fix(form-core): choice-group initialization values + null support

.changeset/old-starfishes-glow.md

@@ -0,0 +1,6 @@
+---
+'@lion/form-core': patch
+---
+
+- form-core: pending initialization values in order of execution
+- form-core: choiceGroup null and undefined values support

packages/form-core/src/choice-group/ChoiceGroupMixin.js

@@ -53,8 +53,8 @@ const ChoiceGroupMixinImplementation = superclass =>
       };
 
       if (this.__isInitialModelValue) {
-        this.__isInitialModelValue = false;
         this.registrationComplete.then(() => {
+          this.__isInitialModelValue = false;
           this._setCheckedElements(value, checkCondition);
           this.requestUpdate('modelValue', this.__oldModelValue);
         });
@@ -89,8 +89,8 @@ const ChoiceGroupMixinImplementation = superclass =>
       const checkCondition = (el, val) => el.serializedValue.value === val;
 
       if (this.__isInitialSerializedValue) {
-        this.__isInitialSerializedValue = false;
         this.registrationComplete.then(() => {
+          this.__isInitialSerializedValue = false;
           this._setCheckedElements(value, checkCondition);
           this.requestUpdate('serializedValue');
         });
@@ -116,8 +116,8 @@ const ChoiceGroupMixinImplementation = superclass =>
       const checkCondition = (el, val) => el.formattedValue === val;
 
       if (this.__isInitialFormattedValue) {
-        this.__isInitialFormattedValue = false;
         this.registrationComplete.then(() => {
+          this.__isInitialFormattedValue = false;
           this._setCheckedElements(value, checkCondition);
         });
       } else {
@@ -307,6 +307,12 @@ const ChoiceGroupMixinImplementation = superclass =>
      * @protected
      */
     _setCheckedElements(value, check) {
+      if (value === null || value === undefined) {
+        // Uncheck all
+        // eslint-disable-next-line no-return-assign, no-param-reassign
+        this.formElements.forEach(fe => (fe.checked = false));
+        return;
+      }
       for (let i = 0; i < this.formElements.length; i += 1) {
         if (this.multipleChoice) {
           let valueIsIncluded = value.includes(this.formElements[i].modelValue.value);

packages/form-core/test-suites/choice-group/ChoiceGroupMixin.suite.js

@@ -2,7 +2,7 @@ import { LitElement } from '@lion/core';
 import { LionInput } from '@lion/input';
 import '@lion/fieldset/define';
 import { FormGroupMixin, Required } from '@lion/form-core';
-import { expect, html, fixture, unsafeStatic } from '@open-wc/testing';
+import { expect, html, fixture, fixtureSync, unsafeStatic } from '@open-wc/testing';
 import { ChoiceGroupMixin } from '../../src/choice-group/ChoiceGroupMixin.js';
 import { ChoiceInputMixin } from '../../src/choice-group/ChoiceInputMixin.js';
 
@@ -246,6 +246,72 @@ export function runChoiceGroupMixinSuite({ parentTagString, childTagString, choi
       expect(el.formElements[2].checked).to.be.true;
     });
 
+    it('correctly handles modelValue being set before registrationComplete', async () => {
+      const el = /** @type {ChoiceInputGroup} */ (fixtureSync(html`
+        <${parentTag} name="gender[]" .modelValue=${null}>
+          <${childTag} .choiceValue=${'male'}></${childTag}>
+          <${childTag} .choiceValue=${'female'}></${childTag}>
+          <${childTag} .choiceValue=${'other'}></${childTag}>
+        </${parentTag}>
+      `));
+
+      if (cfg.choiceType === 'single') {
+        el.modelValue = 'other';
+        await el.registrationComplete;
+        expect(el.modelValue).to.equal('other');
+      } else {
+        el.modelValue = ['other'];
+        await el.registrationComplete;
+        expect(el.modelValue).to.deep.equal(['other']);
+      }
+    });
+
+    it('correctly handles serializedValue being set before registrationComplete', async () => {
+      const el = /** @type {ChoiceInputGroup} */ (fixtureSync(html`
+        <${parentTag} name="gender[]" .serializedValue=${null}>
+          <${childTag} .choiceValue=${'male'}></${childTag}>
+          <${childTag} .choiceValue=${'female'}></${childTag}>
+          <${childTag} .choiceValue=${'other'}></${childTag}>
+        </${parentTag}>
+      `));
+
+      if (cfg.choiceType === 'single') {
+        // @ts-expect-error
+        el.serializedValue = 'other';
+        await el.registrationComplete;
+        expect(el.serializedValue).to.equal('other');
+      } else {
+        // @ts-expect-error
+        el.serializedValue = ['other'];
+        await el.registrationComplete;
+        expect(el.serializedValue).to.deep.equal(['other']);
+      }
+    });
+
+    it('can handle null and undefined modelValues', async () => {
+      const el = /** @type {ChoiceInputGroup} */ (await fixture(html`
+        <${parentTag} name="gender[]" .modelValue=${null}>
+          <${childTag} .choiceValue=${'male'}></${childTag}>
+          <${childTag} .choiceValue=${'female'}></${childTag}>
+          <${childTag} .choiceValue=${'other'}></${childTag}>
+        </${parentTag}>
+      `));
+
+      if (cfg.choiceType === 'single') {
+        expect(el.modelValue).to.equal('');
+      } else {
+        expect(el.modelValue).to.deep.equal([]);
+      }
+
+      el.modelValue = undefined;
+      await el.updateComplete;
+      if (cfg.choiceType === 'single') {
+        expect(el.modelValue).to.equal('');
+      } else {
+        expect(el.modelValue).to.deep.equal([]);
+      }
+    });
+
     it('can handle complex data via choiceValue', async () => {
       const date = new Date(2018, 11, 24, 10, 33, 30, 0);
 

packages/form-core/types/FormControlMixinTypes.d.ts

@@ -123,7 +123,7 @@ export declare class FormControlHost {
    * (think of an amount-input with a currency select box next to it), can set this
    * to true to hide private internals in the formPath.
    */
-  _isRepropagationEndpoint: boolean;
+  protected _isRepropagationEndpoint: boolean;
 
   connectedCallback(): void;
   updated(changedProperties: import('@lion/core').PropertyValues): void;