Issue 4181 - Fix FilterEngineTest tests

libadblockplus-android-tests/src/org/adblockplus/libadblockplus/tests/BaseJsTest.java

Index: libadblockplus-android-tests/src/org/adblockplus/libadblockplus/tests/BaseJsTest.java
diff --git a/libadblockplus-android-tests/src/org/adblockplus/libadblockplus/tests/BaseJsTest.java b/libadblockplus-android-tests/src/org/adblockplus/libadblockplus/tests/BaseJsTest.java
index 544fcb741ad70fafab905f8f2b04a6de673ecda8..56c1431e8c6341b319dafe6c23d3f36cb958a5db 100644
--- a/libadblockplus-android-tests/src/org/adblockplus/libadblockplus/tests/BaseJsTest.java
+++ b/libadblockplus-android-tests/src/org/adblockplus/libadblockplus/tests/BaseJsTest.java
@@ -18,16 +18,26 @@
 package org.adblockplus.libadblockplus.tests;
 
 import org.adblockplus.libadblockplus.AppInfo;
+import org.adblockplus.libadblockplus.FileSystemUtils;
 import org.adblockplus.libadblockplus.JsEngine;
-import org.adblockplus.libadblockplus.LazyLogSystem;
 import org.adblockplus.libadblockplus.ThrowingWebRequest;
 
 import android.content.Context;
 import android.test.InstrumentationTestCase;
 
+import java.io.File;
+
 public abstract class BaseJsTest extends InstrumentationTestCase
 {
   protected JsEngine jsEngine;
+  protected File tmpFileSystemPath;
+
+  protected File buildTmpFileSystemPath()
+  {
+    File tmpFileSystemPath = FileSystemUtils.generateUniqueFile(null, ".fs", getContext().getCacheDir());
+    tmpFileSystemPath.mkdirs();
+    return tmpFileSystemPath;
+  }
 
   @Override
   protected void setUp() throws Exception
@@ -36,10 +46,30 @@ public abstract class BaseJsTest extends InstrumentationTestCase
 
     jsEngine = new JsEngine(AppInfo.builder().build());
     jsEngine.setDefaultLogSystem();
-    jsEngine.setDefaultFileSystem(getContext().getFilesDir().getAbsolutePath());
+
+    // we need to generate new file system path in order
+    // not to have JsEngine state from the previous test
+    tmpFileSystemPath = buildTmpFileSystemPath();
+    jsEngine.setDefaultFileSystem(tmpFileSystemPath.getAbsolutePath());
     jsEngine.setWebRequest(new ThrowingWebRequest());
   }
 
+  protected void cleanupFileSystem()
+  {
+    if (tmpFileSystemPath != null && tmpFileSystemPath.exists())
+    {
+      FileSystemUtils.delete(tmpFileSystemPath);
+      tmpFileSystemPath = null;
+    }
+  }
+
+  @Override
+  protected void tearDown() throws Exception
+  {
+    cleanupFileSystem();
+    super.tearDown();
+  }
+
   protected Context getContext()
   {
     return getInstrumentation().getTargetContext();