GCS NIO: fix one test to work with the other unit tests (#3454)

google-cloud-clients/google-cloud-contrib/google-cloud-nio/src/test/java/com/google/cloud/storage/contrib/nio/CloudStorageReadTest.java

@@ -91,6 +91,9 @@ public void testInputStreamReads() throws IOException, InterruptedException {
         // reading past the end
         int eof = is.read(buf, 0, 1);
         assertWithMessage("EOF should return -1").that(eof).isEqualTo(-1);
+      } finally {
+        // clean up
+        Files.delete(p);
       }
     }
   }
@@ -121,6 +124,9 @@ public void testChannelReads() throws IOException, InterruptedException {
         buf.clear();
         int eof = chan.read(buf);
         assertWithMessage("EOF should return -1").that(eof).isEqualTo(-1);
+      } finally {
+        // clean up
+        Files.delete(p);
       }
     }
   }

google-cloud-clients/google-cloud-contrib/google-cloud-nio/src/test/java/com/google/cloud/storage/contrib/nio/it/ITGcsNio.java

@@ -531,6 +531,10 @@ public void testListFiles() throws IOException {
         got.add(path);
       }
       assertThat(got).containsExactlyElementsIn(goodPaths);
+      // clean up
+      for (Path path : paths) {
+        Files.delete(path);
+      }
     }
   }
 
@@ -556,10 +560,12 @@ public void testDeleteRecursive() throws IOException {
 
   @Test
   public void testListFilesInRootDirectory() throws IOException {
+    // We must explicitly set the storageOptions, because the unit tests
+    // set the fake storage as default but we want to access the real storage.
     CloudStorageFileSystem fs = CloudStorageFileSystem.forBucket(
       BUCKET, CloudStorageConfiguration.builder().permitEmptyPathComponents(true)
-      .build());
-    
+      .build(), storageOptions);
+
     // test absolute path
     Path rootPath = fs.getPath("");
     List<String> objectNames = new ArrayList<String>();