Use different directory names in directory tests

runtime/bin/directory_test.cc

 // Copyright (c) 2016, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "bin/directory.h"
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "vm/isolate.h"
 #include "vm/thread.h"
 #include "vm/unit_test.h"
@@ skipping 66 matching lines @@
   const char* new_current = dart::bin::Directory::Current();
   EXPECT_NOTNULL(new_current);
 
   EXPECT_NOTNULL(strstr(new_current, system_temp));
 
   EXPECT(dart::bin::Directory::SetCurrent(current));
 }
 
 
 TEST_CASE(DirectoryCreateDelete) {
-  const char* kTempDirName = "test_name";
+  const char* kTempDirName = "create_delete_test_name";
 
   const char* system_temp = dart::bin::Directory::SystemTemp();
   EXPECT_NOTNULL(system_temp);
 
   const intptr_t name_len =
       snprintf(NULL, 0, "%s/%s", system_temp, kTempDirName);
   ASSERT(name_len > 0);
   char* name = new char[name_len + 1];
   snprintf(name, name_len + 1, "%s/%s", system_temp, kTempDirName);
 
   // Make a directory.
   EXPECT(dart::bin::Directory::Create(name));
 
   // Make sure it exists.
   dart::bin::Directory::ExistsResult r = dart::bin::Directory::Exists(name);
   EXPECT_EQ(dart::bin::Directory::EXISTS, r);
 
   // Cleanup.
   EXPECT(dart::bin::Directory::Delete(name, false));
   delete[] name;
 }
 
 
 TEST_CASE(DirectoryRename) {
-  const char* kTempDirName = "test_name";
+  const char* kTempDirName = "rename_test_name";
 
   const char* system_temp = dart::bin::Directory::SystemTemp();
   EXPECT_NOTNULL(system_temp);
 
   const intptr_t name_len =
       snprintf(NULL, 0, "%s/%s", system_temp, kTempDirName);
   ASSERT(name_len > 0);
   char* name = new char[name_len + 1];
   snprintf(name, name_len + 1, "%s/%s", system_temp, kTempDirName);
 
@@ skipping 18 matching lines @@
 
   r = dart::bin::Directory::Exists(name);
   EXPECT_EQ(dart::bin::Directory::DOES_NOT_EXIST, r);
 
   EXPECT(dart::bin::Directory::Delete(new_name, false));
   delete[] name;
   delete[] new_name;
 }
 
 }  // namespace dart