[FLINK-4009][tests] fix Scala Shell external library tests for IntelliJ

flink-scala-shell/src/test/resources/log4j-test.properties

@@ -17,8 +17,7 @@
 ################################################################################
 
 
-# Convenience file for local debugging of the JobManager/TaskManager.
-log4j.rootLogger=OFF, console
+log4j.rootLogger=ERROR, console
 log4j.appender.console=org.apache.log4j.ConsoleAppender
 log4j.appender.console.layout=org.apache.log4j.PatternLayout
 log4j.appender.console.layout.ConversionPattern=%d{HH:mm:ss,SSS} %-5p %-60c %x - %m%n

flink-scala-shell/src/test/scala/org/apache/flink/api/scala/ScalaShellITCase.scala

@@ -173,7 +173,10 @@ class ScalaShellITCase extends TestLogger {
 
     // find jar file that contains the ml code
     var externalJar = ""
-    val folder = new File("../../flink-libraries/flink-ml/target/")
+    val folder = findLibraryFolder(
+      "../flink-libraries/flink-ml/target/",
+      "../../flink-libraries/flink-ml/target/")
+
     val listOfFiles = folder.listFiles()
 
     for (i <- listOfFiles.indices) {
@@ -208,7 +211,10 @@ class ScalaShellITCase extends TestLogger {
 
     // find jar file that contains the ml code
     var externalJar = ""
-    val folder = new File("../../flink-libraries/flink-ml/target/")
+    val folder = findLibraryFolder(
+      "../flink-libraries/flink-ml/target/",
+      "../../flink-libraries/flink-ml/target/")
+
     val listOfFiles = folder.listFiles()
 
     for (i <- listOfFiles.indices) {
@@ -406,4 +412,14 @@ object ScalaShellITCase {
 
     out.toString + stdout
   }
+
+  def findLibraryFolder(paths: String*): File = {
+    for (path <- paths) {
+      val folder = new File(path)
+      if (folder.exists()) {
+        return folder
+      }
+    }
+    throw new RuntimeException("Library folder not found in any of the supplied paths!")
+  }
 }