services - migrate to junit 5 (#5613)

* services to junit5

* removed some junit4 engine imports

* updated some plugins test since these extend from testutil KV storage

* one more form of EPL v2

Signed-off-by: Sally MacFarlane <macfarla.github@gmail.com>

---------

Signed-off-by: Sally MacFarlane <macfarla.github@gmail.com>

enclave/build.gradle

@@ -17,8 +17,6 @@ dependencies {
   testImplementation 'org.assertj:assertj-core'
   testImplementation 'org.junit.jupiter:junit-jupiter'
 
-  testRuntimeOnly 'org.junit.vintage:junit-vintage-engine'
-
   // integration test dependencies.
   integrationTestImplementation project(':testutil')
   integrationTestImplementation 'org.assertj:assertj-core'
@@ -27,6 +25,4 @@ dependencies {
   integrationTestImplementation 'org.junit.jupiter:junit-jupiter-api'
   integrationTestImplementation 'org.mockito:mockito-core'
   integrationTestImplementation 'org.testcontainers:testcontainers'
-
-  integrationTestRuntimeOnly 'org.junit.jupiter:junit-jupiter'
 }

gradle/check-licenses.gradle

@@ -126,7 +126,8 @@ downloadLicenses {
     ],
     (epl2) : [
       'Eclipse Public License - v 2.0',
-      'Eclipse Public License version 2.0'
+      'Eclipse Public License version 2.0',
+      'Eclipse Public License v2.0'
     ],
     (mit) : [
       'MIT',

metrics/core/build.gradle

@@ -70,8 +70,6 @@ dependencies {
   testImplementation 'org.mockito:mockito-core'
   testImplementation 'org.mockito:mockito-junit-jupiter'
 
-  testRuntimeOnly 'org.junit.vintage:junit-vintage-engine'
-
   testSupportImplementation 'org.mockito:mockito-core'
 
   annotationProcessor 'com.google.dagger:dagger-compiler'

plugins/rocksdb/build.gradle

@@ -55,6 +55,7 @@ dependencies {
   testImplementation 'org.assertj:assertj-core'
   testImplementation 'org.junit.jupiter:junit-jupiter'
   testImplementation 'org.mockito:mockito-core'
+  testImplementation 'org.mockito:mockito-junit-jupiter'
 
   testRuntimeOnly 'org.junit.vintage:junit-vintage-engine'
 }

plugins/rocksdb/src/test/java/org/hyperledger/besu/plugin/services/storage/rocksdb/segmented/OptimisticTransactionDBRocksDBColumnarKeyValueStorageTest.java

@@ -25,6 +25,8 @@ import java.nio.file.Path;
 import java.util.Arrays;
 import java.util.List;
 
+import org.apache.tuweni.bytes.Bytes;
+
 public class OptimisticTransactionDBRocksDBColumnarKeyValueStorageTest
     extends RocksDBColumnarKeyValueStorageTest {
 
@@ -32,7 +34,9 @@ public class OptimisticTransactionDBRocksDBColumnarKeyValueStorageTest
   protected SegmentedKeyValueStorage<RocksDbSegmentIdentifier> createSegmentedStore()
       throws Exception {
     return new OptimisticRocksDBColumnarKeyValueStorage(
-        new RocksDBConfigurationBuilder().databaseDir(folder.newFolder().toPath()).build(),
+        new RocksDBConfigurationBuilder()
+            .databaseDir(folder.resolve(Bytes.random(9).toString()))
+            .build(),
         Arrays.asList(TestSegment.FOO, TestSegment.BAR),
         List.of(),
         new NoOpMetricsSystem(),

plugins/rocksdb/src/test/java/org/hyperledger/besu/plugin/services/storage/rocksdb/segmented/RocksDBColumnarKeyValueStorageTest.java

@@ -35,13 +35,12 @@ import java.util.Set;
 import java.util.function.Consumer;
 
 import org.apache.commons.lang3.tuple.Pair;
-import org.junit.Rule;
+import org.junit.jupiter.api.Test;
-import org.junit.Test;
+import org.junit.jupiter.api.io.TempDir;
-import org.junit.rules.TemporaryFolder;
 
 public abstract class RocksDBColumnarKeyValueStorageTest extends AbstractKeyValueStorageTest {
 
-  @Rule public final TemporaryFolder folder = new TemporaryFolder();
+  @TempDir public Path folder;
 
   @Test
   public void assertClear() throws Exception {
@@ -178,8 +177,8 @@ public abstract class RocksDBColumnarKeyValueStorageTest extends AbstractKeyValu
   }
 
   @Test
-  public void dbShouldIgnoreExperimentalSegmentsIfNotExisted() throws Exception {
+  public void dbShouldIgnoreExperimentalSegmentsIfNotExisted(@TempDir final Path testPath)
-    final Path testPath = folder.newFolder().toPath();
+      throws Exception {
     // Create new db should ignore experimental column family
     SegmentedKeyValueStorage<RocksDbSegmentIdentifier> store =
         createSegmentedStore(
@@ -195,8 +194,8 @@ public abstract class RocksDBColumnarKeyValueStorageTest extends AbstractKeyValu
   }
 
   @Test
-  public void dbShouldNotIgnoreExperimentalSegmentsIfExisted() throws Exception {
+  public void dbShouldNotIgnoreExperimentalSegmentsIfExisted(@TempDir final Path testPath)
-    final Path testPath = folder.newFolder().toPath();
+      throws Exception {
     // Create new db with experimental column family
     SegmentedKeyValueStorage<RocksDbSegmentIdentifier> store =
         createSegmentedStore(
@@ -225,8 +224,8 @@ public abstract class RocksDBColumnarKeyValueStorageTest extends AbstractKeyValu
   }
 
   @Test
-  public void dbWillBeBackwardIncompatibleAfterExperimentalSegmentsAreAdded() throws Exception {
+  public void dbWillBeBackwardIncompatibleAfterExperimentalSegmentsAreAdded(
-    final Path testPath = folder.newFolder().toPath();
+      @TempDir final Path testPath) throws Exception {
     // Create new db should ignore experimental column family
     SegmentedKeyValueStorage<RocksDbSegmentIdentifier> store =
         createSegmentedStore(

plugins/rocksdb/src/test/java/org/hyperledger/besu/plugin/services/storage/rocksdb/segmented/RocksDBKeyValueStorageTest.java

@@ -35,24 +35,24 @@ import org.hyperledger.besu.plugin.services.storage.rocksdb.configuration.RocksD
 import org.hyperledger.besu.plugin.services.storage.rocksdb.configuration.RocksDBConfigurationBuilder;
 import org.hyperledger.besu.plugin.services.storage.rocksdb.unsegmented.RocksDBKeyValueStorage;
 
+import java.nio.file.Path;
 import java.util.function.LongSupplier;
 
-import org.junit.Rule;
+import org.junit.jupiter.api.Test;
-import org.junit.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
-import org.junit.rules.TemporaryFolder;
+import org.junit.jupiter.api.io.TempDir;
-import org.junit.runner.RunWith;
 import org.mockito.ArgumentCaptor;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class RocksDBKeyValueStorageTest extends AbstractKeyValueStorageTest {
 
   @Mock private ObservableMetricsSystem metricsSystemMock;
   @Mock private LabelledMetric<OperationTimer> labelledMetricOperationTimerMock;
   @Mock private LabelledMetric<Counter> labelledMetricCounterMock;
   @Mock private OperationTimer operationTimerMock;
-  @Rule public final TemporaryFolder folder = new TemporaryFolder();
+  @TempDir static Path folder;
 
   @Override
   protected KeyValueStorage createStore() throws Exception {
@@ -131,6 +131,6 @@ public class RocksDBKeyValueStorageTest extends AbstractKeyValueStorageTest {
   }
 
   private RocksDBConfiguration config() throws Exception {
-    return new RocksDBConfigurationBuilder().databaseDir(folder.newFolder().toPath()).build();
+    return new RocksDBConfigurationBuilder().databaseDir(getTempSubFolder(folder)).build();
   }
 }

plugins/rocksdb/src/test/java/org/hyperledger/besu/plugin/services/storage/rocksdb/segmented/TransactionDBRocksDBColumnarKeyValueStorageTest.java

@@ -32,7 +32,7 @@ public class TransactionDBRocksDBColumnarKeyValueStorageTest
   protected SegmentedKeyValueStorage<RocksDbSegmentIdentifier> createSegmentedStore()
       throws Exception {
     return new TransactionDBRocksDBColumnarKeyValueStorage(
-        new RocksDBConfigurationBuilder().databaseDir(folder.newFolder().toPath()).build(),
+        new RocksDBConfigurationBuilder().databaseDir(getTempSubFolder(folder)).build(),
         Arrays.asList(TestSegment.FOO, TestSegment.BAR),
         List.of(),
         new NoOpMetricsSystem(),

services/kvstore/build.gradle

@@ -33,8 +33,6 @@ dependencies {
   implementation 'com.google.guava:guava'
 
   testImplementation project(':testutil')
-  testImplementation 'junit:junit'
+  testImplementation 'org.junit.jupiter:junit-jupiter'
   testImplementation 'org.assertj:assertj-core'
-
-  testRuntimeOnly 'org.junit.vintage:junit-vintage-engine'
 }

services/kvstore/src/test/java/org/hyperledger/besu/services/kvstore/LimitedInMemoryKeyValueStorageTest.java

@@ -20,7 +20,7 @@ import org.hyperledger.besu.kvstore.AbstractKeyValueStorageTest;
 import org.hyperledger.besu.plugin.services.storage.KeyValueStorage;
 import org.hyperledger.besu.plugin.services.storage.KeyValueStorageTransaction;
 
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 
 public class LimitedInMemoryKeyValueStorageTest extends AbstractKeyValueStorageTest {
 

services/pipeline/build.gradle

@@ -37,11 +37,9 @@ dependencies {
   implementation 'io.opentelemetry:opentelemetry-api'
   implementation 'com.google.guava:guava'
 
-  testImplementation 'junit:junit'
   testImplementation 'org.assertj:assertj-core'
   testImplementation 'org.awaitility:awaitility'
   testImplementation 'org.junit.jupiter:junit-jupiter'
   testImplementation 'org.mockito:mockito-core'
-
+  testImplementation 'org.mockito:mockito-junit-jupiter'
-  testRuntimeOnly 'org.junit.vintage:junit-vintage-engine'
 }

services/pipeline/src/test/java/org/hyperledger/besu/services/pipeline/AsyncOperationProcessorTest.java

@@ -26,7 +26,7 @@ import static org.mockito.Mockito.when;
 import java.util.concurrent.CompletableFuture;
 import java.util.function.Function;
 
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 
 public class AsyncOperationProcessorTest {
 

services/pipeline/src/test/java/org/hyperledger/besu/services/pipeline/BatchingReadPipeTest.java

@@ -27,7 +27,7 @@ import org.hyperledger.besu.plugin.services.metrics.Counter;
 import java.util.ArrayList;
 import java.util.List;
 
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 
 public class BatchingReadPipeTest {
 

services/pipeline/src/test/java/org/hyperledger/besu/services/pipeline/CompleterStageTest.java

@@ -20,7 +20,7 @@ import static org.hyperledger.besu.metrics.noop.NoOpMetricsSystem.NO_OP_COUNTER;
 import java.util.ArrayList;
 import java.util.List;
 
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 
 public class CompleterStageTest {
 

services/pipeline/src/test/java/org/hyperledger/besu/services/pipeline/FlatMapProcessorTest.java

@@ -24,7 +24,7 @@ import static org.mockito.Mockito.when;
 import java.util.function.Function;
 import java.util.stream.Stream;
 
