Merge pull request apex-enterprise-patterns#402 from apex-enterprise-patterns/rebase-pr-137

Redux of PR apex-enterprise-patterns#137 - rebased against latest master and merge conflicts resolved along with the two outstanding comments on the prior PR

Author: daveespo

sfdx-source/apex-common/main/classes/fflib_QueryFactory.cls

@@ -84,7 +84,7 @@ public class fflib_QueryFactory { //No explicit sharing declaration - inherit fr
 	private Schema.ChildRelationship relationship;
 	private Map<Schema.ChildRelationship, fflib_QueryFactory> subselectQueryMap;
 
-	private String getFieldPath(String fieldName){
+	private String getFieldPath(String fieldName, Schema.sObjectType relatedSObjectType){
 		if(!fieldName.contains('.')){ //single field
 			Schema.SObjectField token = fflib_SObjectDescribe.getDescribe(table).getField(fieldName.toLowerCase());
 			if(token == null)
@@ -107,8 +107,21 @@ public class fflib_QueryFactory { //No explicit sharing declaration - inherit fr
 				fflib_SecurityUtils.checkFieldIsReadable(lastSObjectType, token);
 			}
 
-			if(token != null && i.hasNext() && tokenDescribe.getSoapType() == Schema.SoapType.ID){
-				lastSObjectType = tokenDescribe.getReferenceTo()[0]; //if it's polymorphic doesn't matter which one we get
+			if (token != null && i.hasNext() && tokenDescribe.getSoapType() == Schema.SoapType.ID) {
+				List<Schema.sObjectType> relatedObjs = tokenDescribe.getReferenceTo(); //if it's polymorphic, it matters which one we use - i.e. Lead.Owner is GROUP|USER and each has different fields.
+
+				if (relatedObjs.size() == 1 || relatedSObjectType == null) {
+					lastSObjectType = relatedObjs[0]; //caller did not specify the one to use or there's only one so use the first one
+				}
+				else{
+					for (Schema.sObjectType sot : relatedObjs) {
+						if (fflib_SObjectDescribe.getDescribe(sot).getDescribe().getSObjectType() == relatedSObjectType) {
+							lastSObjectType = sot;
+							break;
+						}
+					}
+				}
+
 				fieldPath.add(tokenDescribe.getRelationshipName());
 			}else if(token != null && !i.hasNext()){
 				fieldPath.add(tokenDescribe.getName());
@@ -122,6 +135,10 @@ public class fflib_QueryFactory { //No explicit sharing declaration - inherit fr
 
 		return String.join(fieldPath,'.');
 	}
+	
+	private String getFieldPath(String fieldName) {
+		return this.getFieldPath(fieldName, null);
+	}
 
 	@TestVisible
 	private static String getFieldTokenPath(Schema.SObjectField field){
@@ -197,16 +214,27 @@ public class fflib_QueryFactory { //No explicit sharing declaration - inherit fr
 		this.sortSelectFields = doSort;
 		return this;
 	}
-	
 	/**
 	 * Selects a single field from the SObject specified in {@link #table}.
 	 * Selecting fields is idempotent, if this field is already selected calling this method will have no additional impact.
 	 * @param fieldName the API name of the field to add to the query's SELECT clause.
 	 **/
 	public fflib_QueryFactory selectField(String fieldName){ 		
-		fields.add( getFieldPath(fieldName) );
+		fields.add( getFieldPath(fieldName, null) );
+		return this;
+	}
+
+	/**
+		* Selects a single field from the SObject specified in {@link #table}.
+		* Selecting fields is idempotent, if this field is already selected calling this method will have no additional impact.
+		* @param fieldName the API name of the field to add to the query's SELECT clause.
+		* @param relatedSObjectType the related sObjectType to resolve polymorphic object fields.
+	 **/
+	public fflib_QueryFactory selectField(String fieldName, Schema.sOBjectType relatedObjectType) {
+		fields.add(getFieldPath(fieldName, relatedObjectType));
 		return this;
-	} 
+	}
+	
 	/**
 	 * Selects a field, avoiding the possible ambiguity of String API names.
 	 * @see #selectField(String)
@@ -760,6 +788,7 @@ public class fflib_QueryFactory { //No explicit sharing declaration - inherit fr
 			this.setMessage( 'Invalid field \''+fieldName+'\' for object \''+objectType+'\'' );
 		}
 	}
+
 	public class InvalidFieldSetException extends Exception{}
 	public class NonReferenceFieldException extends Exception{}
 	public class InvalidSubqueryRelationshipException extends Exception{}	

