Incorrect Result in Collection Attribute Evaluation with Circular `when` Condition and Circular Evaluation

[Idriss Riouak]

Issue Summary:

The collection attributes in JastAdd are computing incorrect results when the when condition is/depends on a circular attribute and the attributes are called within a circular evaluation. This issue arises specifically when using the --safeLazy option, as the attribute is cached too early.

The problem appears only when using --safeLazy.

Example:

Given the following RAG specification:

//Grammar: Root;
//Options: --rewrite=cnta --visitCheck=false --safelazy 

syn Set<Integer> Root.numbers() circular [new HashSet<Integer>()]  {
    return collectNumbers();
}

coll Set<Integer> Root.collectNumbers() [new HashSet<Integer>()];
Root contributes 42 when alwaysTrue() to Root.collectNumbers();

syn boolean Root.alwaysTrue() = circ() == 4;

syn Integer Root.circ() circular [0] {
    Integer temp = circ()+1;
    System.out.println("temp: " + temp);
    return Math.min(4, temp);
}

The expected output of the following Java program

public class Test {
  public static void main(String[] args) {
    Root r = new Root();
    System.out.println(r.numbers());
  }
}

should be:

temp: 1
temp: 2
temp: 3
temp: 4
temp: 5
temp: 5
[42]

The actual result is:

temp: 1
[]

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