add compat

Author: kasiaMarek

metals/src/main/scala/scala/meta/internal/metals/Compilers.scala

@@ -606,7 +606,8 @@ class Compilers(
                 else InlayHintKind.Parameter
               hint.setKind(kind)
               hint.setData(
-                internal.pc.InlayHints.toData(params.uri(), List(Left("")))
+                internal.pc.InlayHints
+                  .toData(params.uri().toString(), List(Left("")))
               )
               hint
             }
@@ -624,7 +625,10 @@ class Compilers(
           }
           .map { hint =>
             hint.setPosition(adjust.adjustPos(hint.getPosition()))
-            hint
+            InlayHintCompat.maybeFixInlayHintData(
+              hint,
+              params.getTextDocument().getUri(),
+            )
           }
           .asJava
       }

metals/src/main/scala/scala/meta/internal/metals/InlayHintResolveProvider.scala

@@ -110,3 +110,27 @@ final class InlayHintResolveProvider(
   }
 
 }
+
+object InlayHintCompat {
+  private def parseData(
+      data: Array[Any]
+  ): List[Either[String, l.Position]] =
+    data.map {
+      case data: l.Position => Right(data)
+      case data: String => Left(data)
+    }.toList
+
+  // for compatibility with old inlay hint data
+  def maybeFixInlayHintData(hint: InlayHint, uri: String): InlayHint = {
+    if (hint.getData.isInstanceOf[Array[_]]) {
+      try {
+        val labelParts = parseData(hint.getData.asInstanceOf[Array[Any]])
+        hint.setData(InlayHints.toData(uri, labelParts))
+      } catch {
+        case e: Throwable =>
+          scribe.warn(s"Failed to fix inlay hint data: $e")
+      }
+    }
+    hint
+  }
+}

mtags-shared/src/main/scala/scala/meta/internal/pc/InlayHints.scala

@@ -41,7 +41,7 @@ case class InlayHints(
     hint.setPosition(pos)
     val (label, dataInfo) = labelParts.map(lp => (lp.label, lp.data)).unzip
     hint.setLabel(label.asJava)
-    hint.setData(InlayHints.toData(uri, dataInfo))
+    hint.setData(InlayHints.toData(uri.toString(), dataInfo))
     hint.setKind(kind)
     hint
   }
@@ -96,22 +96,24 @@ object InlayHints {
     buffer.toList.filter(_.name.nonEmpty)
   }
 
-  def toData(uri: URI, data: List[Either[String, l.Position]]): JsonElement =
+  def toData(uri: String, data: List[Either[String, l.Position]]): JsonElement =
     gson.toJsonTree(
       InlineHintData(
         uri,
         data.map {
           case Left(str) => LabelPartData("string", str, null)
           case Right(pos) => LabelPartData("position", null, pos)
-        }.asJava
+        }.toArray
       )
     )
 
-  def fromData(json: JsonElement): (URI, List[Either[String, l.Position]]) = {
+  def fromData(
+      json: JsonElement
+  ): (String, List[Either[String, l.Position]]) = {
     val data = gson.fromJson(json, classOf[InlineHintData])
     (
       data.uri,
-      data.labelParts.asScala.toList.map { part =>
+      data.labelParts.toList.map { part =>
         part.dataType match {
           case "position" => Right(part.position)
           case "string" => Left(part.string)
@@ -122,8 +124,8 @@ object InlayHints {
 }
 
 final case class InlineHintData(
-    uri: URI,
-    labelParts: java.util.List[LabelPartData]
+    uri: String,
+    labelParts: Array[LabelPartData]
 )
 
 // "string" or "position"

tests/unit/src/main/scala/tests/BaseInlayHintsExpectSuite.scala

@@ -3,6 +3,7 @@ package tests
 import scala.meta.internal.metals.CompilerInlayHintsParams
 import scala.meta.internal.metals.CompilerRangeParams
 import scala.meta.internal.metals.EmptyCancelToken
+import scala.meta.internal.metals.InlayHintCompat
 import scala.meta.internal.metals.MetalsEnrichments._
 import scala.meta.pc.PresentationCompiler
 
@@ -35,7 +36,15 @@ abstract class BaseInlayHintsExpectSuite(
             true,
           )
           val inlayHints =
-            compiler.inlayHints(pcParams).get().asScala.toList
+            compiler
+              .inlayHints(pcParams)
+              .get()
+              .asScala
+              .toList
+              .map(
+                InlayHintCompat
+                  .maybeFixInlayHintData(_, file.file.toURI.toString())
+              )
           TestInlayHints.applyInlayHints(file.code, inlayHints)
         },
       )