code: private static EnvVars inherit(@CheckForNull String[] env) {
          // convert String[] to Map first
          EnvVars m = new EnvVars();
          if(env!=null) {
              for (String e : env) {
                  int index = e.indexOf('=');
                  m.put(e.substring(0,index), e.substring(index+1));
              }
          }
          // then do the inheritance
          return inherit(m);
      }
docs: Expands the list of environment variables by inheriting current env variables.