fix(material/datepicker): simplify DI setup

Previously we had to define an injection token for the `MatDateRangeInput` in order to avoid circular references. Now we can do the same with a type-only imports so we can simplify the setup.

Fixes #30238.

src/material/datepicker/date-range-input-parts.ts

@@ -8,17 +8,7 @@
 
 import {Directionality} from '@angular/cdk/bidi';
 import {BACKSPACE, LEFT_ARROW, RIGHT_ARROW} from '@angular/cdk/keycodes';
-import {
-  Directive,
-  DoCheck,
-  ElementRef,
-  InjectionToken,
-  Injector,
-  Input,
-  OnInit,
-  Signal,
-  inject,
-} from '@angular/core';
+import {Directive, DoCheck, ElementRef, Injector, Input, OnInit, inject} from '@angular/core';
 import {
   AbstractControl,
   FormGroupDirective,
@@ -33,34 +23,8 @@ import {
 import {ErrorStateMatcher, _ErrorStateTracker} from '@angular/material/core';
 import {_computeAriaAccessibleName} from './aria-accessible-name';
 import {DateRange, DateSelectionModelChange} from './date-selection-model';
-import {DateFilterFn, MatDatepickerInputBase} from './datepicker-input-base';
-
-/** Parent component that should be wrapped around `MatStartDate` and `MatEndDate`. */
-export interface MatDateRangeInputParent<D> {
-  id: string;
-  min: D | null;
-  max: D | null;
-  dateFilter: DateFilterFn<D>;
-  rangePicker: {
-    opened: boolean;
-    id: string;
-  };
-  // @breaking-change 20.0.0 property to become required.
-  _ariaOwns?: Signal<string | null>;
-  _startInput: MatDateRangeInputPartBase<D>;
-  _endInput: MatDateRangeInputPartBase<D>;
-  _groupDisabled: boolean;
-  _handleChildValueChange(): void;
-  _openDatepicker(): void;
-}
-
-/**
- * Used to provide the date range input wrapper component
- * to the parts without circular dependencies.
- */
-export const MAT_DATE_RANGE_INPUT_PARENT = new InjectionToken<MatDateRangeInputParent<unknown>>(
-  'MAT_DATE_RANGE_INPUT_PARENT',
-);
+import {MatDatepickerInputBase} from './datepicker-input-base';
+import {MatDateRangeInput} from './date-range-input';
 
 /**
  * Base class for the individual inputs that can be projected inside a `mat-date-range-input`.
@@ -70,7 +34,7 @@ abstract class MatDateRangeInputPartBase<D>
   extends MatDatepickerInputBase<DateRange<D>>
   implements OnInit, DoCheck
 {
-  _rangeInput = inject<MatDateRangeInputParent<D>>(MAT_DATE_RANGE_INPUT_PARENT);
+  _rangeInput = inject<MatDateRangeInput<D>>(MatDateRangeInput);
   override _elementRef = inject<ElementRef<HTMLInputElement>>(ElementRef);
   _defaultErrorStateMatcher = inject(ErrorStateMatcher);
   private _injector = inject(Injector);
@@ -86,6 +50,7 @@ abstract class MatDateRangeInputPartBase<D>
   protected abstract override _validator: ValidatorFn | null;
   protected abstract override _assignValueToModel(value: D | null): void;
   protected abstract override _getValueFromModel(modelValue: DateRange<D>): D | null;
+  protected abstract _register(): void;
   protected readonly _dir = inject(Directionality, {optional: true});
   private _errorStateTracker: _ErrorStateTracker;
 
@@ -133,6 +98,8 @@ abstract class MatDateRangeInputPartBase<D>
       this.ngControl = ngControl;
       this._errorStateTracker.ngControl = ngControl;
     }
+
+    this._register();
   }
 
   ngDoCheck() {
@@ -208,7 +175,7 @@ abstract class MatDateRangeInputPartBase<D>
   protected override _assignValueProgrammatically(value: D | null) {
     super._assignValueProgrammatically(value);
     const opposite = (
-      this === this._rangeInput._startInput
+      this === (this._rangeInput._startInput as MatDateRangeInputPartBase<D>)
         ? this._rangeInput._endInput
         : this._rangeInput._startInput
     ) as MatDateRangeInputPartBase<D> | undefined;
@@ -261,6 +228,10 @@ export class MatStartDate<D> extends MatDateRangeInputPartBase<D> {
 
   protected _validator = Validators.compose([...super._getValidators(), this._startValidator]);
 
