fix: misc updates according to PR comments

apps/docs/src/app/documentation/core-helpers/sections-toolbar/sections-toolbar.component.html

@@ -29,8 +29,13 @@
                             <button fd-nested-list-expand-icon></button>
                         </div>
                         <ul fd-nested-list>
-                            <ng-container *ngFor="let item of section.content; trackBy: trackBySectionContent">
-                                <ng-container *ngIf="$any(item).subItems as itemSubItems; else rootListItem">
+                            <ng-container
+                                *ngFor="
+                                    let item of $asSectionNestedContent(section.content);
+                                    trackBy: trackBySectionContent
+                                "
+                            >
+                                <ng-container *ngIf="item.subItems as itemSubItems; else rootListItem">
                                     <li fd-nested-list-item [expanded]="true">
                                         <div fd-nested-list-content>
                                             <a fd-nested-list-link>

apps/docs/src/app/documentation/core-helpers/sections-toolbar/sections-toolbar.component.ts

@@ -30,7 +30,9 @@ export class SectionsToolbarComponent implements OnInit, OnChanges {
         return window.innerWidth < SMALL_SCREEN_BREAKPOINT;
     }
 
-    constructor() {}
+    /** @hidden type enforcing */
+    $asSectionNestedContent = (sectionContent: SectionInterfaceContent[]): SectionInterfaceContentNested[] =>
+        <any>sectionContent;
 
     ngOnInit(): void {
         this.onActivate();

apps/docs/src/app/platform/component-docs/platform-forms/checkbox/platform-checkbox-examples/platform-tristate-checkbox.component.ts

@@ -19,14 +19,12 @@ export class PlatformChekboxTristateComponent implements AfterViewInit {
     public cities = new FormGroup({});
     public citiesData = new SomeObject(false, 'Yes', null, false, true, null, null, false);
 
+    public agreementsFormGroup = new FormGroup({});
+
     public registrationForm = new FormGroup({
-        agreements: new FormGroup({})
+        agreements: this.agreementsFormGroup
     });
 
-    get agreementsFormGroup(): FormGroup {
-        return this.registrationForm.get('agreements') as FormGroup;
-    }
-
     public choices: Record<string, any> = { termsAndConditions: true, marketing: true, newsletter: false };
 
     // code for nested form group with tristate checkbox.

apps/docs/src/app/schema/pipes/type-casting.pipe.ts

@@ -1,16 +1,14 @@
 import { Pipe, PipeTransform } from '@angular/core';
 import { AbstractControl, FormControl, FormGroup } from '@angular/forms';
 
-@Pipe({ name: 'asFormGroup' })
-export class AsFormGroupPipe implements PipeTransform {
-    transform(value: AbstractControl): FormGroup {
-        return value as FormGroup;
+abstract class TypeEnforcerPipe<AsType, OriginalType = any> implements PipeTransform {
+    transform(value: OriginalType): AsType {
+        return (<any>value) as AsType;
     }
 }
 
+@Pipe({ name: 'asFormGroup' })
+export class AsFormGroupPipe extends TypeEnforcerPipe<FormGroup, AbstractControl> implements PipeTransform {}
+
 @Pipe({ name: 'asFormControl' })
-export class AsFormControlPipe implements PipeTransform {
-    transform(value: AbstractControl): FormControl {
-        return value as FormControl;
-    }
-}
+export class AsFormControlPipe extends TypeEnforcerPipe<FormControl, AbstractControl> implements PipeTransform {}

libs/platform/src/lib/form/checkbox-group/checkbox-group.component.ts

@@ -209,7 +209,7 @@ export class CheckboxGroupComponent extends InLineLayoutCollectionBaseInput {
 
     /** @hidden */
     public getListItemDisabledValue(item: CheckboxGroupComponent['list'][number]): boolean {
-        return this.disabled || (typeof item === 'object' && !!(<SelectItem>item).disabled);
+        return this.disabled || !!(<SelectItem>item)?.disabled;
     }
 
     /** @hidden */