Paragraph: Add LineHeightControl + Attribute (#20775)

* Update emotion library to latest. Adds to block-library package.

* Add LineHeightControl component to block-editor

* Export LineHeightControl as experimental from block-editor

* Hook up LineHeightControl with core Paragraph block

* Improve undefined/reset interactions for line-height attribute

* Refactor store hook usage with LineHeightControl

* Refactor with withLineHeight HOC for Edit and Save components

* Improve reset logic. Simplifies stlye value output.

* Refactor function names and comments

* Fix import/export of new experimental attribute hooks

* Export LineHeightControls and withLineHeight for native

* Adjust mechanism to get block attributes in useBlockAttributes hook

* Add theme support for disable-custom-line-height

* Clarify logic + add comments for lineHeight attribute -> value evaluation

* Simplify CSS output for lineHeight in paragraph block

* Add experimental prefix for disableCustomLineHeight setting

* Add comment for :root based CSS rule

* Removes @emotion from block-library. Refactor to use scss

* Remove withLineHeight HOC abstraction.

Reverted to use inline styles instead of CSS variable for line-height style rendering

* Revert className implementation

Also revert @emotion library versions to master

* Revert @emotion/native from 10.0.23 -> 10.0.22 (to match master)

* Updates package-lock.json

* Fix e2e test to target correct text input

* Reverting package-lock.json

* Provide clientId in dependency array in useSetAttributes hook

* Use CSS variables and a support flag for the line height customization

* Improves handling of "zero" key press

* Update packages/block-editor/src/components/line-height-control/utils.js

Co-Authored-By: Zebulan Stanphill <zebulanstanphill@protonmail.com>

* Remove unused import

* Remove useless hooks file

Co-authored-by: Riad Benguella <benguella@gmail.com>
Co-authored-by: Zebulan Stanphill <zebulanstanphill@protonmail.com>

lib/client-assets.php

@@ -647,6 +647,19 @@ function gutenberg_extend_settings_block_patterns( $settings ) {
 }
 add_filter( 'block_editor_settings', 'gutenberg_extend_settings_block_patterns', 0 );
 
+/**
+ * Extends block editor settings to determine whether to use custom line height controls.
+ * Currently experimental.
+ *
+ * @param array $settings Default editor settings.
+ *
+ * @return array Filtered editor settings.
+ */
+function gutenberg_extend_settings_custom_line_height( $settings ) {
+	$settings['__experimentalDisableCustomLineHeight'] = get_theme_support( 'disable-custom-line-height' );
+	return $settings;
+}
+add_filter( 'block_editor_settings', 'gutenberg_extend_settings_custom_line_height' );
 
 /*
  * Register default patterns if not registered in Core already.

packages/block-editor/src/components/index.js

@@ -34,6 +34,7 @@ export { default as InnerBlocks } from './inner-blocks';
 export { default as InspectorAdvancedControls } from './inspector-advanced-controls';
 export { default as InspectorControls } from './inspector-controls';
 export { default as __experimentalLinkControl } from './link-control';
+export { default as __experimentalLineHeightControl } from './line-height-control';
 export { default as MediaReplaceFlow } from './media-replace-flow';
 export { default as MediaPlaceholder } from './media-placeholder';
 export { default as MediaUpload } from './media-upload';

packages/block-editor/src/components/index.native.js

@@ -11,6 +11,7 @@ export * from './font-sizes';
 export { default as AlignmentToolbar } from './alignment-toolbar';
 export { default as InnerBlocks } from './inner-blocks';
 export { default as InspectorControls } from './inspector-controls';
+export { default as __experimentalLineHeightControl } from './line-height-control';
 export { default as PlainText } from './plain-text';
 export {
 	default as RichText,

