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// or more contributor license agreements.  See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership.  The SFC licenses this file
// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
// with the License.  You may obtain a copy of the License at
//
//   http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing,
// software distributed under the License is distributed on an
// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
// KIND, either express or implied.  See the License for the
// specific language governing permissions and limitations
// under the License.

package org.openqa.selenium.grid.config;

import com.google.common.collect.ImmutableList;

import java.util.List;
import java.util.Locale;
import java.util.Objects;
import java.util.Optional;

/**
 * Exposes environment variables as config settings by mapping
 * "section.option" to "SECTION_OPTION". Dashes and periods in the options
 * are converted to underscores, and all characters are upper-cased assuming
 * a US English locale.
 */
public class EnvConfig implements Config {

  @Override
  public Optional<List<String>> getAll(String section, String option) {
    Objects.requireNonNull(section, "Section name not set");
    Objects.requireNonNull(option, "Option name not set");

    String key = String.format("%s_%s", section, option)
      .toUpperCase(Locale.US)
      .replace("-", "_")
      .replace(".", "_");

    return Optional.ofNullable(System.getenv().get(key)).map(ImmutableList::of);
  }
}

@@ -1633,59 +1633,237 @@
     
-return Optional.ofNullable(System.getenv().get(key)
+String value = System.getenv().get(key);%0A    if (value == null) %7B%0A      return Optional.empty();%0A    %7D%0A%0A    if (value.startsWith(%22$%22)) %7B%0A      value = System.getenv(value.substring(1));%0A    %7D%0A%0A    return Optional.ofNullable(value
 ).ma

Allow EnvConfig to use the values of other env variables