Use new eslint-plugin-functional instead of tslint-immutable

src/file/xml-components/default-attributes.ts

@@ -1,11 +1,11 @@
 import { BaseXmlComponent, IContext } from "./base";
 import { IXmlableObject } from "./xmlable-object";
 
-export type AttributeMap<T> = { [P in keyof T]: string };
+export type AttributeMap<T> = { readonly [P in keyof T]: string };
 
-export abstract class XmlAttributeComponent<T> extends BaseXmlComponent {
+export abstract class XmlAttributeComponent<T extends object> extends BaseXmlComponent {
     // tslint:disable-next-line:readonly-keyword
-    protected root: T;
+    protected readonly root: T;
     protected readonly xmlKeys?: AttributeMap<T>;
 
     public constructor(properties: T) {
@@ -19,6 +19,7 @@ export abstract class XmlAttributeComponent<T> extends BaseXmlComponent {
             const value = this.root[key];
             if (value !== undefined) {
                 const newKey = (this.xmlKeys && this.xmlKeys[key]) || key;
+                // eslint-disable-next-line functional/immutable-data
                 attrs[newKey] = value;
             }
         });

src/file/xml-components/imported-xml-component.ts

@@ -1,4 +1,4 @@
-// tslint:disable:no-any
+// eslint-disable @typescript-eslint/no-explicit-any
 import { Element as XmlElement, xml2js } from "xml-js";
 
 import { IXmlableObject, XmlAttributeComponent, XmlComponent } from "@file/xml-components";
@@ -7,6 +7,7 @@ import { IContext } from "./base";
 
 /**
  * Converts the given xml element (in json format) into XmlComponent.
+ *
  * @param element the xml element in json presentation
  */
 

src/file/xml-components/xml-component.ts

@@ -4,7 +4,7 @@ import { IXmlableObject } from "./xmlable-object";
 export const EMPTY_OBJECT = Object.seal({});
 
 export abstract class XmlComponent extends BaseXmlComponent {
-    // tslint:disable-next-line:readonly-keyword no-any
+    // eslint-disable-next-line functional/prefer-readonly-type, @typescript-eslint/no-explicit-any
     protected root: (BaseXmlComponent | string | any)[];
 
     public constructor(rootKey: string) {
@@ -46,5 +46,7 @@ export abstract class IgnoreIfEmptyXmlComponent extends XmlComponent {
         if (result && (typeof result[this.rootKey] !== "object" || Object.keys(result[this.rootKey]).length)) {
             return result;
         }
+
+        return undefined;
     }
 }