||
+        sym == compiler.NoSymbol || sym.isError || sym.isConstructor
       ) {
         None
       } else {
diff --git a/mtags/src/main/scala-3/scala/meta/internal/pc/PcSemanticTokensProvider.scala b/mtags/src/main/scala-3/scala/meta/internal/pc/PcSemanticTokensProvider.scala
index baeae4508a3..f9762a8a729 100644
--- a/mtags/src/main/scala-3/scala/meta/internal/pc/PcSemanticTokensProvider.scala
+++ b/mtags/src/main/scala-3/scala/meta/internal/pc/PcSemanticTokensProvider.scala
@@ -71,7 +71,7 @@ final class PcSemanticTokensProvider(
           case tree: Tree =>
             symbol.fold(tree.symbol)(identity)
           case EndMarker(sym) => sym
-      if !pos.exists || sym == null || sym == NoSymbol then None
+      if !pos.exists || sym == null || sym == NoSymbol || sym.isError then None
       else
         Some(
           makeNode(
diff --git a/tests/unit/src/main/scala/tests/BaseWorksheetLspSuite.scala b/tests/unit/src/main/scala/tests/BaseWorksheetLspSuite.scala
index fc9083a471a..2a0f676a6a0 100644
--- a/tests/unit/src/main/scala/tests/BaseWorksheetLspSuite.scala
+++ b/tests/unit/src/main/scala/tests/BaseWorksheetLspSuite.scala
@@ -964,7 +964,7 @@ abstract class BaseWorksheetLspSuite(
   test("semantic-highlighting2") {
     val expected =
       s"""|
-          |<<val>>/*keyword*/ <<hellos>>/*variable,definition,readonly*/ = <<List>>/*class*/(<<hi1>>/*variable,readonly*/, <<hi2>>/*variable,readonly*/)
+          |<<val>>/*keyword*/ <<hellos>>/*variable,definition,readonly*/ = <<List>>/*class*/(hi1, hi2)
           |""".stripMargin
 
     val fileContent =
diff --git a/tests/unit/src/test/resources/semanticTokens3/example/NamedArguments.scala b/tests/unit/src/test/resources/semanticTokens3/example/NamedArguments.scala
index 7bd3bd278bf..28103967b44 100644
--- a/tests/unit/src/test/resources/semanticTokens3/example/NamedArguments.scala
+++ b/tests/unit/src/test/resources/semanticTokens3/example/NamedArguments.scala
@@ -28,7 +28,7 @@
 
   <<// vararg>>/*comment*/
   <<List>>/*class*/(
-    <<elems>>/*variable,readonly*/ = <<2>>/*number*/
+    elems = <<2>>/*number*/
   )
 
 }
\ No newline at end of file
diff --git a/tests/unit/src/test/resources/semanticTokens3/example/StructuralTypes.scala b/tests/unit/src/test/resources/semanticTokens3/example/StructuralTypes.scala
index 42055e4f567..c3895840dfc 100644
--- a/tests/unit/src/test/resources/semanticTokens3/example/StructuralTypes.scala
+++ b/tests/unit/src/test/resources/semanticTokens3/example/StructuralTypes.scala
@@ -17,4 +17,4 @@
   } = <<new>>/*keyword*/:
     <<def>>/*keyword*/ <<scalameta>>/*method,definition*/ = <<"4.0">>/*string*/
   <<V>>/*variable,readonly*/.<<scalameta>>/*method*/
-<<end>>/*keyword*/ <<StructuralTypes>>/*class*/
\ No newline at end of file
+<<end>>/*keyword*/ StructuralTypes
\ No newline at end of file
diff --git a/tests/unit/src/test/scala/tests/SemanticTokensLspSuite.scala b/tests/unit/src/test/scala/tests/SemanticTokensLspSuite.scala
index e014e2bc9e6..79d12faae85 100644
--- a/tests/unit/src/test/scala/tests/SemanticTokensLspSuite.scala
+++ b/tests/unit/src/test/scala/tests/SemanticTokensLspSuite.scala
@@ -128,7 +128,7 @@ class SemanticTokensLspSuite extends BaseLspSuite("SemanticTokens") {
     """|<<object>>/*keyword*/ <<Main>>/*class*/ {
        |  <<val>>/*keyword*/ <<x>>/*variable,definition,readonly*/ = <<List>>/*class*/(<<1>>/*number*/,<<2>>/*number*/,<<3>>/*number*/)
        |  <<val>>/*keyword*/ <<y>>/*variable,definition,readonly*/ = <<a>>/*variable,readonly*/ <<match>>/*keyword*/ {
-       |    <<case>>/*keyword*/ <<List>>/*class*/(<<a>>/*variable,readonly*/,<<b>>/*variable,readonly*/,<<c>>/*variable,readonly*/) <<=>>>/*operator*/ <<a>>/*variable,readonly*/
+       |    <<case>>/*keyword*/ <<List>>/*class*/(a,b,c) <<=>>>/*operator*/ <<a>>/*variable,readonly*/
        |    <<case>>/*keyword*/ <<_>>/*variable,readonly*/ <<=>>>/*operator*/ <<0>>/*number*/
        |  }
        |  <<val>>/*keyword*/ <<z>>/*variable,definition,readonly*/ = <<Set>>/*class*/(<<1>>/*number*/,<<2>>/*number*/,<<3>>/*number*/)
@@ -171,7 +171,7 @@ class SemanticTokensLspSuite extends BaseLspSuite("SemanticTokens") {
     "self-type",
     """|<<package>>/*keyword*/ <<a>>/*namespace*/
        |
-       |<<object>>/*keyword*/ <<Abc>>/*class*/ { <<self>>/*variable,readonly*/: <<Any>>/*class*/ <<=>>>/*operator*/
+       |<<object>>/*keyword*/ <<Abc>>/*class*/ { self: Any <<=>>>/*operator*/
        |  <<val>>/*keyword*/ <<xyz>>/*variable,definition,readonly*/ = <<1>>/*number*/
        |}
        |""".stripMargin,
@@ -189,7 +189,7 @@ class SemanticTokensLspSuite extends BaseLspSuite("SemanticTokens") {
        |}
        |
        |<<trait>>/*keyword*/ <<Tweeter>>/*interface,abstract*/ {
-       |  <<self>>/*variable,readonly*/: <<User>>/*interface,abstract*/ <<=>>>/*operator*/  <<// reassign this>>/*comment*/
+       |  self: <<User>>/*interface,abstract*/ <<=>>>/*operator*/  <<// reassign this>>/*comment*/
        |  <<def>>/*keyword*/ <<tweet>>/*method,definition*/(<<tweetText>>/*parameter,declaration,readonly*/: <<String>>/*type*/) = <<println>>/*method*/(<<s>>/*keyword*/<<">>/*string*/<<$>>/*keyword*/<<username>>/*method,abstract*/<<: >>/*string*/<<$>>/*keyword*/<<tweetText>>/*parameter,readonly*/<<">>/*string*/)
        |}
        |""".stripMargin,