private void givenGemFirePropertiesFile(final Properties config) {
    try {
      String name = GEMFIRE_PREFIX + "properties";
      File file = new File(getWorkingDirectory(), name);
      config.store(new FileWriter(file, false), testName.getMethodName());
      assertThat(file).isFile().exists();

      System.setProperty(PROPERTIES_FILE_PROPERTY, file.getCanonicalPath());
    } catch (IOException e) {
      throw new UncheckedIOException(e);
    }
  }
Creates a gemfire properties file in temporaryFolder:
<ol>
<li>creates gemfire.properties in {@code temporaryFolder}</li>
<li>writes config to the file</li>
<li>sets "gemfirePropertyFile" system property</li>
</ol>
geode-core/src/integrationTest/java/org/apache/geode/distributed/LocatorLauncherIntegrationTest.java