+  protected override _register(): void {
+    this._rangeInput._startInput = this;
+  }
+
   protected _getValueFromModel(modelValue: DateRange<D>) {
     return modelValue.start;
   }
@@ -349,6 +320,10 @@ export class MatEndDate<D> extends MatDateRangeInputPartBase<D> {
       : {'matEndDateInvalid': {'start': start, 'actual': end}};
   };
 
+  protected override _register(): void {
+    this._rangeInput._endInput = this;
+  }
+
   protected _validator = Validators.compose([...super._getValidators(), this._endValidator]);
 
   protected _getValueFromModel(modelValue: DateRange<D>) {

src/material/datepicker/date-range-input.ts

@@ -12,7 +12,6 @@ import {
   ChangeDetectionStrategy,
   ChangeDetectorRef,
   Component,
-  ContentChild,
   ElementRef,
   Input,
   OnChanges,
@@ -27,12 +26,7 @@ import {ControlContainer, NgControl, Validators} from '@angular/forms';
 import {DateAdapter, ThemePalette} from '@angular/material/core';
 import {MAT_FORM_FIELD, MatFormFieldControl} from '@angular/material/form-field';
 import {Subject, Subscription, merge} from 'rxjs';
-import {
-  MAT_DATE_RANGE_INPUT_PARENT,
-  MatDateRangeInputParent,
-  MatEndDate,
-  MatStartDate,
-} from './date-range-input-parts';
+import type {MatEndDate, MatStartDate} from './date-range-input-parts';
 import {MatDateRangePickerInput} from './date-range-picker';
 import {DateRange, MatDateSelectionModel} from './date-selection-model';
 import {MatDatepickerControl, MatDatepickerPanel} from './datepicker-base';
@@ -58,17 +52,13 @@ import {DateFilterFn, _MatFormFieldPartial, dateInputsHaveChanged} from './datep
   },
   changeDetection: ChangeDetectionStrategy.OnPush,
   encapsulation: ViewEncapsulation.None,
-  providers: [
-    {provide: MatFormFieldControl, useExisting: MatDateRangeInput},
-    {provide: MAT_DATE_RANGE_INPUT_PARENT, useExisting: MatDateRangeInput},
-  ],
+  providers: [{provide: MatFormFieldControl, useExisting: MatDateRangeInput}],
   imports: [CdkMonitorFocus],
 })
 export class MatDateRangeInput<D>
   implements
     MatFormFieldControl<DateRange<D>>,
     MatDatepickerControl<D>,
-    MatDateRangeInputParent<D>,
     MatDateRangePickerInput<D>,
     AfterContentInit,
     OnChanges,
@@ -82,6 +72,9 @@ export class MatDateRangeInput<D>
   private _closedSubscription = Subscription.EMPTY;
   private _openedSubscription = Subscription.EMPTY;
 
+  _startInput: MatStartDate<D>;
+  _endInput: MatEndDate<D>;
+
   /** Current value of the range input. */
   get value() {
     return this._model ? this._model.selection : null;
@@ -254,9 +247,6 @@ export class MatDateRangeInput<D>
   /** End of the comparison range that should be shown in the calendar. */
   @Input() comparisonEnd: D | null = null;
 
-  @ContentChild(MatStartDate) _startInput: MatStartDate<D>;
-  @ContentChild(MatEndDate) _endInput: MatEndDate<D>;
-
   /**
    * Implemented as a part of `MatFormFieldControl`.
    * TODO(crisbeto): change type to `AbstractControlDirective` after #18206 lands.

