[BUG] Fail to visit multi-nested for some QueryBuilder

[wdongyu]

Describe the bug

A way to visit all nested QueryBuilders from source have been implemented before, but it has some flaws.

For example, in BooleanQueryBuilder, the visit method first accept the current BooleanQueryBuilder, and then go down the tree by calling its nested must/should/filter QueryBuilder's visit methods. That's expected.

    public void visit(QueryBuilderVisitor visitor) {
        visitor.visit(this);
        if (mustClauses.isEmpty() == false) {
            QueryBuilderVisitor subVisitor = visitor.getChildVisitor(Occur.MUST);
            for (QueryBuilder mustClause : mustClauses) {
                mustClause.visit(subVisitor);
            }
        }
        if (shouldClauses.isEmpty() == false) {
            QueryBuilderVisitor subVisitor = visitor.getChildVisitor(Occur.SHOULD);
            for (QueryBuilder shouldClause : shouldClauses) {
                shouldClause.visit(subVisitor);
            }
        }
        if (mustNotClauses.isEmpty() == false) {
            QueryBuilderVisitor subVisitor = visitor.getChildVisitor(Occur.MUST_NOT);
            for (QueryBuilder mustNotClause : mustNotClauses) {
                mustNotClause.visit(subVisitor);
            }
        }
        if (filterClauses.isEmpty() == false) {
            QueryBuilderVisitor subVisitor = visitor.getChildVisitor(Occur.FILTER);
            for (QueryBuilder filterClause : filterClauses) {
                filterClause.visit(subVisitor);
            }
        }
    }

But for BoostingQueryBuilder, the visit method also first accept the current BoostingQueryBuilder, but next accept the nest positive/negative QueryBuiler, instead of visiting them:

  public void visit(QueryBuilderVisitor visitor) {
      visitor.accept(this);
      if (positiveQuery != null) {
          visitor.getChildVisitor(BooleanClause.Occur.MUST).accept(positiveQuery);
      }
      if (negativeQuery != null) {
          visitor.getChildVisitor(BooleanClause.Occur.SHOULD).accept(negativeQuery);
      }
  }

We should go down the tree by calling the nested QueryBuilder's visit method, like this:

    public void visit(QueryBuilderVisitor visitor) {
        visitor.accept(this);
        if (positiveQuery != null) {
            positiveQuery.visit(visitor.getChildVisitor(BooleanClause.Occur.MUST));

            // visitor.getChildVisitor(BooleanClause.Occur.MUST).accept(positiveQuery);
        }
        if (negativeQuery != null) {
            negativeQuery.visit(visitor.getChildVisitor(BooleanClause.Occur.SHOULD));
          
            // visitor.getChildVisitor(BooleanClause.Occur.SHOULD).accept(negativeQuery);
        }
    }

Related component

Search:Query Capabilities

To Reproduce

change and run the following testcase in BoostingQueryBuilder, it will success but should fail in deed:

    public void testVisit() {
      BoostingQueryBuilder builder = new BoostingQueryBuilder(
          new BoolQueryBuilder()
              .must(new TermQueryBuilder("unmapped_field1", "value1"))
              .should(new TermQueryBuilder("unmapped_field2", "value2")),
            
          new TermQueryBuilder(KEYWORD_FIELD_NAME, "other_value")
      );

      List<QueryBuilder> visitedQueries = new ArrayList<>();
      builder.visit(createTestVisitor(visitedQueries));

        assertEquals(3, visitedQueries.size());
    }

Expected behavior

change and run the following testcase in BoostingQueryBuilder, it should success:

    public void testVisit() {
      BoostingQueryBuilder builder = new BoostingQueryBuilder(
          new BoolQueryBuilder()
              .must(new TermQueryBuilder("unmapped_field1", "value1"))
              .should(new TermQueryBuilder("unmapped_field2", "value2")),
            
          new TermQueryBuilder(KEYWORD_FIELD_NAME, "other_value")
      );

      List<QueryBuilder> visitedQueries = new ArrayList<>();
      builder.visit(createTestVisitor(visitedQueries));

        assertEquals(5, visitedQueries.size());  // change 3 -> 5
    }

Additional Details

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• OS: [e.g. iOS]
• Version [e.g. 22]

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[peternied]

[Triage - attendees 1 2 3 4 5 6
@wdongyu Thanks for creating this detailed issue and a pull request to address the issue.