packages/block-editor/src/components/line-height-control/index.js

@@ -0,0 +1,88 @@
+/**
+ * WordPress dependencies
+ */
+import { __ } from '@wordpress/i18n';
+import { TextControl } from '@wordpress/components';
+import { ZERO } from '@wordpress/keycodes';
+
+/**
+ * Internal dependencies
+ */
+import {
+	BASE_DEFAULT_VALUE,
+	RESET_VALUE,
+	STEP,
+	useIsLineHeightControlsDisabled,
+	isLineHeightDefined,
+} from './utils';
+
+export default function LineHeightControl( { value: lineHeight, onChange } ) {
+	const isDisabled = useIsLineHeightControlsDisabled();
+	const isDefined = isLineHeightDefined( lineHeight );
+
+	// Don't render the controls if disabled by editor settings
+	if ( isDisabled ) {
+		return null;
+	}
+
+	const handleOnKeyDown = ( event ) => {
+		const { keyCode } = event;
+
+		if ( keyCode === ZERO && ! isDefined ) {
+			/**
+			 * Prevents the onChange callback from firing, which prevents
+			 * the logic from assuming the change was triggered from
+			 * an input arrow CLICK.
+			 */
+			event.preventDefault();
+			onChange( '0' );
+		}
+	};
+
+	const handleOnChange = ( nextValue ) => {
+		// Set the next value without modification if lineHeight has been defined
+		if ( isDefined ) {
+			onChange( nextValue );
+			return;
+		}
+
+		// Otherwise...
+		/**
+		 * The following logic handles the initial up/down arrow CLICK of the
+		 * input element. This is so that the next values (from an undefined value state)
+		 * are more better suited for line-height rendering.
+		 */
+		let adjustedNextValue = nextValue;
+
+		switch ( nextValue ) {
+			case `${ STEP }`:
+				// Increment by step value
+				adjustedNextValue = BASE_DEFAULT_VALUE + STEP;
+				break;
+			case '0':
+				// Decrement by step value
+				adjustedNextValue = BASE_DEFAULT_VALUE - STEP;
+				break;
+		}
+
+		onChange( adjustedNextValue );
+	};
+
+	const value = isDefined ? lineHeight : RESET_VALUE;
+
+	return (
+		<div className="block-editor-line-height-control">
+			<TextControl
+				autoComplete="off"
+				onKeyDown={ handleOnKeyDown }
+				onChange={ handleOnChange }
+				label={ __( 'Line height' ) }
+				placeholder={ BASE_DEFAULT_VALUE }
+				step={ STEP }
+				type="number"
+				value={ value }
+				min={ 0 }
+			/>
+		</div>
+	);
+}

packages/block-editor/src/components/line-height-control/style.scss

@@ -0,0 +1,8 @@
+.block-editor-line-height-control {
+	margin-bottom: 24px;
+
+	input {
+		display: block;
+		max-width: 60px;
+	}
+}

packages/block-editor/src/components/line-height-control/utils.js

@@ -0,0 +1,44 @@
+/**
+ * WordPress dependencies
+ */
+import { useSelect } from '@wordpress/data';
+
+export const BASE_DEFAULT_VALUE = 1.5;
+export const STEP = 0.1;
+/**
+ * There are varying value types within LineHeightControl:
+ *
+ * {undefined} Initial value. No changes from the user.
+ * {string} Input value. Value consumed/outputted by the input. Empty would be ''.
+ * {number} Block attribute type. Input value needs to be converted for attribute setting.
+ *
+ * Note: If the value is undefined, the input requires it to be an empty string ('')
+ * in order to be considered "controlled" by props (rather than internal state).
+ */
+export const RESET_VALUE = '';
+
+/**
+ * Retrieves whether custom lineHeight controls should be disabled from editor settings.
+ *
+ * @return {boolean} Whether lineHeight controls should be disabled.
+ */
+export function useIsLineHeightControlsDisabled() {
+	const isDisabled = useSelect( ( select ) => {
+		const { getSettings } = select( 'core/block-editor' );
+
+		return !! getSettings().__experimentalDisableCustomLineHeight;
+	}, [] );
+
+	return isDisabled;
+}
+
+/**
+ * Determines if the lineHeight attribute has been properly defined.
+ *
+ * @param {any} lineHeight The value to check.
+ *
+ * @return {boolean} Whether the lineHeight attribute is valid.
+ */
+export function isLineHeightDefined( lineHeight ) {
+	return lineHeight !== undefined && lineHeight !== RESET_VALUE;
+}

packages/block-editor/src/hooks/color.js

@@ -2,7 +2,6 @@
  * External dependencies
  */
 import classnames from 'classnames';
-import { pickBy, isEqual, isObject, identity, mapValues } from 'lodash';
 
 /**
  * WordPress dependencies
@@ -26,22 +25,10 @@ import PanelColorSettings from '../components/panel-color-settings';
 import ContrastChecker from '../components/contrast-checker';
 import InspectorControls from '../components/inspector-controls';
 import { getBlockDOMNode } from '../utils/dom';
+import { cleanEmptyObject } from './utils';
 
 export const COLOR_SUPPORT_KEY = '__experimentalColor';
 
-export const cleanEmptyObject = ( object ) => {
-	if ( ! isObject( object ) ) {
-		return object;
-	}
-	const cleanedNestedObjects = pickBy(
-		mapValues( object, cleanEmptyObject ),
-		identity
-	);
-	return isEqual( cleanedNestedObjects, {} )
-		? undefined
-		: cleanedNestedObjects;
-};
-
 /**
  * Filters registered block settings, extending attributes to include
  * `backgroundColor` and `textColor` attribute.