tools/public_api_guard/material/datepicker.md

@@ -41,7 +41,6 @@ import { OnInit } from '@angular/core';
 import { Overlay } from '@angular/cdk/overlay';
 import { Portal } from '@angular/cdk/portal';
 import { ScrollStrategy } from '@angular/cdk/overlay';
-import { Signal } from '@angular/core';
 import { SimpleChanges } from '@angular/core';
 import { Subject } from 'rxjs';
 import { TemplatePortal } from '@angular/cdk/portal';
@@ -568,7 +567,7 @@ export class MatDatepickerToggleIcon {
 }
 
 // @public (undocumented)
-export class MatDateRangeInput<D> implements MatFormFieldControl<DateRange<D>>, MatDatepickerControl<D>, MatDateRangeInputParent<D>, MatDateRangePickerInput<D>, AfterContentInit, OnChanges, OnDestroy {
+export class MatDateRangeInput<D> implements MatFormFieldControl<DateRange<D>>, MatDatepickerControl<D>, MatDateRangePickerInput<D>, AfterContentInit, OnChanges, OnDestroy {
     constructor(...args: unknown[]);
     _ariaDescribedBy: string | null;
     _ariaOwns: WritableSignal<string | null>;
@@ -632,7 +631,7 @@ export class MatDateRangeInput<D> implements MatFormFieldControl<DateRange<D>>,
     _updateFocus(origin: FocusOrigin): void;
     get value(): DateRange<D> | null;
     // (undocumented)
-    static ɵcmp: i0.ɵɵComponentDeclaration<MatDateRangeInput<any>, "mat-date-range-input", ["matDateRangeInput"], { "rangePicker": { "alias": "rangePicker"; "required": false; }; "required": { "alias": "required"; "required": false; }; "dateFilter": { "alias": "dateFilter"; "required": false; }; "min": { "alias": "min"; "required": false; }; "max": { "alias": "max"; "required": false; }; "disabled": { "alias": "disabled"; "required": false; }; "separator": { "alias": "separator"; "required": false; }; "comparisonStart": { "alias": "comparisonStart"; "required": false; }; "comparisonEnd": { "alias": "comparisonEnd"; "required": false; }; }, {}, ["_startInput", "_endInput"], ["input[matStartDate]", "input[matEndDate]"], true, never>;
+    static ɵcmp: i0.ɵɵComponentDeclaration<MatDateRangeInput<any>, "mat-date-range-input", ["matDateRangeInput"], { "rangePicker": { "alias": "rangePicker"; "required": false; }; "required": { "alias": "required"; "required": false; }; "dateFilter": { "alias": "dateFilter"; "required": false; }; "min": { "alias": "min"; "required": false; }; "max": { "alias": "max"; "required": false; }; "disabled": { "alias": "disabled"; "required": false; }; "separator": { "alias": "separator"; "required": false; }; "comparisonStart": { "alias": "comparisonStart"; "required": false; }; "comparisonEnd": { "alias": "comparisonEnd"; "required": false; }; }, {}, never, ["input[matStartDate]", "input[matEndDate]"], true, never>;
     // (undocumented)
     static ɵfac: i0.ɵɵFactoryDeclaration<MatDateRangeInput<any>, never>;
 }
@@ -686,6 +685,8 @@ export class MatEndDate<D> extends MatDateRangeInputPartBase<D> {
     // (undocumented)
     _onKeydown(event: KeyboardEvent): void;
     // (undocumented)
+    protected _register(): void;
+    // (undocumented)
     protected _shouldHandleChangeEvent(change: DateSelectionModelChange<DateRange<D>>): boolean;
     // (undocumented)
     protected _validator: ValidatorFn | null;
@@ -838,6 +839,8 @@ export class MatStartDate<D> extends MatDateRangeInputPartBase<D> {
     // (undocumented)
     _onKeydown(event: KeyboardEvent): void;
     // (undocumented)
+    protected _register(): void;
+    // (undocumented)
     protected _shouldHandleChangeEvent(change: DateSelectionModelChange<DateRange<D>>): boolean;
     // (undocumented)
     protected _validator: ValidatorFn | null;