feat(@angular-devkit/core): add a new JsonSchema type

A Schema is either an Object or a boolean. We could reduce JsonSchema scope further
by adding properties, but a schema is a really complex type so its not worth the
effort.

Author: hansl

etc/api/angular_devkit/core/src/_golden-api.d.ts

@@ -165,7 +165,7 @@ export declare class CoreSchemaRegistry implements SchemaRegistry {
     addPostTransform(visitor: JsonVisitor, deps?: JsonVisitor[]): void;
     addPreTransform(visitor: JsonVisitor, deps?: JsonVisitor[]): void;
     addSmartDefaultProvider<T>(source: string, provider: SmartDefaultProvider<T>): void;
-    compile(schema: JsonObject): Observable<SchemaValidator>;
+    compile(schema: JsonSchema): Observable<SchemaValidator>;
     flatten(schema: JsonObject): Observable<JsonObject>;
     registerUriHandler(handler: UriHandler): void;
     usePromptProvider(provider: PromptProvider): void;
@@ -226,7 +226,7 @@ export declare function fragment(path: string): PathFragment;
 
 export declare function getSystemPath(path: Path): string;
 
-export declare function getTypesOfSchema(schema: JsonObject | true): Set<string>;
+export declare function getTypesOfSchema(schema: JsonSchema): Set<string>;
 
 export declare const gray: (x: string) => string;
 
@@ -991,7 +991,7 @@ export declare type UriHandler = (uri: string) => Observable<JsonObject> | Promi
 
 export declare function visitJson<ContextT>(json: JsonValue, visitor: JsonVisitor, schema?: JsonObject, refResolver?: ReferenceResolver<ContextT>, context?: ContextT): Observable<JsonValue>;
 
-export declare function visitJsonSchema(schema: JsonObject, visitor: JsonSchemaVisitor): void;
+export declare function visitJsonSchema(schema: JsonSchema, visitor: JsonSchemaVisitor): void;
 
 export declare const white: (x: string) => string;
 

packages/angular/cli/utilities/json-schema.ts

@@ -36,7 +36,9 @@ function _getEnumFromValue<E, T extends E[keyof E]>(
   }
 
   if (Object.values(enumeration).indexOf(value) !== -1) {
-    return value as unknown as T;
+    // TODO: this should be unknown
+    // tslint:disable-next-line:no-any
+    return value as any as T;
   }
 
   return defaultValue;

packages/angular_devkit/core/src/json/schema/index.ts

@@ -8,6 +8,7 @@
 export * from './interface';
 export * from './pointer';
 export * from './registry';
+export * from './schema';
 export * from './visitor';
 export * from './utility';
 

packages/angular_devkit/core/src/json/schema/registry.ts

@@ -27,6 +27,7 @@ import {
   SchemaValidatorResult,
   SmartDefaultProvider,
 } from './interface';
+import { JsonSchema } from './schema';
 import { visitJson, visitJsonSchema } from './visitor';
 
 // This interface should be exported from ajv, but they only export the class and not the type.
@@ -299,7 +300,7 @@ export class CoreSchemaRegistry implements SchemaRegistry {
    * (using schema as a URI).
    * @returns An Observable of the Validation function.
    */
-  compile(schema: JsonObject): Observable<SchemaValidator> {
+  compile(schema: JsonSchema): Observable<SchemaValidator> {
     const schemaInfo: SchemaInfo = {
       smartDefaultRecord: new Map<string, JsonObject>(),
       promptDefinitions: [],
@@ -346,6 +347,10 @@ export class CoreSchemaRegistry implements SchemaRegistry {
             // tslint:disable-next-line:no-any https://github.com/ReactiveX/rxjs/issues/3989
             result = (result as any).pipe(
               ...[...this._pre].map(visitor => concatMap((data: JsonValue) => {
+                if (schema === false || schema === true) {
+                  return of(data);
+                }
+
                 return visitJson(data, visitor, schema, this._resolver, validate);
               })),
             );
@@ -368,6 +373,9 @@ export class CoreSchemaRegistry implements SchemaRegistry {
 
                 return value;
               };
+              if (schema === false || schema === true) {
+                return of(updatedData);
+              }
 
               return visitJson(updatedData, visitor, schema, this._resolver, validate);
             }),
@@ -410,6 +418,10 @@ export class CoreSchemaRegistry implements SchemaRegistry {
                   // tslint:disable-next-line:no-any https://github.com/ReactiveX/rxjs/issues/3989
                   result = (result as any).pipe(
                     ...[...this._post].map(visitor => concatMap((data: JsonValue) => {
+                      if (schema === false || schema === true) {
+                        return of(schema);
+                      }
+
                       return visitJson(data, visitor, schema, this._resolver, validate);
                     })),
                   );

packages/angular_devkit/core/src/json/schema/schema.ts

@@ -0,0 +1,15 @@
+/**
+ * @license
+ * Copyright Google Inc. All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.io/license
+ */
+import { JsonObject } from '../interface';
+
+/**
+ * A specialized interface for JsonSchema (to come). JsonSchemas are also JsonObject.
+ *
+ * @public
+ */
+export type JsonSchema = JsonObject | boolean;

packages/angular_devkit/core/src/json/schema/utility.ts

@@ -6,11 +6,12 @@
  * found in the LICENSE file at https://angular.io/license
  */
 import { JsonObject, isJsonArray, isJsonObject } from '../interface';
+import { JsonSchema } from './schema';
 
 
 const allTypes = ['string', 'integer', 'number', 'object', 'array', 'boolean', 'null'];
 
-export function getTypesOfSchema(schema: JsonObject | true): Set<string> {
+export function getTypesOfSchema(schema: JsonSchema): Set<string> {
   if (!schema) {
     return new Set();
   }

packages/angular_devkit/core/src/json/schema/visitor.ts

@@ -11,6 +11,7 @@ import { isObservable } from '../../utils';
 import { JsonArray, JsonObject, JsonValue } from '../interface';
 import { JsonPointer, JsonSchemaVisitor, JsonVisitor } from './interface';
 import { buildJsonPointer, joinJsonPointer } from './pointer';
+import { JsonSchema } from './schema';
 
 
 export interface ReferenceResolver<ContextT> {
@@ -139,7 +140,12 @@ export function visitJson<ContextT>(
 }
 
 
-export function visitJsonSchema(schema: JsonObject, visitor: JsonSchemaVisitor) {
+export function visitJsonSchema(schema: JsonSchema, visitor: JsonSchemaVisitor) {
+  if (schema === false || schema === true) {
+    // Nothing to visit.
+    return;
+  }
+
   const keywords = {
     additionalItems: true,
     items: true,