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 
 public class FlatMapProcessorTest {
 

services/pipeline/src/test/java/org/hyperledger/besu/services/pipeline/IteratorSourceStageTest.java

@@ -18,7 +18,7 @@ import static org.assertj.core.api.Assertions.assertThat;
 import static org.hyperledger.besu.metrics.noop.NoOpMetricsSystem.NO_OP_COUNTER;
 
 import com.google.common.collect.Iterators;
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 
 public class IteratorSourceStageTest {
 

services/pipeline/src/test/java/org/hyperledger/besu/services/pipeline/MapProcessorTest.java

@@ -23,7 +23,7 @@ import static org.mockito.Mockito.when;
 
 import java.util.function.Function;
 
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 
 public class MapProcessorTest {
 

services/pipeline/src/test/java/org/hyperledger/besu/services/pipeline/PipeTest.java

@@ -24,7 +24,7 @@ import org.hyperledger.besu.plugin.services.metrics.Counter;
 import java.util.ArrayList;
 import java.util.List;
 
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 
 public class PipeTest {
   private final Counter inputCounter = mock(Counter.class);

services/pipeline/src/test/java/org/hyperledger/besu/services/pipeline/PipelineBuilderTest.java

@@ -51,8 +51,8 @@ import java.util.function.Function;
 import java.util.stream.Stream;
 
 import com.google.common.util.concurrent.ThreadFactoryBuilder;
-import org.junit.After;
+import org.junit.jupiter.api.AfterEach;
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 
 public class PipelineBuilderTest {
 
@@ -66,7 +66,7 @@ public class PipelineBuilderTest {
 
   private final ExecutorService executorService = Executors.newCachedThreadPool(THREAD_FACTORY);
 
-  @After
+  @AfterEach
   public void afterClass() throws Exception {
     executorService.shutdownNow();
     if (!executorService.awaitTermination(10, SECONDS)) {

services/pipeline/src/test/java/org/hyperledger/besu/services/pipeline/ProcessingStageTest.java

@@ -16,7 +16,7 @@ package org.hyperledger.besu.services.pipeline;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.hyperledger.besu.metrics.noop.NoOpMetricsSystem.NO_OP_COUNTER;
-import static org.mockito.Mockito.doAnswer;
+import static org.mockito.Mockito.lenient;
 import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.verifyNoMoreInteractions;
@@ -24,13 +24,13 @@ import static org.mockito.Mockito.when;
 
 import java.util.Locale;
 
-import org.junit.Before;
+import org.junit.jupiter.api.BeforeEach;
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class ProcessingStageTest {
 
   private final Pipe<String> inputPipe =
@@ -40,10 +40,11 @@ public class ProcessingStageTest {
   @Mock private Processor<String, String> singleStep;
   private ProcessingStage<String, String> stage;
 
-  @Before
+  @BeforeEach
   public void setUp() {
     stage = new ProcessingStage<>("name", inputPipe, outputPipe, singleStep);
-    doAnswer(
+    lenient()
+        .doAnswer(
             invocation -> {
               outputPipe.put(inputPipe.get().toLowerCase(Locale.UK));
               return 1;

services/pipeline/src/test/java/org/hyperledger/besu/services/pipeline/SharedWritePipeTest.java

@@ -18,7 +18,7 @@ import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.verifyNoInteractions;
 
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 
 public class SharedWritePipeTest {
 

services/tasks/build.gradle

@@ -40,9 +40,6 @@ dependencies {
   implementation 'io.vertx:vertx-core'
   implementation 'org.apache.tuweni:tuweni-bytes'
 
-  testImplementation 'junit:junit'
   testImplementation 'org.assertj:assertj-core'
   testImplementation 'org.junit.jupiter:junit-jupiter'
-
-  testRuntimeOnly 'org.junit.vintage:junit-vintage-engine'
 }

services/tasks/src/test/java/org/hyperledger/besu/services/tasks/AbstractTaskQueueTest.java

