Merge the reworked Form Validator into the fork's integration line

Brings feat/form-validator-bridge-v2 (the eclipsesource#2644 rework on current
upstream master) into fork master and ports the stacked work to the new
API:

- core: `state.validator` holds the Form Validator, the custom factory
  is kept in `state.validatorFactory`; no default Ajv instance is
  created while a factory is set (eclipsesource#2648).
- rules (eclipsesource#2645): conditions are evaluated with the validator factory
  (one cached Form Validator per condition schema) or the Ajv instance;
  `matches` and the bound-validator branch are gone. `getRuleValidator`
  reads `validatorFactory ?? ajv`.
- bindings (eclipsesource#2646): the `validator` prop of React, Vue and Angular is a
  FormValidatorFactory; `useValidator` reads `state.validator`.
- standard-schema: `fromStandardSchema` returns a factory. For its own
  JSON Schema it validates with the library and sets `parentSchema` per
  issue (`schemaAt`, moved here from core); for other schemas, e.g. rule
  conditions, it uses core's schema matcher. No `severity`.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01B36yeVG6EUUhwMCEzybGEH

Author: gigibiffi84

MIGRATION.md

@@ -2,6 +2,25 @@
 
 ## Migration to JSON Forms 3.9
 
+### `validator` in the core state is a Form Validator
+
+JSON Forms 3.9 adds a `validator` option to plug in a custom validation library. It takes a factory `(schema) => FormValidator` and takes precedence over `ajv`. Without it, Ajv validates as before.
+
+As a consequence, `JsonFormsCore.validator` now holds a `FormValidator` instead of the compiled Ajv `ValidateFunction`.
+If you read `state.validator` or build the core state by hand, call `validator.validate(data)`, which returns `ValidationIssue`s, or wrap a compiled Ajv function with `compiledAjvValidator(validateFn)`.
+
+### JSON Schema generation supports non-object root values
+
+`generateJsonSchema` now generates a schema matching the root value's actual type. In particular, arrays produce an array schema with an `items` schema, primitives produce their corresponding primitive schema, and `undefined` produces an empty schema.
+
+Previously all root values were handled as objects. For example, `generateJsonSchema([1, 2])` produced an object schema with properties named `"0"` and `"1"`; it now produces an array schema with an integer `items` schema. If you depend on the previous object-shaped output, adapt the generated schema before consuming it.
+
+### Default UI schema generation always returns a layout
+
+`generateDefaultUISchema` previously returned `null` when no UI schema elements could be generated. It now returns an empty layout of the requested type instead.
+
+If you call `generateDefaultUISchema` directly, remove any `null` handling and check the returned layout's `elements` when you need to know whether controls were generated.
+
 ### Data update paths treat all segments literally
 
 Data updates (e.g. dispatched `update` actions) previously wrote to the form data via lodash's `set`/`unset`, which interpret bracket notation and array indices in paths.

package.json

@@ -21,8 +21,7 @@
     "build:examples-app": "lerna run build:examples-app && node packages/examples-app/prepare-examples-app.js"
   },
   "devDependencies": {
-    "@babel/plugin-proposal-nullish-coalescing-operator": "^7.16.5",
-    "@babel/plugin-proposal-optional-chaining": "^7.16.5",
+    "@babel/preset-env": "^7.29.7",
     "@istanbuljs/nyc-config-typescript": "^1.0.2",
     "@types/lodash": "^4.14.149",
     "ajv": "^8.18.0",

packages/angular-material/package.json

@@ -78,7 +78,7 @@
     "rxjs": "^6.6.0 || ^7.4.0"
   },
   "dependencies": {
-    "lodash": "^4.17.21"
+    "lodash": "^4.18.1"
   },
   "devDependencies": {
     "@angular-devkit/build-angular": "^20.0.0",
@@ -87,20 +87,18 @@
     "@angular-eslint/eslint-plugin-template": "^20.7.0",
     "@angular-eslint/schematics": "^20.7.0",
     "@angular-eslint/template-parser": "^20.7.0",
-    "@angular/animations": "^20.3.24",
+    "@angular/animations": "^20.3.33",
     "@angular/cdk": "^20.2.14",
-    "@angular/cli": "^20.3.27",
-    "@angular/common": "^20.3.24",
-    "@angular/compiler": "^20.3.24",
-    "@angular/compiler-cli": "^20.3.24",
-    "@angular/core": "^20.3.24",
-    "@angular/forms": "^20.3.24",
+    "@angular/cli": "^20.3.38",
+    "@angular/common": "^20.3.33",
+    "@angular/compiler": "^20.3.33",
+    "@angular/compiler-cli": "^20.3.33",
+    "@angular/core": "^20.3.33",
+    "@angular/forms": "^20.3.33",
     "@angular/material": "^20.2.14",
-    "@angular/platform-browser": "^20.3.24",
-    "@angular/platform-browser-dynamic": "^20.3.24",
-    "@angular/router": "^20.3.24",
-    "@babel/plugin-proposal-nullish-coalescing-operator": "^7.16.5",
-    "@babel/plugin-proposal-optional-chaining": "^7.16.5",
+    "@angular/platform-browser": "^20.3.33",
+    "@angular/platform-browser-dynamic": "^20.3.33",
+    "@angular/router": "^20.3.33",
     "@jsonforms/angular": "workspace:*",
     "@jsonforms/core": "workspace:*",
     "@jsonforms/examples": "workspace:*",
@@ -110,9 +108,8 @@
     "@types/node": "^24.12.2",
     "@typescript-eslint/eslint-plugin": "^5.54.1",
     "@typescript-eslint/parser": "^5.54.1",
-    "babel-loader": "^8.0.6",
     "copy-webpack-plugin": "^11.0.0",
-    "dayjs": "^1.11.10",
+    "dayjs": "^1.11.11",
     "eslint": "^8.56.0",
     "eslint-config-prettier": "^8.7.0",
     "eslint-plugin-import": "^2.27.5",
@@ -134,7 +131,7 @@
     "prettier": "^2.8.4",
     "protractor": "^7.0.0",
     "rimraf": "^6.1.0",
-    "rxjs": "^6.6.0",
+    "rxjs": "^6.6.7",
     "ts-loader": "^9.5.1",
     "tslib": "^2.5.0",
     "typedoc": "~0.25.3",

packages/angular/package.json

@@ -68,7 +68,7 @@
     ]
   },
   "dependencies": {
-    "lodash": "^4.17.21"
+    "lodash": "^4.18.1"
   },
   "peerDependencies": {
     "@angular/core": "^20.0.0 || ^21.0.0 || ^22.0.0",
@@ -81,10 +81,10 @@
     "@angular-eslint/eslint-plugin-template": "^20.7.0",
     "@angular-eslint/schematics": "^20.7.0",
     "@angular-eslint/template-parser": "^20.7.0",
-    "@angular/compiler": "^20.3.24",
-    "@angular/compiler-cli": "^20.3.24",
-    "@angular/core": "^20.3.24",
-    "@angular/forms": "^20.3.24",
+    "@angular/compiler": "^20.3.33",
+    "@angular/compiler-cli": "^20.3.33",
+    "@angular/core": "^20.3.33",
+    "@angular/forms": "^20.3.33",
     "@jsonforms/core": "workspace:*",
     "@typescript-eslint/eslint-plugin": "^5.54.1",
     "@typescript-eslint/parser": "^5.54.1",
@@ -98,7 +98,7 @@
     "nyc": "^15.1.0",
     "prettier": "^2.8.4",
     "rimraf": "^6.1.0",
-    "rxjs": "^6.6.0",
+    "rxjs": "^6.6.7",
     "source-map-support": "^0.5.21",
     "tslib": "^2.3.0",
     "typedoc": "~0.25.3",

packages/angular/src/library/jsonforms-root.component.ts

@@ -44,7 +44,7 @@ import {
   UISchemaElement,
   UISchemaTester,
   ValidationMode,
-  ValidatorOption,
+  FormValidatorFactory,
 } from '@jsonforms/core';
 import type Ajv from 'ajv';
 import type { ErrorObject } from 'ajv';
@@ -72,7 +72,7 @@ export class JsonForms implements DoCheck, OnChanges, OnInit, OnDestroy {
   @Input() readonly: boolean;
   @Input() validationMode: ValidationMode;
   @Input() ajv: Ajv;
-  @Input() validator: ValidatorOption;
+  @Input() validator: FormValidatorFactory;
   @Input() config: JsonFormsAngularConfig;
   @Input() i18n: JsonFormsI18nState;
   @Input() additionalErrors: ErrorObject[];
@@ -97,7 +97,7 @@ export class JsonForms implements DoCheck, OnChanges, OnInit, OnDestroy {
           uischema: this.uischema,
           schema: this.schema,
           ajv: this.ajv,
-          validatorOption: this.validator,
+          validatorFactory: this.validator,
           validationMode: this.validationMode,
           additionalErrors: this.additionalErrors,
         },

