feat: update label to use element internals custom states for styling

change/@fluentui-web-components-e7635a3f-6231-44e9-9ab4-bc1fdb86052c.json

@@ -0,0 +1,7 @@
+{
+  "type": "prerelease",
+  "comment": "update label to use element internals custom states for styling",
+  "packageName": "@fluentui/web-components",
+  "email": "[email protected]",
+  "dependentChangeType": "patch"
+}

packages/web-components/docs/api-report.md

@@ -2146,9 +2146,14 @@ export const ImageTemplate: ElementViewTemplate<Image_2>;
 // @public
 export class Label extends FASTElement {
     disabled: boolean;
+    disabledChanged(prev: boolean | undefined, next: boolean | undefined): void;
+    // @internal
+    elementInternals: ElementInternals;
     required: boolean;
     size?: LabelSize;
+    sizeChanged(prev: LabelSize | undefined, next: LabelSize | undefined): void;
     weight?: LabelWeight;
+    weightChanged(prev: LabelWeight | undefined, next: LabelWeight | undefined): void;
 }
 
 // @public
@@ -2883,9 +2888,11 @@ export const spacingVerticalXXXL = "var(--spacingVerticalXXXL)";
 export class Spinner extends FASTElement {
     constructor();
     appearance?: SpinnerAppearance;
+    appearanceChanged(prev: SpinnerAppearance | undefined, next: SpinnerAppearance | undefined): void;
     // @internal
-    protected elementInternals: ElementInternals;
+    elementInternals: ElementInternals;
     size?: SpinnerSize;
+    sizeChanged(prev: SpinnerSize | undefined, next: SpinnerSize | undefined): void;
 }
 
 // @public

packages/web-components/src/label/label.spec.ts

@@ -21,34 +21,31 @@ test.describe('Label', () => {
     await page.close();
   });
 
-  test('should set default attribute values', async () => {
-    await expect(element).toHaveAttribute('size', 'medium');
-    await expect(element).toHaveJSProperty('size', 'medium');
-
-    await expect(element).toHaveAttribute('weight', 'regular');
-    await expect(element).toHaveJSProperty('weight', 'regular');
-  });
-
   test('should reflect size attribute', async () => {
     await element.evaluate((node: Label) => {
       node.size = 'small';
     });
 
     await expect(element).toHaveAttribute('size', 'small');
     await expect(element).toHaveJSProperty('size', 'small');
+    expect(await element.evaluate((node: Label) => node.elementInternals.states.has('small'))).toBe(true);
 
     await element.evaluate((node: Label) => {
       node.size = 'medium';
     });
 
     await expect(element).toHaveAttribute('size', 'medium');
     await expect(element).toHaveJSProperty('size', 'medium');
+    expect(await element.evaluate((node: Label) => node.elementInternals.states.has('small'))).toBe(false);
+    expect(await element.evaluate((node: Label) => node.elementInternals.states.has('medium'))).toBe(true);
 
     await element.evaluate((node: Label) => {
       node.size = 'large';
     });
     await expect(element).toHaveAttribute('size', 'large');
     await expect(element).toHaveJSProperty('size', 'large');
+    expect(await element.evaluate((node: Label) => node.elementInternals.states.has('medium'))).toBe(false);
+    expect(await element.evaluate((node: Label) => node.elementInternals.states.has('large'))).toBe(true);
   });
 
   test('should reflect weight attribute', async () => {
@@ -57,12 +54,15 @@ test.describe('Label', () => {
     });
     await expect(element).toHaveAttribute('weight', 'regular');
     await expect(element).toHaveJSProperty('weight', 'regular');
+    expect(await element.evaluate((node: Label) => node.elementInternals.states.has('regular'))).toBe(true);
 
     await element.evaluate((node: Label) => {
       node.weight = 'semibold';
     });
     await expect(element).toHaveAttribute('weight', 'semibold');
     await expect(element).toHaveJSProperty('weight', 'semibold');
+    expect(await element.evaluate((node: Label) => node.elementInternals.states.has('regular'))).toBe(false);
+    expect(await element.evaluate((node: Label) => node.elementInternals.states.has('semibold'))).toBe(true);
   });
 
   test('should reflect disabled attribute', async () => {
@@ -74,6 +74,7 @@ test.describe('Label', () => {
 
     await expect(element).toHaveAttribute('disabled', '');
     await expect(element).toHaveJSProperty('disabled', true);
+    expect(await element.evaluate((node: Label) => node.elementInternals.states.has('disabled'))).toBe(true);
   });
 
