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  1. Drools
  2. DROOLS-777

Variable length argument lists lose arguments in MVEL

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    • Icon: Bug Bug
    • Resolution: Done
    • Icon: Major Major
    • 6.3.0.Beta1
    • 6.1.0.Final
    • core engine
    • None
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      Define a class

      public class Assertion {
   public String keyword;
   public final List<String> parameters = new ArrayList<>();
   
   public Assertion(String keyword, String... params) {
	this.keyword = keyword;
	for (String param: params) {
		parameters.add(param);
	}
   }

@Override
  public String toString() {
	String result = keyword;
	for (String param: parameters) {
		result += " " + param;
	}
	return result;
}

      Now define rules

      rule "Unexpected input type when slide navigation is expected"
dialect "mvel"
    when
        not(Assertion())
    then
    	insert(new Assertion("UNEXPECTED_CONTENT", "KW1", "KW2"))
end


rule "Unexpected input type when slide navigation is expected"
dialect "mvel"
    when
        $assert: Assertion()
    then
         System.out.println($assert);
         retract($assert);
end

      Expected output:
      "UNEXPECTED_CONTENT KW1 KW2"
      Actual output:
      "UNEXPECTED_CONTENT KW1"

      I have walked it through with a debugger, and KW2 is never passed to the constructor.

      Show
      Define a class public class Assertion { public String keyword; public final List< String > parameters = new ArrayList<>(); public Assertion( String keyword, String ... params) { this .keyword = keyword; for ( String param: params) { parameters.add(param); } } @Override public String toString() { String result = keyword; for ( String param: parameters) { result += " " + param; } return result; } Now define rules rule "Unexpected input type when slide navigation is expected" dialect "mvel" when not(Assertion()) then insert( new Assertion( "UNEXPECTED_CONTENT" , "KW1" , "KW2" )) end rule "Unexpected input type when slide navigation is expected" dialect "mvel" when $ assert : Assertion() then System .out.println($ assert ); retract($ assert ); end Expected output: "UNEXPECTED_CONTENT KW1 KW2" Actual output: "UNEXPECTED_CONTENT KW1" I have walked it through with a debugger, and KW2 is never passed to the constructor.

      When I use a method with variable number of arguments (e.g., String... args) in MVEL, the first one is passed on, and the others are discarded, leading to confusing and difficult to debug bugs. It should either support this, or report a compilation error.

              mfusco@redhat.com Mario Fusco
              myrosia_jira Myroslava Dzikovska (Inactive)
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                Created:
                Updated:
                Resolved: