public void testOtherFiles2() throws Throwable {
Directory dir = newDirectory();
try {
// Create my own random file:
IndexOutput out = dir.createOutput("_a.frq", newIOContext(random()));
out.writeByte((byte) 42);
out.close();
new IndexWriter(dir, newIndexWriterConfig( TEST_VERSION_CURRENT, new MockAnalyzer(random()))).close();
assertTrue(dir.fileExists("_a.frq"));