   test('should reflect required attribute and show asterisk', async () => {
@@ -102,42 +103,4 @@ test.describe('Label', () => {
     await expect(element).toHaveJSProperty('required', false);
     await expect(asterisk).toBeHidden();
   });
-
-  test('should reflect changes in size, weight, disabled, and required attributes', async () => {
-    await root.evaluate(node => {
-      node.innerHTML = /* html */ `
-                <fluent-label size="medium" weight="regular">Label</fluent-label>
-            `;
-    });
-    await expect(element).toHaveAttribute('size', 'medium');
-    await expect(element).toHaveJSProperty('size', 'medium');
-
-    await expect(element).toHaveAttribute('weight', 'regular');
-    await expect(element).toHaveJSProperty('weight', 'regular');
-
-    await expect(element).not.toHaveAttribute('disabled', '');
-    await expect(element).toHaveJSProperty('disabled', false);
-
-    await expect(element).not.toHaveAttribute('required', '');
-    await expect(element).toHaveJSProperty('required', false);
-
-    await element.evaluate((node: Label) => {
-      node.size = 'large';
-      node.weight = 'semibold';
-      node.disabled = true;
-      node.required = true;
-    });
-
-    await expect(element).toHaveAttribute('size', 'large');
-    await expect(element).toHaveJSProperty('size', 'large');
-
-    await expect(element).toHaveAttribute('weight', 'semibold');
-    await expect(element).toHaveJSProperty('weight', 'semibold');
-
-    await expect(element).toHaveAttribute('disabled', '');
-    await expect(element).toHaveJSProperty('disabled', true);
-
-    await expect(element).toHaveAttribute('required', '');
-    await expect(element).toHaveJSProperty('required', true);
-  });
 });

packages/web-components/src/label/label.styles.ts

@@ -15,6 +15,7 @@ import {
   lineHeightBase400,
   spacingHorizontalXS,
 } from '../theme/design-tokens.js';
+import { largeState, smallState } from '../styles/states/index.js';
 
 /** Label styles
  * @public
@@ -37,23 +38,23 @@ export const styles = css`
     margin-inline-start: ${spacingHorizontalXS};
   }
 
-  :host([size='small']) {
+  :host(${smallState}) {
     font-size: ${fontSizeBase200};
     line-height: ${lineHeightBase200};
   }
 
-  :host([size='large']) {
+  :host(${largeState}) {
     font-size: ${fontSizeBase400};
     line-height: ${lineHeightBase400};
   }
 
-  :host([size='large']),
-  :host([weight='semibold']) {
+  :host(${largeState}),
+  :host(:is([state--semibold], :state(semibold))) {
     font-weight: ${fontWeightSemibold};
   }
 
-  :host([disabled]),
-  :host([disabled]) .asterisk {
+  :host(:is([state--disabled], :state(disabled))),
+  :host(:is([state--disabled], :state(disabled))) .asterisk {
     color: ${colorNeutralForegroundDisabled};
   }
 `;

packages/web-components/src/label/label.ts

@@ -1,11 +1,19 @@
 import { attr, FASTElement } from '@microsoft/fast-element';
+import { toggleState } from '../utils/element-internals.js';
 import { LabelSize, LabelWeight } from './label.options.js';
 
 /**
  * The base class used for constructing a fluent-label custom element
  * @public
  */
 export class Label extends FASTElement {
+  /**
+   * The internal {@link https://developer.mozilla.org/docs/Web/API/ElementInternals | `ElementInternals`} instance for the component.
+   *
+   * @internal
+   */
+  public elementInternals: ElementInternals = this.attachInternals();
+
   /**
    * 	Specifies font size of a label
    *
@@ -16,6 +24,20 @@ export class Label extends FASTElement {
   @attr
   public size?: LabelSize;
 
+  /**
+   * Handles changes to size attribute custom states
+   * @param prev - the previous state
+   * @param next - the next state
+   */
+  public sizeChanged(prev: LabelSize | undefined, next: LabelSize | undefined) {
+    if (prev) {
+      toggleState(this.elementInternals, `${prev}`, false);
+    }
+    if (next) {
+      toggleState(this.elementInternals, `${next}`, true);
+    }
+  }
+
   /**
    * 	Specifies font weight of a label
    *
@@ -26,6 +48,20 @@ export class Label extends FASTElement {
   @attr
   public weight?: LabelWeight;
 
+  /**
+   * Handles changes to weight attribute custom states
+   * @param prev - the previous state
+   * @param next - the next state
+   */
+  public weightChanged(prev: LabelWeight | undefined, next: LabelWeight | undefined) {
+    if (prev) {
+      toggleState(this.elementInternals, `${prev}`, false);
+    }
+    if (next) {
+      toggleState(this.elementInternals, `${next}`, true);
+    }
+  }
+
   /**
    * 	Specifies styles for label when associated input is disabled
    *
@@ -36,6 +72,15 @@ export class Label extends FASTElement {
   @attr({ mode: 'boolean' })
   public disabled: boolean = false;
 
+  /**
+   * Handles changes to disabled attribute custom states
+   * @param prev - the previous state
+   * @param next - the next state
+   */
+  public disabledChanged(prev: boolean | undefined, next: boolean | undefined) {
+    toggleState(this.elementInternals, 'disabled', next);
+  }
+
   /**
    * 	Specifies styles for label when associated input is a required field
    *