Support for subquery filtering

* Added new QueryField constructors to handle generating subquery filters

Author: jongpie

src/classes/SobjectQueryBuilder.cls

@@ -309,6 +309,19 @@ public class SobjectQueryBuilder extends Soql {
         return childQuery;
     }
 
+    public String getSubquery(Schema.SobjectField childToParentRelationshipField) {
+        String subquery = '(SELECT ' + childToParentRelationshipField
+            + ' FROM ' + this.sobjectType
+            + super.doGetUsingScopeString()
+            + super.doGetWhereClauseString()
+            + super.doGetOrderByString()
+            + super.doGetLimitCountString()
+            + ')';
+
+        System.debug(LoggingLevel.FINEST, subquery);
+        return subquery;
+    }
+
     public String getSearchQuery() {
         String sobjectTypeOptions = super.doGetQueryFieldString()
             + super.doGetWhereClauseString()

src/classes/Soql.cls

@@ -401,6 +401,16 @@ public abstract class Soql implements Comparable {
             this.filterString = queryField + ' ' + Soql.getOperatorValue(operator) + ' ' + formattedValue;
         }
 
+        public QueryFilter(Schema.SobjectType childSobjectType, Boolean inOrNotIn, Schema.SobjectField lookupFieldOnChildSobject) {
+            this.operator     = inOrNotIn ? Soql.Operator.IS_IN : Soql.Operator.IS_NOT_IN;
+            this.filterString = 'Id ' + Soql.getOperatorValue(this.operator) + ' (SELECT ' + lookupFieldOnChildSobject + ' FROM ' + childSobjectType + ')';
+        }
+
+        public QueryFilter(SobjectQueryBuilder childSobjectQueryBuilder, Boolean inOrNotIn, Schema.SobjectField lookupFieldOnChildSobject) {
+            this.operator     = inOrNotIn ? Soql.Operator.IS_IN : Soql.Operator.IS_NOT_IN;
+            this.filterString = 'Id ' + Soql.getOperatorValue(this.operator) + ' ' + childSobjectQueryBuilder.getSubquery(lookupFieldOnChildSobject);
+        }
+
         public Integer compareTo(Object compareTo) {
             QueryFilter compareToQueryFilter = (QueryFilter)compareTo;