From e81e5db1909d90af1501703e7b4d6f760247c85e Mon Sep 17 00:00:00 2001
From: Tomasz Godzik <tgodzik@virtuslab.com>
Date: Fri, 26 Jul 2024 12:55:29 +0200
Subject: [PATCH] improvement: Timeout when resolving mtags for a long time

Otherwise this timeouts tests and can actually hang metals totally.
---
 .../meta/internal/metals/MtagsResolver.scala  | 29 ++++++++++++++-----
 .../metals/doctor/ProblemResolver.scala       |  3 +-
 .../main/scala/tests/TestMtagsResolver.scala  |  6 +++-
 3 files changed, 28 insertions(+), 10 deletions(-)

diff --git a/metals/src/main/scala/scala/meta/internal/metals/MtagsResolver.scala b/metals/src/main/scala/scala/meta/internal/metals/MtagsResolver.scala
index 2b81d72c9aa..7b0f607d572 100644
--- a/metals/src/main/scala/scala/meta/internal/metals/MtagsResolver.scala
+++ b/metals/src/main/scala/scala/meta/internal/metals/MtagsResolver.scala
@@ -2,6 +2,9 @@ package scala.meta.internal.metals
 
 import java.util.concurrent.ConcurrentHashMap
 
+import scala.concurrent.Await
+import scala.concurrent.ExecutionContext
+import scala.concurrent.Future
 import scala.concurrent.duration._
 import scala.util.control.NonFatal
 
@@ -14,14 +17,18 @@ trait MtagsResolver {
    * Try and resolve mtags module for a given version of Scala.
    * @return information to use and load the presentation compiler implementation
    */
-  def resolve(scalaVersion: String): Option[MtagsBinaries]
+  def resolve(scalaVersion: String)(implicit
+      ec: ExecutionContext
+  ): Option[MtagsBinaries]
 
   /**
    * Check if a given Scala version is supported in Metals.
    *
    * @param version Scala version to check
    */
-  def isSupportedScalaVersion(version: String): Boolean =
+  def isSupportedScalaVersion(version: String)(implicit
+      ec: ExecutionContext
+  ): Boolean =
     resolve(version).isDefined
 
   /**
@@ -102,7 +109,9 @@ object MtagsResolver {
     def isSupportedInOlderVersion(version: String): Boolean =
       removedScalaVersions.contains(version)
 
-    def resolve(scalaVersion: String): Option[MtagsBinaries] = {
+    def resolve(
+        scalaVersion: String
+    )(implicit ec: ExecutionContext): Option[MtagsBinaries] = {
       if (hasStablePresentationCompiler(scalaVersion))
         resolve(
           scalaVersion,
@@ -130,7 +139,7 @@ object MtagsResolver {
         scalaVersion: String,
         original: Option[String],
         resolveType: ResolveType.Value,
-    ): Option[MtagsBinaries] = {
+    )(implicit ec: ExecutionContext): Option[MtagsBinaries] = {
 
       def fetch(fetchResolveType: ResolveType.Value, tries: Int = 5): State =
         try {
@@ -143,12 +152,16 @@ object MtagsResolver {
               s"$scalaVersion is no longer supported in the current Metals versions, using the last known supported version $metalsVersion"
             )
           }
-          val jars = fetchResolveType match {
-            case ResolveType.StablePC =>
-              Embedded.downloadScala3PresentationCompiler(scalaVersion)
-            case _ => Embedded.downloadMtags(scalaVersion, metalsVersion)
+          val jarsFuture = Future {
+            fetchResolveType match {
+              case ResolveType.StablePC =>
+                Embedded.downloadScala3PresentationCompiler(scalaVersion)
+              case _ => Embedded.downloadMtags(scalaVersion, metalsVersion)
+            }
           }
 
+          val jars = Await.result(jarsFuture, 60.seconds)
+
           State.Success(
             MtagsBinaries.Artifacts(
               scalaVersion,
diff --git a/metals/src/main/scala/scala/meta/internal/metals/doctor/ProblemResolver.scala b/metals/src/main/scala/scala/meta/internal/metals/doctor/ProblemResolver.scala
index baf1dfb7d06..91252d82909 100644
--- a/metals/src/main/scala/scala/meta/internal/metals/doctor/ProblemResolver.scala
+++ b/metals/src/main/scala/scala/meta/internal/metals/doctor/ProblemResolver.scala
@@ -1,6 +1,7 @@
 package scala.meta.internal.metals.doctor
 
 import scala.collection.mutable.ListBuffer
+import scala.concurrent.ExecutionContext
 
 import scala.meta.internal.bsp.BspSession
 import scala.meta.internal.metals.BloopServers
@@ -23,7 +24,7 @@ class ProblemResolver(
     currentBuildServer: () => Option[BspSession],
     isTestExplorerProvider: () => Boolean,
     javaInfo: () => Option[JavaInfo],
-) {
+)(implicit ec: ExecutionContext) {
 
   def isUnsupportedBloopVersion(): Boolean = {
     currentBuildServer() match {
diff --git a/tests/unit/src/main/scala/tests/TestMtagsResolver.scala b/tests/unit/src/main/scala/tests/TestMtagsResolver.scala
index 760f2c95a7b..52062c96bf4 100644
--- a/tests/unit/src/main/scala/tests/TestMtagsResolver.scala
+++ b/tests/unit/src/main/scala/tests/TestMtagsResolver.scala
@@ -1,5 +1,7 @@
 package tests
 
+import scala.concurrent.ExecutionContext
+
 import scala.meta.internal.metals.MtagsBinaries
 import scala.meta.internal.metals.MtagsResolver
 import scala.meta.internal.metals.ScalaVersions
@@ -19,7 +21,9 @@ class TestMtagsResolver(checkCoursier: Boolean) extends MtagsResolver {
       Some(MtagsBinaries.BuildIn)
     else None
 
-  override def resolve(scalaVersion: String): Option[MtagsBinaries] = {
+  override def resolve(
+      scalaVersion: String
+  )(implicit ec: ExecutionContext): Option[MtagsBinaries] = {
     if (checkCoursier)
       default.resolve(scalaVersion).orElse(localCheck(scalaVersion))
     else localCheck(scalaVersion)