bugfix: Don't try to discover test frameworks if none exist

Previously, even if node_modules wouldn't exist we would run test discovery, which requires the node_modules and the scripts it contains. Now, we show an error in such a case. This seems to have hanged the node process causing no tests to be discovered.

I am not sure how to properly test it yet, but I need to dig into the JS part at some point since from earlier discussions with Sebastien the bridges might be problematic.

Author: tgodzik

bridges/scalajs-1/src/main/scala/bloop/scalajs/JsBridge.scala

@@ -147,25 +147,32 @@ object JsBridge {
       env: Map[String, String]
   ): (List[sbt.testing.Framework], () => Unit) = {
     implicit val debugFilter: DebugFilter = DebugFilter.Test
-    val nodeModules = baseDirectory.resolve("node_modules").toString
-    logger.debug("Node.js module path: " + nodeModules)
-    val fullEnv = Map("NODE_PATH" -> nodeModules) ++ env
-    val config =
-      NodeJSConfig().withExecutable(nodePath).withCwd(Some(baseDirectory)).withEnv(fullEnv)
-    val nodeEnv =
-      if (!jsConfig.jsdom.contains(true)) new NodeJSEnv(logger, config)
-      else new JsDomNodeJsEnv(logger, config)
-
-    // The order of the scripts mandates the load order in the JavaScript runtime
-    val input = jsConfig.kind match {
-      case ModuleKindJS.NoModule => Input.Script(jsPath)
-      case ModuleKindJS.CommonJSModule => Input.CommonJSModule(jsPath)
-      case ModuleKindJS.ESModule => Input.ESModule(jsPath)
-    }
+    val nodeModules = baseDirectory.resolve("node_modules")
+    if (nodeModules.toFile().exists()) {
+      logger.debug("Node.js module path: " + nodeModules.toString())
+      val fullEnv = Map("NODE_PATH" -> nodeModules.toString()) ++ env
+      val config =
+        NodeJSConfig().withExecutable(nodePath).withCwd(Some(baseDirectory)).withEnv(fullEnv)
+      val nodeEnv =
+        if (!jsConfig.jsdom.contains(true)) new NodeJSEnv(logger, config)
+        else new JsDomNodeJsEnv(logger, config)
+
+      // The order of the scripts mandates the load order in the JavaScript runtime
+      val input = jsConfig.kind match {
+        case ModuleKindJS.NoModule => Input.Script(jsPath)
+        case ModuleKindJS.CommonJSModule => Input.CommonJSModule(jsPath)
+        case ModuleKindJS.ESModule => Input.ESModule(jsPath)
+      }
 
-    val testConfig = TestAdapter.Config().withLogger(new Logger(logger))
-    val adapter = new TestAdapter(nodeEnv, Seq(input), testConfig)
-    val result = adapter.loadFrameworks(frameworkNames).flatMap(_.toList)
-    (result, () => adapter.close())
+      val testConfig = TestAdapter.Config().withLogger(new Logger(logger))
+      val adapter = new TestAdapter(nodeEnv, Seq(input), testConfig)
+      val result = adapter.loadFrameworks(frameworkNames).flatMap(_.toList)
+      (result, () => adapter.close())
+    } else {
+      logger.error(
+        s"Cannot discover test frameworks, missing node_modules in test project, expected them at $nodeModules"
+      )
+      (Nil, () => ())
+    }
   }
 }

bridges/scalajs-1/src/main/scala/bloop/scalajs/jsenv/NodeJsEnv.scala

@@ -124,6 +124,7 @@ final class NodeJSEnv(logger: Logger, config: NodeJSConfig) extends JSEnv {
   }
 
   private def internalStart(input: Seq[Input], runConfig: RunConfig): JSRun = {
+    runConfig.logger.debug("Using input file: " + (input.mkString(",")))
     NodeJSEnv.internalStart(logger, config, env)(NodeJSEnv.write(input), runConfig)
   }
 
@@ -290,7 +291,10 @@ object NodeJSEnv {
       import scala.concurrent.ExecutionContext.Implicits.global
 
       private val isClosed = AtomicBoolean(false)
-      override def future: Future[Unit] = cancellable.map(_ => ())
+      override def future: Future[Unit] = cancellable.map { results =>
+        logger.debug(s"Finished with results: ${results}")
+        ()
+      }
       override def close(): Unit = {
         // Make sure we only destroy the process once, the test adapter can call this several times!
         if (!isClosed.getAndSet(true)) {