@@ -23,7 +23,7 @@ import java.util.concurrent.CountDownLatch;
 import java.util.function.Function;
 
 import org.apache.tuweni.bytes.Bytes;
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 
 abstract class AbstractTaskQueueTest<T extends TaskCollection<Bytes>> {
 

services/tasks/src/test/java/org/hyperledger/besu/services/tasks/CachingTaskCollectionTest.java

@@ -23,13 +23,13 @@ import java.util.List;
 import java.util.stream.Collectors;
 
 import org.apache.tuweni.bytes.Bytes;
-import org.junit.Before;
+import org.junit.jupiter.api.BeforeEach;
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 
 public class CachingTaskCollectionTest {
   private TaskCollection<Bytes> wrappedTaskCollection;
 
-  @Before
+  @BeforeEach
   public void setup() {
     wrappedTaskCollection = new InMemoryTaskQueue<>();
   }

services/tasks/src/test/java/org/hyperledger/besu/services/tasks/InMemoryTasksPriorityQueuesTest.java

@@ -21,7 +21,7 @@ import java.util.ArrayList;
 import java.util.List;
 import java.util.Objects;
 
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 
 public class InMemoryTasksPriorityQueuesTest {
 

testutil/build.gradle

@@ -36,7 +36,7 @@ dependencies {
   implementation 'com.google.guava:guava'
   implementation 'com.squareup.okhttp3:okhttp'
   implementation 'io.vertx:vertx-core'
-  implementation 'junit:junit'
+  implementation 'org.junit.jupiter:junit-jupiter'
   implementation 'org.apache.tuweni:tuweni-bytes'
   implementation 'org.apache.tuweni:tuweni-io'
   implementation 'org.apache.tuweni:tuweni-toml'

testutil/src/main/java/org/hyperledger/besu/kvstore/AbstractKeyValueStorageTest.java

@@ -21,6 +21,7 @@ import static org.assertj.core.api.Assertions.assertThat;
 import org.hyperledger.besu.plugin.services.storage.KeyValueStorage;
 import org.hyperledger.besu.plugin.services.storage.KeyValueStorageTransaction;
 
+import java.nio.file.Path;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
@@ -32,11 +33,12 @@ import java.util.stream.Stream;
 
 import org.apache.commons.lang3.tuple.Pair;
 import org.apache.tuweni.bytes.Bytes;
-import org.junit.Ignore;
+import org.assertj.core.api.Assertions;
-import org.junit.Test;
+import org.junit.jupiter.api.Disabled;
+import org.junit.jupiter.api.Test;
 
 /** The Abstract key value storage test. */
-@Ignore
+@Disabled
 public abstract class AbstractKeyValueStorageTest {
 
   /**
@@ -352,12 +354,16 @@ public abstract class AbstractKeyValueStorageTest {
    *
    * @throws Exception the exception
    */
-  @Test(expected = IllegalStateException.class)
+  @Test
   public void transactionPutAfterCommit() throws Exception {
+    Assertions.assertThatThrownBy(
+            () -> {
               final KeyValueStorage store = createStore();
               final KeyValueStorageTransaction tx = store.startTransaction();
               tx.commit();
               tx.put(bytesOf(1), bytesOf(1));
+            })
+        .isInstanceOf(IllegalStateException.class);
   }
 
   /**
@@ -365,12 +371,16 @@ public abstract class AbstractKeyValueStorageTest {
    *
    * @throws Exception the exception
    */
-  @Test(expected = IllegalStateException.class)
+  @Test
   public void transactionRemoveAfterCommit() throws Exception {
+    Assertions.assertThatThrownBy(
+            () -> {
               final KeyValueStorage store = createStore();
               final KeyValueStorageTransaction tx = store.startTransaction();
               tx.commit();
               tx.remove(bytesOf(1));
+            })
+        .isInstanceOf(IllegalStateException.class);
   }
 
