Add static Relation.isOneToOne(), Relation.isChildToParent() & Relation.isParentToChild()

lib/model/graph/ModelGraphBuilder.js

@@ -76,7 +76,7 @@ class ModelGraphBuilder {
 
       const relation = node.modelClass.getRelation(relationName);
 
-      if (relation.isOneToOne()) {
+      if (relation.constructor.isOneToOne()) {
         this._buildNode(relation.relatedModelClass, relatedObjects, node, relation);
       } else {
         this._buildNodes(relation.relatedModelClass, relatedObjects, node, relation);

lib/model/graph/ModelGraphNode.js

@@ -187,7 +187,7 @@ class ModelGraphNode {
   _createDataPath() {
     if (this.parentEdge === null) {
       return [];
-    } else if (this.parentEdge.relation.isOneToOne()) {
+    } else if (this.parentEdge.relation.constructor.isOneToOne()) {
       return [...this.parentNode.dataPath, this.relationName];
     } else {
       return [...this.parentNode.dataPath, this.relationName, this.indexInRelation];

lib/model/modelSet.js

@@ -75,7 +75,7 @@ function setFast(model, obj) {
 function setRelated(model, relation, models) {
   relation = ensureRelation(model, relation);
 
-  if (relation.isOneToOne()) {
+  if (relation.constructor.isOneToOne()) {
     if (Array.isArray(models)) {
       if (models.length === 0) {
         model[relation.name] = null;
@@ -101,7 +101,7 @@ function setRelated(model, relation, models) {
 function appendRelated(model, relation, models) {
   relation = ensureRelation(model, relation);
 
-  if (!model[relation.name] || relation.isOneToOne()) {
+  if (!model[relation.name] || relation.constructor.isOneToOne()) {
     return model.$setRelated(relation, models);
   } else {
     if (Array.isArray(models)) {

lib/queryBuilder/join/JoinResultParser.js

@@ -70,7 +70,7 @@ class JoinResultParser {
     const model = tableNode.modelClass.fromDatabaseJson(row);
 
     for (const childNode of tableNode.childNodes) {
-      if (childNode.relation.isOneToOne()) {
+      if (childNode.relation.constructor.isOneToOne()) {
         model[childNode.relationProperty] = null;
       } else {
         model[childNode.relationProperty] = [];
@@ -82,7 +82,7 @@ class JoinResultParser {
 
   _addToParent(tableNode, model, parentModel) {
     if (tableNode.parentNode) {
-      if (tableNode.relation.isOneToOne()) {
+      if (tableNode.relation.constructor.isOneToOne()) {
         parentModel[tableNode.relationProperty] = model;
       } else {
         parentModel[tableNode.relationProperty].push(model);

lib/relations/Relation.js

@@ -78,7 +78,15 @@ class Relation {
       : this.joinTableModelClass;
   }
 
-  isOneToOne() {
+  static isOneToOne() {
+    return false;
+  }
+
+  static isChildToParent() {
+    return false;
+  }
+
+  static isParentToChild() {
     return false;
   }
 

lib/relations/RelationFindOperation.js

@@ -25,7 +25,7 @@ class RelationFindOperation extends FindOperation {
   }
 
   onAfter2(_, related) {
-    const isOneToOne = this.relation.isOneToOne();
+    const isOneToOne = this.relation.constructor.isOneToOne();
 
     if (this.assignResultToOwner && this.owner.isModels) {
       const owners = this.owner.modelArray;
@@ -61,7 +61,7 @@ class RelationFindOperation extends FindOperation {
   }
 
   onAfter3(builder, related) {
-    const isOneToOne = this.relation.isOneToOne();
+    const isOneToOne = this.relation.constructor.isOneToOne();
     const intOpt = builder.internalOptions();
 
     if (!intOpt.keepImplicitJoinProps) {

lib/relations/belongsToOne/BelongsToOneRelation.js

@@ -7,7 +7,11 @@ const { BelongsToOneRelateOperation } = require('./BelongsToOneRelateOperation')
 const { BelongsToOneUnrelateOperation } = require('./BelongsToOneUnrelateOperation');
 
 class BelongsToOneRelation extends Relation {
-  isOneToOne() {
+  static isOneToOne() {
+    return true;
+  }
+
+  static isChildToParent() {
     return true;
   }
 

lib/relations/hasMany/HasManyRelation.js

@@ -6,6 +6,10 @@ const { HasManyRelateOperation } = require('./HasManyRelateOperation');
 const { HasManyUnrelateOperation } = require('./HasManyUnrelateOperation');
 
 class HasManyRelation extends Relation {
+  static isParentToChild() {
+    return true;
+  }
+
   insert(_, owner) {
     return new HasManyInsertOperation('insert', {
       relation: this,

lib/relations/hasOne/HasOneRelation.js

@@ -3,7 +3,7 @@
 const { HasManyRelation } = require('../hasMany/HasManyRelation');
 
 class HasOneRelation extends HasManyRelation {
-  isOneToOne() {
+  static isOneToOne() {
     return true;
   }
 }

lib/relations/hasOneThrough/HasOneThroughRelation.js

@@ -3,7 +3,7 @@
 const { ManyToManyRelation } = require('../manyToMany/ManyToManyRelation');
 
 class HasOneThroughRelation extends ManyToManyRelation {
-  isOneToOne() {
+  static isOneToOne() {
     return true;
   }
 }

lib/relations/manyToMany/ManyToManyRelation.js

@@ -26,6 +26,10 @@ const { ManyToManyDeleteOperation } = require('./delete/ManyToManyDeleteOperatio
 const { ManyToManyDeleteSqliteOperation } = require('./delete/ManyToManyDeleteSqliteOperation');
 
 class ManyToManyRelation extends Relation {
+  static isParentToChild() {
+    return true;
+  }
+
   setMapping(mapping) {
     const retVal = super.setMapping(mapping);
 

lib/relations/manyToMany/find/ManyToManyFindOperation.js

@@ -40,7 +40,7 @@ class ManyToManyFindOperation extends RelationFindOperation {
   }
 
   onAfter2(_, related) {
-    const isOneToOne = this.relation.isOneToOne();
+    const isOneToOne = this.relation.constructor.isOneToOne();
 
     if (this.assignResultToOwner && this.owner.isModels) {
       const owners = this.owner.modelArray;