feat(ValidationErrors): add feature to store errors of the `Validatio…

…nError` type and throw on demand.

src/lib/validation-errors.class.ts

@@ -0,0 +1,53 @@
+import { CommonErrors } from './common-errors.class';
+import { ValidationError } from './validation-error.class';
+/**
+ * The `ValidationErrors` is an extension of the `CommonErrors` object that represents multiple identification numbers under which the
+ * errors of the `ValidationError` type are prepared to throw.
+ */
+export class ValidationErrors<Id extends string> extends CommonErrors<Id> {
+  //#region constructor.
+  /**
+   * Creates the `ValidationErrors` instance of unique identification numbers under which the `ValidationError` objects are stored.
+   * @param id A rest parameter of generic type variable `Id` indicates unique identification numbers under which the `ValidationError`
+   * objects are stored.
+   * @angularpackage
+   */
+  constructor(...id: Id[]) {
+    super(...id);
+  }
+  //#endregion constructor.
+
+  //#region instance public methods.
+  /**
+   * Sets the `ValidationError` object with the message built from the given required `problem`, `fix`, `id` on the given or stored
+   * `template` under the given `id`.
+   * @param problem Description of the problem of a `string` type.
+   * @param fix A solution to the given `problem` of a string type.
+   * @param id The unique identification to the given `problem` of generic type variable `ErrorId`.
+   * @param template A template of error message with the replaceable `{problem}`, `{fix}`, `{id}` tags. By default, the value is equal
+   * to the static property `ValidationErrors.template`.
+   * @returns The return value is an instance of `Errors`.
+   * @angularpackage
+   */
+  public set<ErrorId extends Id>(
+    problem: string,
+    fix: string,
+    id: ErrorId,
+    template = ValidationErrors.template
+  ): this {
+    this.isAllowedId(id) &&
+      this.errors.set(id, new ValidationError(problem, fix, id, template));
+    return this;
+  }
+
+  /**
+   * The method returns the JSON object of set errors, where the key is a unique identification.
+   * @returns The return value is an `object` of set errors.
+   * @angularpackage
+   */
+  public toObject(): { [Key in Id]: ValidationError<Id> } {
+    return Object.fromEntries(this.errors.entries()) as any;
+  }
+
+  //#endregion instance public methods.
+}