feat: support self relations

package.json

@@ -1,6 +1,6 @@
 {
     "name": "zenstack-monorepo",
-    "version": "1.0.0-alpha.57",
+    "version": "1.0.0-alpha.58",
     "description": "",
     "scripts": {
         "build": "pnpm -r build",

packages/language/package.json

@@ -1,6 +1,6 @@
 {
     "name": "@zenstackhq/language",
-    "version": "1.0.0-alpha.57",
+    "version": "1.0.0-alpha.58",
     "displayName": "ZenStack modeling language compiler",
     "description": "ZenStack modeling language compiler",
     "homepage": "https://zenstack.dev",

packages/next/package.json

@@ -1,6 +1,6 @@
 {
     "name": "@zenstackhq/next",
-    "version": "1.0.0-alpha.57",
+    "version": "1.0.0-alpha.58",
     "displayName": "ZenStack Next.js integration",
     "description": "ZenStack Next.js integration",
     "homepage": "https://zenstack.dev",

packages/plugins/react/package.json

@@ -1,7 +1,7 @@
 {
     "name": "@zenstackhq/react",
     "displayName": "ZenStack plugin and runtime for ReactJS",
-    "version": "1.0.0-alpha.57",
+    "version": "1.0.0-alpha.58",
     "description": "ZenStack plugin and runtime for ReactJS",
     "main": "index.js",
     "repository": {

packages/plugins/trpc/package.json

@@ -1,7 +1,7 @@
 {
     "name": "@zenstackhq/trpc",
     "displayName": "ZenStack plugin for tRPC",
-    "version": "1.0.0-alpha.57",
+    "version": "1.0.0-alpha.58",
     "description": "ZenStack plugin for tRPC",
     "main": "index.js",
     "repository": {

packages/runtime/package.json

@@ -1,7 +1,7 @@
 {
     "name": "@zenstackhq/runtime",
     "displayName": "ZenStack Runtime Library",
-    "version": "1.0.0-alpha.57",
+    "version": "1.0.0-alpha.58",
     "description": "Runtime of ZenStack for both client-side and server-side environments.",
     "repository": {
         "type": "git",

packages/schema/package.json

@@ -3,7 +3,7 @@
     "publisher": "zenstack",
     "displayName": "ZenStack Language Tools",
     "description": "A toolkit for building secure CRUD apps with Next.js + Typescript",
-    "version": "1.0.0-alpha.57",
+    "version": "1.0.0-alpha.58",
     "author": {
         "name": "ZenStack Team"
     },

packages/schema/src/language-server/validator/datamodel-validator.ts

@@ -118,8 +118,13 @@ export default class DataModelValidator implements AstValidator<DataModel> {
         }
 
         if (!fields || !references) {
-            if (accept) {
-                accept('error', `Both "fields" and "references" must be provided`, { node: relAttr });
+            if (this.isSelfRelation(field, name)) {
+                // self relations are partial
+                // https://www.prisma.io/docs/concepts/components/prisma-schema/relations/self-relations
+            } else {
+                if (accept) {
+                    accept('error', `Both "fields" and "references" must be provided`, { node: relAttr });
+                }
             }
         } else {
             // validate "fields" and "references" typing consistency
@@ -157,6 +162,33 @@ export default class DataModelValidator implements AstValidator<DataModel> {
         return { attr: relAttr, name, fields, references, valid };
     }
 
+    private isSelfRelation(field: DataModelField, relationName?: string) {
+        if (field.type.reference?.ref === field.$container) {
+            // field directly references back to its type
+            return true;
+        }
+
+        if (relationName) {
+            // field's relation points to another type, and that type's opposite relation field
+            // points back
+            const oppositeModelFields = field.type.reference?.ref?.fields as DataModelField[];
+            if (oppositeModelFields) {
+                for (const oppositeField of oppositeModelFields) {
+                    const { name: oppositeRelationName } = this.parseRelation(oppositeField);
+                    if (
+                        oppositeRelationName === relationName &&
+                        oppositeField.type.reference?.ref === field.$container
+                    ) {
+                        // found an opposite relation field that points back to this field's type
+                        return true;
+                    }
+                }
+            }
+        }
+
+        return false;
+    }
+
     private validateRelationField(field: DataModelField, accept: ValidationAcceptor) {
         const thisRelation = this.parseRelation(field, accept);
         if (!thisRelation.valid) {
@@ -180,15 +212,20 @@ export default class DataModelValidator implements AstValidator<DataModel> {
             );
             return;
         } else if (oppositeFields.length > 1) {
-            oppositeFields.forEach((f) =>
-                accept(
-                    'error',
-                    `Fields ${oppositeFields.map((f) => '"' + f.name + '"').join(', ')} on model "${
-                        oppositeModel.name
-                    }" refer to the same relation to model "${field.$container.name}"`,
-                    { node: f }
-                )
-            );
+            oppositeFields.forEach((f) => {
+                if (this.isSelfRelation(f)) {
+                    // self relations are partial
+                    // https://www.prisma.io/docs/concepts/components/prisma-schema/relations/self-relations
+                } else {
+                    accept(
+                        'error',
+                        `Fields ${oppositeFields.map((f) => '"' + f.name + '"').join(', ')} on model "${
+                            oppositeModel.name
+                        }" refer to the same relation to model "${field.$container.name}"`,
+                        { node: f }
+                    );
+                }
+            });
             return;
         }
 

