Program: 167927
Project: 167927
Buggy source:
public SimpleDataSourceOperationHandler(final String dsType){
  super("String_Node_Str",true);
  this.dsType=dsType;
  profile=new ArgumentWithValue(this,new DefaultCompleter(new CandidatesProvider(){
    @Override public List<String> getAllCandidates(    CommandContext ctx){
      return Util.getNodeNames(ctx.getModelControllerClient(),null,"String_Node_Str");
    }
  }
),"String_Node_Str"){
    @Override public boolean canAppearNext(    CommandContext ctx) throws CommandFormatException {
      if (!ctx.isDomainMode()) {
        return false;
      }
      return super.canAppearNext(ctx);
    }
  }
;
  name=new ArgumentWithValue(this,new DefaultCompleter(new DefaultCompleter.CandidatesProvider(){
    @Override public List<String> getAllCandidates(    CommandContext ctx){
      ModelControllerClient client=ctx.getModelControllerClient();
      if (client == null) {
        return Collections.emptyList();
      }
      final String profileArg;
      if (!ctx.isDomainMode()) {
        profileArg=null;
      }
 else {
        profileArg=profile.getValue(ctx.getParsedArguments());
        if (profileArg == null) {
          return Collections.emptyList();
        }
      }
      return Util.getDatasources(ctx.getModelControllerClient(),profileArg,dsType);
    }
  }
),0,"String_Node_Str"){
    @Override public boolean canAppearNext(    CommandContext ctx) throws CommandFormatException {
      if (ctx.isDomainMode() && !profile.isPresent(ctx.getParsedArguments())) {
        return false;
      }
      return super.canAppearNext(ctx);
    }
  }
;
  operation=new ArgumentWithValue(this,new CommandLineCompleter(){
    @Override public int complete(    CommandContext ctx,    String buffer,    int cursor,    List<String> candidates){
      final StringBuilder buf=new StringBuilder();
      if (ctx.isDomainMode()) {
        final String profileName=profile.getValue(ctx.getParsedArguments());
        if (profile == null) {
          return -1;
        }
        buf.append("String_Node_Str").append(profileName);
      }
      buf.append("String_Node_Str").append(dsType).append('=');
      final String dsName=name.getValue(ctx.getParsedArguments());
      if (dsName == null) {
        return -1;
      }
      buf.append(Util.escapeString(dsName,OperationRequestCompleter.ESCAPE_SELECTOR)).append(':');
      final int addressLength=buf.length();
      cursor+=addressLength;
      buf.append(buffer);
      int result=OperationRequestCompleter.INSTANCE.complete(ctx,buf.toString(),cursor,candidates) - addressLength;
      return result;
    }
  }
,1,"String_Node_Str"){
    @Override public boolean canAppearNext(    CommandContext ctx) throws CommandFormatException {
      if (ctx.isDomainMode() && !profile.isPresent(ctx.getParsedArguments())) {
        return false;
      }
      return super.canAppearNext(ctx);
    }
  }
;
  operation.addRequiredPreceding(name);
}

Fixed version (ground truth):
public SimpleDataSourceOperationHandler(final String dsType){
  super("String_Node_Str",true);
  this.dsType=dsType;
  profile=new ArgumentWithValue(this,new DefaultCompleter(new CandidatesProvider(){
    @Override public List<String> getAllCandidates(    CommandContext ctx){
      return Util.getNodeNames(ctx.getModelControllerClient(),null,"String_Node_Str");
    }
  }
),"String_Node_Str"){
    @Override public boolean canAppearNext(    CommandContext ctx) throws CommandFormatException {
      if (!ctx.isDomainMode()) {
        return false;
      }
      return super.canAppearNext(ctx);
    }
  }
;
  name=new ArgumentWithValue(this,new DefaultCompleter(new DefaultCompleter.CandidatesProvider(){
    @Override public List<String> getAllCandidates(    CommandContext ctx){
      NewModelControllerClient client=ctx.getModelControllerClient();
      if (client == null) {
        return Collections.emptyList();
      }
      final String profileArg;
      if (!ctx.isDomainMode()) {
        profileArg=null;
      }
 else {
        profileArg=profile.getValue(ctx.getParsedArguments());
        if (profileArg == null) {
          return Collections.emptyList();
        }
      }
      return Util.getDatasources(ctx.getModelControllerClient(),profileArg,dsType);
    }
  }
),0,"String_Node_Str"){
    @Override public boolean canAppearNext(    CommandContext ctx) throws CommandFormatException {
      if (ctx.isDomainMode() && !profile.isPresent(ctx.getParsedArguments())) {
        return false;
      }
      return super.canAppearNext(ctx);
    }
  }
;
  operation=new ArgumentWithValue(this,new CommandLineCompleter(){
    @Override public int complete(    CommandContext ctx,    String buffer,    int cursor,    List<String> candidates){
      final StringBuilder buf=new StringBuilder();
      if (ctx.isDomainMode()) {
        final String profileName=profile.getValue(ctx.getParsedArguments());
        if (profile == null) {
          return -1;
        }
        buf.append("String_Node_Str").append(profileName);
      }
      buf.append("String_Node_Str").append(dsType).append('=');
      final String dsName=name.getValue(ctx.getParsedArguments());
      if (dsName == null) {
        return -1;
      }
      buf.append(Util.escapeString(dsName,OperationRequestCompleter.ESCAPE_SELECTOR)).append(':');
      final int addressLength=buf.length();
      cursor+=addressLength;
      buf.append(buffer);
      int result=OperationRequestCompleter.INSTANCE.complete(ctx,buf.toString(),cursor,candidates) - addressLength;
      return result;
    }
  }
,1,"String_Node_Str"){
    @Override public boolean canAppearNext(    CommandContext ctx) throws CommandFormatException {
      if (ctx.isDomainMode() && !profile.isPresent(ctx.getParsedArguments())) {
        return false;
      }
      return super.canAppearNext(ctx);
    }
  }
;
  operation.addRequiredPreceding(name);
}