sfdx-source/apex-common/main/classes/fflib_SObjectSelector.cls

@@ -380,11 +380,13 @@ public abstract with sharing class fflib_SObjectSelector
      public void configureQueryFactoryFields(fflib_QueryFactory queryFactory, String relationshipFieldPath)
      {
 	// Add fields from selector prefixing the relationship path		
-	for(SObjectField field : getSObjectFieldList())		
-	queryFactory.selectField(relationshipFieldPath + '.' + field.getDescribe().getName());
-	// Automatically select the CurrencyIsoCode for MC orgs (unless the object is a known exception to the rule)
-        if(UserInfo.isMultiCurrencyOrganization() && CURRENCY_ISO_CODE_ENABLED)
-            queryFactory.selectField(relationshipFieldPath+'.CurrencyIsoCode');		
+		for(SObjectField field : getSObjectFieldList()) {
+			queryFactory.selectField(relationshipFieldPath + '.' + field.getDescribe().getName(), this.getSObjectType());
+		}
+		// Automatically select the CurrencyIsoCode for MC orgs (unless the object is a known exception to the rule)
+		if(UserInfo.isMultiCurrencyOrganization() && CURRENCY_ISO_CODE_ENABLED){
+			queryFactory.selectField(relationshipFieldPath+'.CurrencyIsoCode');
+		}
      }
 
     /**

sfdx-source/apex-common/test/classes/fflib_SObjectSelectorTest.cls

@@ -474,5 +474,85 @@ private with sharing class fflib_SObjectSelectorTest
 			return null;
 		}		
 		return testUser;
+	}
+
+	@isTest
+	static void testPolymorphicSelectWithRelatedType() {
+		//Given		
+
+		Testfflib_CampaignMemberSelector cmSelector = new Testfflib_CampaignMemberSelector();
+		fflib_QueryFactory qf = cmSelector.newQueryFactory();
+		new Testfflib_LeadSelector().configureQueryFactoryFields(qf, 'Lead');
+		new Testfflib_UserSelector().configureQueryFactoryFields(qf, 'Lead.Owner');
+
+
+		Set<String> expectedSelectFields = new Set<String>{
+				'Id', 'Status', 'Lead.Id', 'Lead.OwnerId', 'Lead.Owner.Id', 'Lead.Owner.UserRoleId'
+		};
+		if (UserInfo.isMultiCurrencyOrganization()) {
+			expectedSelectFields.add('CurrencyIsoCode');
+		}
+
+		//When
+		String soql = qf.toSOQL();
+
+		//Then
+		Pattern soqlPattern = Pattern.compile('SELECT (.*) FROM CampaignMember ORDER BY CreatedDate ASC NULLS FIRST ');
+		Matcher soqlMatcher = soqlPattern.matcher(soql);
+		soqlMatcher.matches();
+
+		List<String> actualSelectFields = soqlMatcher.group(1).deleteWhiteSpace().split(',');
+		System.assertEquals(expectedSelectFields, new Set<String>(actualSelectFields));
+	}
+
+	private class Testfflib_CampaignMemberSelector extends fflib_SObjectSelector {
+		public Testfflib_CampaignMemberSelector() {
+			super();
+		}
+
+		public List<Schema.SObjectField> getSObjectFieldList() {
+			return new List<Schema.SObjectField>{
+					CampaignMember.Id,
+					CampaignMember.Status
+			};
+		}
+
+		public Schema.SObjectType getSObjectType() {
+			return CampaignMember.sObjectType;
+		}
+	}
+
+	private class Testfflib_UserSelector extends fflib_SObjectSelector {
+		public Testfflib_UserSelector() {
+			super();
+		}
+
+		public List<Schema.SObjectField> getSObjectFieldList() {
+			return new List<Schema.SObjectField>{
+					User.UserRoleId,
+					User.Id
+			};
+		}
+
+		public Schema.SObjectType getSObjectType() {
+			return User.sObjectType;
+		}
+	}
+
+	private class Testfflib_LeadSelector extends fflib_SObjectSelector {
+		public Testfflib_LeadSelector() {
+			super();
+		}
+
+		public List<Schema.SObjectField> getSObjectFieldList() {
+			return new List<Schema.SObjectField>{
+					Lead.OwnerId,
+					Lead.Id
+			};
+		}
+
+		public Schema.SObjectType getSObjectType() {
+			return Lead.sObjectType;
+		}
 	}	
 }