   /**
@@ -378,12 +388,16 @@ public abstract class AbstractKeyValueStorageTest {
    *
    * @throws Exception the exception
    */
-  @Test(expected = IllegalStateException.class)
+  @Test
   public void transactionPutAfterRollback() throws Exception {
+    Assertions.assertThatThrownBy(
+            () -> {
               final KeyValueStorage store = createStore();
               final KeyValueStorageTransaction tx = store.startTransaction();
               tx.rollback();
               tx.put(bytesOf(1), bytesOf(1));
+            })
+        .isInstanceOf(IllegalStateException.class);
   }
 
   /**
@@ -391,12 +405,16 @@ public abstract class AbstractKeyValueStorageTest {
    *
    * @throws Exception the exception
    */
-  @Test(expected = IllegalStateException.class)
+  @Test
   public void transactionRemoveAfterRollback() throws Exception {
+    Assertions.assertThatThrownBy(
+            () -> {
               final KeyValueStorage store = createStore();
               final KeyValueStorageTransaction tx = store.startTransaction();
               tx.rollback();
               tx.remove(bytesOf(1));
+            })
+        .isInstanceOf(IllegalStateException.class);
   }
 
   /**
@@ -404,12 +422,16 @@ public abstract class AbstractKeyValueStorageTest {
    *
    * @throws Exception the exception
    */
-  @Test(expected = IllegalStateException.class)
+  @Test
   public void transactionCommitAfterRollback() throws Exception {
+    Assertions.assertThatThrownBy(
+            () -> {
               final KeyValueStorage store = createStore();
               final KeyValueStorageTransaction tx = store.startTransaction();
               tx.rollback();
               tx.commit();
+            })
+        .isInstanceOf(IllegalStateException.class);
   }
 
   /**
@@ -417,12 +439,16 @@ public abstract class AbstractKeyValueStorageTest {
    *
    * @throws Exception the exception
    */
-  @Test(expected = IllegalStateException.class)
+  @Test
   public void transactionCommitTwice() throws Exception {
+    Assertions.assertThatThrownBy(
+            () -> {
               final KeyValueStorage store = createStore();
               final KeyValueStorageTransaction tx = store.startTransaction();
               tx.commit();
               tx.commit();
+            })
+        .isInstanceOf(IllegalStateException.class);
   }
 
   /**
@@ -430,12 +456,16 @@ public abstract class AbstractKeyValueStorageTest {
    *
    * @throws Exception the exception
    */
-  @Test(expected = IllegalStateException.class)
+  @Test
   public void transactionRollbackAfterCommit() throws Exception {
+    Assertions.assertThatThrownBy(
+            () -> {
               final KeyValueStorage store = createStore();
               final KeyValueStorageTransaction tx = store.startTransaction();
               tx.commit();
               tx.rollback();
+            })
+        .isInstanceOf(IllegalStateException.class);
   }
 
   /**
@@ -443,12 +473,16 @@ public abstract class AbstractKeyValueStorageTest {
    *
    * @throws Exception the exception
    */
-  @Test(expected = IllegalStateException.class)
+  @Test
   public void transactionRollbackTwice() throws Exception {
+    Assertions.assertThatThrownBy(
+            () -> {
               final KeyValueStorage store = createStore();
               final KeyValueStorageTransaction tx = store.startTransaction();
               tx.rollback();
               tx.rollback();
+            })
+        .isInstanceOf(IllegalStateException.class);
   }
 
   /**
@@ -547,4 +581,15 @@ public abstract class AbstractKeyValueStorageTest {
   protected byte[] bytesOf(final int... bytes) {
     return Bytes.of(bytes).toArrayUnsafe();
   }
+
+  /**
+   * Create a sub folder from the given path, that will not conflict with other folders.
+   *
+   * @param folder the folder in which to create the sub folder
+   * @return the path representing the sub folder
+   * @throws Exception if the folder cannot be created
+   */
+  protected Path getTempSubFolder(final Path folder) throws Exception {
+    return java.nio.file.Files.createTempDirectory(folder, null);
+  }
 }