Move TestUtil.createTempFolder and TestUtil.recursiveDelete to Util class

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=150190520

library/src/androidTest/java/com/google/android/exoplayer2/upstream/cache/CacheDataSourceTest.java

@@ -20,9 +20,9 @@ import android.test.InstrumentationTestCase;
 import android.test.MoreAsserts;
 import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.testutil.FakeDataSource;
-import com.google.android.exoplayer2.testutil.TestUtil;
 import com.google.android.exoplayer2.upstream.DataSpec;
 import com.google.android.exoplayer2.upstream.FileDataSource;
+import com.google.android.exoplayer2.util.Util;
 import java.io.File;
 import java.io.IOException;
 import java.util.Arrays;
@@ -42,13 +42,13 @@ public class CacheDataSourceTest extends InstrumentationTestCase {
 
   @Override
   protected void setUp() throws Exception {
-    cacheDir = TestUtil.createTempFolder(getInstrumentation().getContext());
+    cacheDir = Util.createTempDirectory(getInstrumentation().getContext(), "ExoPlayerTest");
     simpleCache = new SimpleCache(cacheDir, new NoOpCacheEvictor());
   }
 
   @Override
   protected void tearDown() throws Exception {
-    TestUtil.recursiveDelete(cacheDir);
+    Util.recursiveDelete(cacheDir);
   }
 
   public void testMaxCacheFileSize() throws Exception {

library/src/androidTest/java/com/google/android/exoplayer2/upstream/cache/CachedContentIndexTest.java

@@ -4,7 +4,7 @@ import android.test.InstrumentationTestCase;
 import android.test.MoreAsserts;
 import android.util.SparseArray;
 import com.google.android.exoplayer2.C;
-import com.google.android.exoplayer2.testutil.TestUtil;
+import com.google.android.exoplayer2.util.Util;
 import java.io.File;
 import java.io.FileInputStream;
 import java.io.FileOutputStream;
@@ -36,13 +36,13 @@ public class CachedContentIndexTest extends InstrumentationTestCase {
 
   @Override
   public void setUp() throws Exception {
-    cacheDir = TestUtil.createTempFolder(getInstrumentation().getContext());
+    cacheDir = Util.createTempDirectory(getInstrumentation().getContext(), "ExoPlayerTest");
     index = new CachedContentIndex(cacheDir);
   }
 
   @Override
   protected void tearDown() throws Exception {
-    TestUtil.recursiveDelete(cacheDir);
+    Util.recursiveDelete(cacheDir);
   }
 
   public void testAddGetRemove() throws Exception {

library/src/androidTest/java/com/google/android/exoplayer2/upstream/cache/CachedRegionTrackerTest.java

@@ -18,6 +18,7 @@ package com.google.android.exoplayer2.upstream.cache;
 import android.test.InstrumentationTestCase;
 import com.google.android.exoplayer2.extractor.ChunkIndex;
 import com.google.android.exoplayer2.testutil.TestUtil;
+import com.google.android.exoplayer2.util.Util;
 import java.io.File;
 import java.io.IOException;
 import org.mockito.Mock;
@@ -49,13 +50,13 @@ public final class CachedRegionTrackerTest extends InstrumentationTestCase {
 
     tracker = new CachedRegionTracker(cache, CACHE_KEY, CHUNK_INDEX);
 
-    cacheDir = TestUtil.createTempFolder(getInstrumentation().getContext());
+    cacheDir = Util.createTempDirectory(getInstrumentation().getContext(), "ExoPlayerTest");
     index = new CachedContentIndex(cacheDir);
   }
 
   @Override
   protected void tearDown() throws Exception {
-    TestUtil.recursiveDelete(cacheDir);
+    Util.recursiveDelete(cacheDir);
   }
 
   public void testGetRegion_noSpansInCache() {

library/src/androidTest/java/com/google/android/exoplayer2/upstream/cache/SimpleCacheSpanTest.java

@@ -16,7 +16,7 @@
 package com.google.android.exoplayer2.upstream.cache;
 
 import android.test.InstrumentationTestCase;
-import com.google.android.exoplayer2.testutil.TestUtil;
+import com.google.android.exoplayer2.util.Util;
 import java.io.File;
 import java.io.FileOutputStream;
 import java.io.IOException;
@@ -48,13 +48,13 @@ public class SimpleCacheSpanTest extends InstrumentationTestCase {
 
   @Override
   protected void setUp() throws Exception {
-    cacheDir = TestUtil.createTempFolder(getInstrumentation().getContext());
+    cacheDir = Util.createTempDirectory(getInstrumentation().getContext(), "ExoPlayerTest");
     index = new CachedContentIndex(cacheDir);
   }
 
   @Override
   protected void tearDown() throws Exception {
-    TestUtil.recursiveDelete(cacheDir);
+    Util.recursiveDelete(cacheDir);
   }
 
   public void testCacheFile() throws Exception {

library/src/androidTest/java/com/google/android/exoplayer2/upstream/cache/SimpleCacheTest.java

