refactor(forms): tree-shake _checkParentType in production (#60041)

In this commit, we move `_checkParentType` to a separate function to avoid a redundant prototype method in production.

PR Close #60041

packages/core/test/bundling/forms_reactive/bundle.golden_symbols.json

@@ -222,7 +222,6 @@
   "_bind",
   "_currentInjector",
   "_global",
-  "_hasInvalidParent",
   "_injectImplementation",
   "_isRefreshingViews",
   "_keyMap",
@@ -411,6 +410,7 @@
   "handleUnhandledError",
   "hasApplyArgsData",
   "hasInSkipHydrationBlockFlag",
+  "hasInvalidParent",
   "hasParentInjector",
   "hasTagAndTypeMatch",
   "hasValidator",

packages/forms/src/directives/ng_model.ts

@@ -334,24 +334,11 @@ export class NgModel extends NgControl implements OnChanges, OnDestroy {
 
   private _checkForErrors(): void {
     if ((typeof ngDevMode === 'undefined' || ngDevMode) && !this._isStandalone()) {
-      this._checkParentType();
+      checkParentType(this._parent);
     }
     this._checkName();
   }
 
-  private _checkParentType(): void {
-    if (typeof ngDevMode === 'undefined' || ngDevMode) {
-      if (
-        !(this._parent instanceof NgModelGroup) &&
-        this._parent instanceof AbstractFormGroupDirective
-      ) {
-        throw formGroupNameException();
-      } else if (!(this._parent instanceof NgModelGroup) && !(this._parent instanceof NgForm)) {
-        throw modelParentException();
-      }
-    }
-  }
-
   private _checkName(): void {
     if (this.options && this.options.name) this.name = this.options.name;
 
@@ -387,3 +374,11 @@ export class NgModel extends NgControl implements OnChanges, OnDestroy {
     return this._parent ? controlPath(controlName, this._parent) : [controlName];
   }
 }
+
+function checkParentType(parent: ControlContainer | null) {
+  if (!(parent instanceof NgModelGroup) && parent instanceof AbstractFormGroupDirective) {
+    throw formGroupNameException();
+  } else if (!(parent instanceof NgModelGroup) && !(parent instanceof NgForm)) {
+    throw modelParentException();
+  }
+}

packages/forms/src/directives/reactive_directives/form_control_name.ts

@@ -213,28 +213,23 @@ export class FormControlName extends NgControl implements OnChanges, OnDestroy {
     return this._parent ? this._parent.formDirective : null;
   }
 
-  private _checkParentType(): void {
-    if (typeof ngDevMode === 'undefined' || ngDevMode) {
-      if (
-        !(this._parent instanceof FormGroupName) &&
-        this._parent instanceof AbstractFormGroupDirective
-      ) {
-        throw ngModelGroupException();
-      } else if (
-        !(this._parent instanceof FormGroupName) &&
-        !(this._parent instanceof FormGroupDirective) &&
-        !(this._parent instanceof FormArrayName)
-      ) {
-        throw controlParentException(this.name);
-      }
-    }
-  }
-
   private _setUpControl() {
     if (typeof ngDevMode === 'undefined' || ngDevMode) {
-      this._checkParentType();
+      checkParentType(this._parent, this.name);
     }
     (this as Writable<this>).control = this.formDirective.addControl(this);
     this._added = true;
   }
 }
+
+function checkParentType(parent: ControlContainer | null, name: string | number | null) {
+  if (!(parent instanceof FormGroupName) && parent instanceof AbstractFormGroupDirective) {
+    throw ngModelGroupException();
+  } else if (
+    !(parent instanceof FormGroupName) &&
+    !(parent instanceof FormGroupDirective) &&
+    !(parent instanceof FormArrayName)
+  ) {
+    throw controlParentException(name);
+  }
+}

packages/forms/src/directives/reactive_directives/form_group_name.ts

@@ -115,7 +115,7 @@ export class FormGroupName extends AbstractFormGroupDirective implements OnInit,
 
   /** @internal */
   override _checkParentType(): void {
-    if (_hasInvalidParent(this._parent) && (typeof ngDevMode === 'undefined' || ngDevMode)) {
+    if (hasInvalidParent(this._parent) && (typeof ngDevMode === 'undefined' || ngDevMode)) {
       throw groupParentException();
     }
   }
@@ -190,8 +190,8 @@ export class FormArrayName extends ControlContainer implements OnInit, OnDestroy
    * @nodoc
    */
   ngOnInit(): void {
-    if (typeof ngDevMode === 'undefined' || ngDevMode) {
-      this._checkParentType();
+    if (hasInvalidParent(this._parent) && (typeof ngDevMode === 'undefined' || ngDevMode)) {
+      throw arrayParentException();
     }
     this.formDirective!.addFormArray(this);
   }
@@ -201,9 +201,7 @@ export class FormArrayName extends ControlContainer implements OnInit, OnDestroy
    * @nodoc
    */
   ngOnDestroy(): void {
-    if (this.formDirective) {
-      this.formDirective.removeFormArray(this);
-    }
+    this.formDirective?.removeFormArray(this);
   }
 
   /**
@@ -230,15 +228,9 @@ export class FormArrayName extends ControlContainer implements OnInit, OnDestroy
   override get path(): string[] {
     return controlPath(this.name == null ? this.name : this.name.toString(), this._parent);
   }
-
-  private _checkParentType(): void {
-    if (_hasInvalidParent(this._parent) && (typeof ngDevMode === 'undefined' || ngDevMode)) {
-      throw arrayParentException();
-    }
-  }
 }
 
-function _hasInvalidParent(parent: ControlContainer): boolean {
+function hasInvalidParent(parent: ControlContainer): boolean {
   return (
     !(parent instanceof FormGroupName) &&
     !(parent instanceof FormGroupDirective) &&