packages/angular/src/library/jsonforms.service.ts

@@ -46,7 +46,7 @@ import {
   updateI18n,
   Middleware,
   defaultMiddleware,
-  ValidatorOption,
+  FormValidatorFactory,
 } from '@jsonforms/core';
 import { BehaviorSubject, Observable } from 'rxjs';
 import type { JsonFormsBaseRenderer } from './base.renderer';
@@ -295,7 +295,7 @@ export class JsonFormsAngularService {
     ajv: Ajv | typeof USE_STATE_VALUE,
     validationMode: ValidationMode | typeof USE_STATE_VALUE,
     additionalErrors: ErrorObject[] | typeof USE_STATE_VALUE,
-    validator: ValidatorOption | typeof USE_STATE_VALUE = USE_STATE_VALUE
+    validator: FormValidatorFactory | typeof USE_STATE_VALUE = USE_STATE_VALUE
   ): void {
     const newData = data === USE_STATE_VALUE ? this._state.core.data : data;
     const newSchema =
@@ -317,7 +317,7 @@ export class JsonFormsAngularService {
         : additionalErrors;
     const newValidator =
       validator === USE_STATE_VALUE
-        ? this._state.core.validatorOption
+        ? this._state.core.validatorFactory
         : validator;
     this.updateCore(
       Actions.updateCore(newData, newSchema, newUischema, {

packages/core/package.json

@@ -68,10 +68,10 @@
     ]
   },
   "dependencies": {
-    "@types/json-schema": "^7.0.3",
+    "@types/json-schema": "^7.0.15",
     "ajv": "^8.18.0",
-    "ajv-formats": "^2.1.0",
-    "lodash": "^4.17.21"
+    "ajv-formats": "^2.1.1",
+    "lodash": "^4.18.1"
   },
   "devDependencies": {
     "@istanbuljs/nyc-config-typescript": "^1.0.2",

packages/core/src/actions/actions.ts

@@ -25,7 +25,7 @@
 
 import type AJV from 'ajv';
 import type { ErrorObject } from 'ajv';
-import type { ValidatorOption } from '../util/formValidator';
+import type { FormValidatorFactory } from '../util/formValidator';
 import { JsonSchema, UISchemaElement } from '../models';
 import { generateDefaultUISchema, generateJsonSchema } from '../generators';
 
@@ -146,15 +146,9 @@ export interface UpdateCoreAction {
 }
 
 export interface InitActionOptions {
-  /** The AJV instance to validate with. Ignored for form validation when `validator` is set. */
   ajv?: AJV;
-  /**
-   * A custom Form Validator: a factory producing one per schema, or a
-   * validator already bound to the schema. Takes precedence over `ajv`.
-   * Passing `undefined` explicitly switches back to AJV; leaving the key out
-   * keeps the validator currently in use.
-   */
-  validator?: ValidatorOption;
+  /** Creates the Form Validator for the schema. Takes precedence over `ajv`. */
+  validator?: FormValidatorFactory;
   validationMode?: ValidationMode;
   additionalErrors?: ErrorObject[];
 }

packages/core/src/generators/Generate.ts

@@ -28,9 +28,7 @@ import { generateJsonSchema } from './schema';
 import { createControlElement, generateDefaultUISchema } from './uischema';
 
 export const Generate: {
-  // TODO fix @typescript-eslint/ban-types
-  // eslint-disable-next-line @typescript-eslint/ban-types
-  jsonSchema(instance: Object, options?: any): JsonSchema;
+  jsonSchema(instance: unknown, options?: any): JsonSchema;
   uiSchema(
     jsonSchema: JsonSchema,
     layoutType?: string,

packages/core/src/generators/schema.ts

@@ -52,9 +52,7 @@ class Gen {
     private findOption: (props: Properties) => (optionName: string) => any
   ) {}
 
-  // TODO fix @typescript-eslint/ban-types
-  // eslint-disable-next-line @typescript-eslint/ban-types
-  schemaObject = (data: Object): JsonSchema4 => {
+  schemaObject = (data: Record<string, any>): JsonSchema4 => {
     const props: Properties = this.properties(data);
     const schema: JsonSchema4 = {
       type: 'object',
@@ -140,14 +138,12 @@ class Gen {
 
 /**
  * Generate a JSON schema based on the given data and any additional options.
- * @param {Object} instance the data to create a JSON schema for
+ * @param {unknown} instance the data to create a JSON schema for
  * @param {any} options any additional options that may alter the generated JSON schema
  * @returns {JsonSchema} the generated schema
  */
 export const generateJsonSchema = (
-  // TODO fix @typescript-eslint/ban-types
-  // eslint-disable-next-line @typescript-eslint/ban-types
-  instance: Object,
+  instance: unknown,
   options: any = {}
 ): JsonSchema4 => {
   const findOption =
@@ -177,5 +173,5 @@ export const generateJsonSchema = (
 
   const gen = new Gen(findOption);
 
-  return gen.schemaObject(instance);
+  return gen.property(instance);
 };