@@ -18,7 +18,6 @@ package com.google.android.exoplayer2.upstream.cache;
 import android.test.InstrumentationTestCase;
 import android.test.MoreAsserts;
 import com.google.android.exoplayer2.C;
-import com.google.android.exoplayer2.testutil.TestUtil;
 import com.google.android.exoplayer2.util.Util;
 import java.io.File;
 import java.io.FileInputStream;
@@ -39,12 +38,12 @@ public class SimpleCacheTest extends InstrumentationTestCase {
 
   @Override
   protected void setUp() throws Exception {
-    this.cacheDir = TestUtil.createTempFolder(getInstrumentation().getContext());
+    cacheDir = Util.createTempDirectory(getInstrumentation().getContext(), "ExoPlayerTest");
   }
 
   @Override
   protected void tearDown() throws Exception {
-    TestUtil.recursiveDelete(cacheDir);
+    Util.recursiveDelete(cacheDir);
   }
 
   public void testCommittingOneFile() throws Exception {

library/src/androidTest/java/com/google/android/exoplayer2/util/AtomicFileTest.java

@@ -17,7 +17,6 @@
 package com.google.android.exoplayer2.util;
 
 import android.test.InstrumentationTestCase;
-import com.google.android.exoplayer2.testutil.TestUtil;
 import java.io.File;
 import java.io.IOException;
 import java.io.InputStream;
@@ -34,14 +33,14 @@ public class AtomicFileTest extends InstrumentationTestCase {
 
   @Override
   public void setUp() throws Exception {
-    tempFolder = TestUtil.createTempFolder(getInstrumentation().getContext());
+    tempFolder = Util.createTempDirectory(getInstrumentation().getContext(), "ExoPlayerTest");
     file = new File(tempFolder, "atomicFile");
     atomicFile = new AtomicFile(file);
   }
 
   @Override
   protected void tearDown() throws Exception {
-    TestUtil.recursiveDelete(tempFolder);
+    Util.recursiveDelete(tempFolder);
   }
 
   public void testDelete() throws Exception {

library/src/main/java/com/google/android/exoplayer2/util/Util.java

@@ -36,6 +36,7 @@ import com.google.android.exoplayer2.upstream.DataSource;
 import com.google.android.exoplayer2.upstream.DataSpec;
 import java.io.ByteArrayOutputStream;
 import java.io.Closeable;
+import java.io.File;
 import java.io.IOException;
 import java.io.InputStream;
 import java.lang.reflect.Method;
@@ -946,6 +947,24 @@ public final class Util {
     throw (T) t;
   }
 
+  /** Recursively deletes a directory and its content. */
+  public static void recursiveDelete(File fileOrDirectory) {
+    if (fileOrDirectory.isDirectory()) {
+      for (File child : fileOrDirectory.listFiles()) {
+        recursiveDelete(child);
+      }
+    }
+    fileOrDirectory.delete();
+  }
+
+  /** Creates an empty directory in the directory returned by {@link Context#getCacheDir()}. */
+  public static File createTempDirectory(Context context, String prefix) throws IOException {
+    File tempFile = File.createTempFile(prefix, null, context.getCacheDir());
+    tempFile.delete(); // Delete the temp file.
+    tempFile.mkdir(); // Create a directory with the same name.
+    return tempFile;
+  }
+
   /**
    * Returns the result of updating a CRC with the specified bytes in a "most significant bit first"
    * order.

testutils/src/main/java/com/google/android/exoplayer2/testutil/TestUtil.java

@@ -16,7 +16,6 @@
 package com.google.android.exoplayer2.testutil;
 
 import android.app.Instrumentation;
-import android.content.Context;
 import android.test.InstrumentationTestCase;
 import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.extractor.Extractor;
@@ -25,7 +24,6 @@ import com.google.android.exoplayer2.extractor.SeekMap;
 import com.google.android.exoplayer2.testutil.FakeExtractorInput.SimulatedIOException;
 import com.google.android.exoplayer2.util.Assertions;
 import com.google.android.exoplayer2.util.Util;
-import java.io.File;
 import java.io.IOException;
 import java.io.InputStream;
 import java.util.Arrays;
@@ -375,21 +373,4 @@ public class TestUtil {
     }
   }
 
-  public static void recursiveDelete(File fileOrDirectory) {
-    if (fileOrDirectory.isDirectory()) {
-      for (File child : fileOrDirectory.listFiles()) {
-        recursiveDelete(child);
-      }
-    }
-    fileOrDirectory.delete();
-  }
-
-  /** Creates an empty folder in the application specific cache directory. */
-  public static File createTempFolder(Context context) throws IOException {
-    File tempFolder = File.createTempFile("ExoPlayerTest", null, context.getCacheDir());
-    Assert.assertTrue(tempFolder.delete());
-    Assert.assertTrue(tempFolder.mkdir());
-    return tempFolder;
-  }
-
 }