feat: add relation.type attribute

Template engine which may not have access to instanceof, can use relation.type

Author: ozum

src/pg-structure/relation/m2m-relation.ts

@@ -1,5 +1,5 @@
 import { Memoize } from "@typescript-plus/fast-memoize-decorator/dist/src";
-import { RelationNameFunctions } from "../../types/index";
+import { RelationNameFunctions, RelationType } from "../../types/index";
 import ForeignKey from "../constraint/foreign-key";
 import Table from "../entity/table";
 import Relation, { RelationConstructorArgs, RelationWithout } from "../base/relation";
@@ -70,6 +70,12 @@ export default class M2MRelation extends Relation {
     this.targetForeignKey = args.targetForeignKey;
   }
 
+  /**
+   * Type of the relation, which is `m2m` for [[M2MRelation]].
+   * For TypeScript it is enum of `RelationType.M2M`.
+   */
+  public readonly type = RelationType.M2M;
+
   /**
    * Whether the relation targets to many. Since, many to many relations targets many, this is `true`.
    */

src/pg-structure/relation/m2o-relation.ts

@@ -1,5 +1,5 @@
 import { Memoize } from "@typescript-plus/fast-memoize-decorator/dist/src";
-import { RelationNameFunctions } from "../../types/index";
+import { RelationNameFunctions, RelationType } from "../../types/index";
 import Relation, { RelationConstructorArgs, RelationWithout } from "../base/relation";
 import Table from "../entity/table";
 import ForeignKey from "../constraint/foreign-key";
@@ -43,6 +43,12 @@ export default class M2ORelation extends Relation {
     this.foreignKey = args.foreignKey;
   }
 
+  /**
+   * Type of the relation, which is `m2o` for [[M2ORelation]].
+   * For TypeScript it is enum of `RelationType.M2O`.
+   */
+  public readonly type = RelationType.M2O;
+
   /**
    * Whether the relation targets to many. Since, many to one relations targets single, this is `true`.
    */

src/pg-structure/relation/o2m-relation.ts

@@ -1,5 +1,5 @@
 import { Memoize } from "@typescript-plus/fast-memoize-decorator/dist/src";
-import { RelationNameFunctions } from "../../types/index";
+import { RelationNameFunctions, RelationType } from "../../types/index";
 import Relation, { RelationConstructorArgs, RelationWithout } from "../base/relation";
 import Table from "../entity/table";
 import ForeignKey from "../constraint/foreign-key";
@@ -41,6 +41,12 @@ export default class O2MRelation extends Relation {
     this.foreignKey = args.foreignKey;
   }
 
+  /**
+   * Type of the relation, which is `o2m` for [[O2MRelation]].
+   * For TypeScript it is enum of `RelationType.O2M`.
+   */
+  public readonly type = RelationType.O2M;
+
   /**
    * Whether the relation targets to many. Since, one to many relations targets many, this is `true`.
    */

src/types/index.ts

@@ -5,12 +5,24 @@ import M2MRelation from "../pg-structure/relation/m2m-relation";
 
 export * from "./json";
 
+/**
+ * Type of the numeric type.
+ */
 export const enum NumericType {
   Integer = "Integer",
   Exact = "Exact",
   Floating = "Floating",
 }
 
+/**
+ * Type of the relation.
+ */
+export const enum RelationType {
+  O2M = "o2m",
+  M2M = "m2m",
+  M2O = "m2o",
+}
+
 /**
  * Actions performed when the data in the foreign key referenced columns is changed.
  */

test/relation/m2m-relation.test.ts

@@ -27,6 +27,10 @@ beforeAll(async () => {
 });
 
 describe("M2MRelation", () => {
+  it("should be type of 'm2m'.", () => {
+    expect(studentTable.m2mRelations[0].type).toEqual("m2m");
+  });
+
   it("should be toMany.", () => {
     expect(studentTable.m2mRelations[0].toMany).toEqual(true);
   });

test/relation/m2o-relation.test.ts

@@ -25,6 +25,10 @@ beforeAll(async () => {
 });
 
 describe("M2ORelation", () => {
+  it("should be type of 'm2o'.", () => {
+    expect(messageTable.m2oRelations[0].type).toEqual("m2o");
+  });
+
   it("should not be toMany.", () => {
     expect(messageTable.m2oRelations[0].toMany).toEqual(false);
   });

test/relation/o2m-relation.test.ts

@@ -32,6 +32,10 @@ beforeAll(async () => {
 });
 
 describe("O2MRelation", () => {
+  it("should be type of 'o2m'.", () => {
+    expect(studentTable.o2mRelations[0].type).toEqual("o2m");
+  });
+
   it("should be toMany.", () => {
     expect(studentTable.o2mRelations[0].toMany).toEqual(true);
   });