packages/schema/tests/schema/validation/datamodel-validation.test.ts

@@ -449,4 +449,80 @@ describe('Data Model Validation Tests', () => {
             }
         `);
     });
+
+    it('self relation', async () => {
+        // one-to-one
+        // https://www.prisma.io/docs/concepts/components/prisma-schema/relations/self-relations#one-to-one-self-relations
+        await loadModel(`
+            ${prelude}
+            model User {
+                id          Int     @id @default(autoincrement())
+                name        String?
+                successorId Int?    @unique
+                successor   User?   @relation("BlogOwnerHistory", fields: [successorId], references: [id])
+                predecessor User?   @relation("BlogOwnerHistory")
+            }
+        `);
+
+        // one-to-many
+        // https://www.prisma.io/docs/concepts/components/prisma-schema/relations/self-relations#one-to-many-self-relations
+        await loadModel(`
+            ${prelude}
+            model User {
+                id        Int     @id @default(autoincrement())
+                name      String?
+                teacherId Int?
+                teacher   User?   @relation("TeacherStudents", fields: [teacherId], references: [id])
+                students  User[]  @relation("TeacherStudents")
+            }
+        `);
+
+        // many-to-many
+        // https://www.prisma.io/docs/concepts/components/prisma-schema/relations/self-relations#many-to-many-self-relations
+        await loadModel(`
+            ${prelude}
+            model User {
+                id         Int     @id @default(autoincrement())
+                name       String?
+                followedBy User[]  @relation("UserFollows")
+                following  User[]  @relation("UserFollows")
+            }            
+        `);
+
+        // many-to-many explicit
+        // https://www.prisma.io/docs/concepts/components/prisma-schema/relations/self-relations#many-to-many-self-relations
+        await loadModel(`
+            ${prelude}
+            model User {
+                id         Int       @id @default(autoincrement())
+                name       String?
+                followedBy Follows[] @relation("following")
+                following  Follows[] @relation("follower")
+            }
+
+            model Follows {
+                follower    User @relation("follower", fields: [followerId], references: [id])
+                followerId  Int
+                following   User @relation("following", fields: [followingId], references: [id])
+                followingId Int
+
+                @@id([followerId, followingId])
+            }         
+        `);
+
+        // multiple self relations
+        // https://www.prisma.io/docs/concepts/components/prisma-schema/relations/self-relations#defining-multiple-self-relations-on-the-same-model
+        await loadModel(`
+            ${prelude}
+            model User {
+                id         Int     @id @default(autoincrement())
+                name       String?
+                teacherId  Int?
+                teacher    User?   @relation("TeacherStudents", fields: [teacherId], references: [id])
+                students   User[]  @relation("TeacherStudents")
+                followedBy User[]  @relation("UserFollows")
+                following  User[]  @relation("UserFollows")
+            }       
+        `);
+    });
 });

packages/sdk/package.json

@@ -1,6 +1,6 @@
 {
     "name": "@zenstackhq/sdk",
-    "version": "1.0.0-alpha.57",
+    "version": "1.0.0-alpha.58",
     "description": "ZenStack plugin development SDK",
     "main": "index.js",
     "scripts": {

packages/testtools/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@zenstackhq/testtools",
-  "version": "1.0.0-alpha.57",
+  "version": "1.0.0-alpha.58",
   "description": "ZenStack Test Tools",
   "main": "index.js",
   "publishConfig": {

tests/integration/tests/with-policy/relation-to-one-filter.test.ts

@@ -3,7 +3,6 @@ import path from 'path';
 
 describe('With Policy: relation to-one filter', () => {
     let origDir: string;
-    const suite = 'relation-to-one-filter';
 
     beforeAll(async () => {
         origDir = path.resolve('.');