[Compiler plugin] Add empty test for debugging purposes

Author: koperagen

plugins/kotlin-dataframe/testData/box/playground.kt

@@ -0,0 +1,9 @@
+import org.jetbrains.kotlinx.dataframe.*
+import org.jetbrains.kotlinx.dataframe.annotations.*
+import org.jetbrains.kotlinx.dataframe.api.*
+import org.jetbrains.kotlinx.dataframe.io.*
+
+fun box(): String {
+
+    return "OK"
+}

plugins/kotlin-dataframe/tests-gen/org/jetbrains/kotlin/fir/dataframe/DataFrameBlackBoxCodegenTestGenerated.java

@@ -304,6 +304,12 @@ public void testPlatformType() {
     runTest("testData/box/platformType.kt");
   }
 
+  @Test
+  @TestMetadata("playground.kt")
+  public void testPlayground() {
+    runTest("testData/box/playground.kt");
+  }
+
   @Test
   @TestMetadata("propertiesOrder.kt")
   public void testPropertiesOrder() {