packages/block-editor/src/hooks/line-height.js

@@ -0,0 +1,64 @@
+/**
+ * WordPress dependencies
+ */
+import { addFilter } from '@wordpress/hooks';
+import { hasBlockSupport } from '@wordpress/blocks';
+import { createHigherOrderComponent } from '@wordpress/compose';
+import { PanelBody } from '@wordpress/components';
+import { __ } from '@wordpress/i18n';
+
+/**
+ * Internal dependencies
+ */
+import LineHeightControl from '../components/line-height-control';
+import InspectorControls from '../components/inspector-controls';
+import { cleanEmptyObject } from './utils';
+
+export const LINE_HEIGHT_SUPPRT_KEY = '__experimentalLineHeight';
+
+/**
+ * Override the default edit UI to include new inspector controls for block
+ * color, if block defines support.
+ *
+ * @param  {Function} BlockEdit Original component
+ * @return {Function}           Wrapped component
+ */
+export const withBlockControls = createHigherOrderComponent(
+	( BlockEdit ) => ( props ) => {
+		const { name: blockName } = props;
+		if ( ! hasBlockSupport( blockName, LINE_HEIGHT_SUPPRT_KEY ) ) {
+			return <BlockEdit key="edit" { ...props } />;
+		}
+		const { style } = props.attributes;
+		const onChange = ( newLineHeightValue ) => {
+			const newStyle = {
+				...style,
+				typography: {
+					lineHeight: newLineHeightValue,
+				},
+			};
+			props.setAttributes( {
+				style: cleanEmptyObject( newStyle ),
+			} );
+		};
+
+		return [
+			<InspectorControls key="control">
+				<PanelBody title={ __( 'Typography' ) }>
+					<LineHeightControl
+						value={ style?.typography?.lineHeight }
+						onChange={ onChange }
+					/>
+				</PanelBody>
+			</InspectorControls>,
+			<BlockEdit key="edit" { ...props } />,
+		];
+	},
+	'withToolbarControls'
+);
+
+addFilter(
+	'editor.BlockEdit',
+	'core/color/with-block-controls',
+	withBlockControls
+);

packages/block-editor/src/hooks/style.js

@@ -13,8 +13,9 @@ import { hasBlockSupport } from '@wordpress/blocks';
  * Internal dependencies
  */
 import { COLOR_SUPPORT_KEY } from './color';
+import { LINE_HEIGHT_SUPPRT_KEY } from './line-height';
 
-const styleSupportKeys = [ COLOR_SUPPORT_KEY ];
+const styleSupportKeys = [ COLOR_SUPPORT_KEY, LINE_HEIGHT_SUPPRT_KEY ];
 
 const hasStyleSupport = ( blockType ) =>
 	styleSupportKeys.some( ( key ) => hasBlockSupport( blockType, key ) );

packages/block-editor/src/hooks/test/color.js

@@ -1,7 +1,7 @@
 /**
  * Internal dependencies
  */
-import { cleanEmptyObject } from '../color';
+import { cleanEmptyObject } from '../utils';
 
 describe( 'cleanEmptyObject', () => {
 	it( 'should remove nested keys', () => {

packages/block-editor/src/hooks/utils.js

@@ -0,0 +1,23 @@
+/**
+ * External dependencies
+ */
+import { pickBy, isEqual, isObject, identity, mapValues } from 'lodash';
+
+/**
+ * Removed undefined values from nested object.
+ *
+ * @param {*} object
+ * @return {*} Object cleaned from undefined values
+ */
+export const cleanEmptyObject = ( object ) => {
+	if ( ! isObject( object ) ) {
+		return object;
+	}
+	const cleanedNestedObjects = pickBy(
+		mapValues( object, cleanEmptyObject ),
+		identity
+	);
+	return isEqual( cleanedNestedObjects, {} )
+		? undefined
+		: cleanedNestedObjects;
+};

packages/block-editor/src/style.scss

@@ -27,6 +27,7 @@
 @import "./components/contrast-checker/style.scss";
 @import "./components/default-block-appender/style.scss";
 @import "./components/link-control/style.scss";
+@import "./components/line-height-control/style.scss";
 @import "./components/image-size-control/style.scss";
 @import "./components/inner-blocks/style.scss";
 @import "./components/inserter-list-item/style.scss";

packages/block-library/src/paragraph/block.json

@@ -26,7 +26,10 @@
 		},
 		"direction": {
 			"type": "string",
-			"enum": [ "ltr", "rtl" ]
+			"enum": [
+				"ltr",
+				"rtl"
+			]
 		}
 	}
 }

packages/block-library/src/paragraph/edit.js

@@ -80,13 +80,19 @@ function ParagraphBlock( {
 	setAttributes,
 	setFontSize,
 } ) {
-	const { align, content, dropCap, placeholder, direction } = attributes;
+	const { align, content, direction, dropCap, placeholder } = attributes;
 
 	const ref = useRef();
 	const dropCapMinimumHeight = useDropCapMinimumHeight( dropCap, [
 		fontSize.size,
 	] );
 
+	const styles = {
+		fontSize: fontSize.size ? `${ fontSize.size }px` : undefined,
+		direction,
+		minHeight: dropCapMinimumHeight,
+	};
+
 	return (
 		<>
 			<BlockControls>
@@ -132,11 +138,7 @@ function ParagraphBlock( {
 					[ `has-text-align-${ align }` ]: align,
 					[ fontSize.class ]: fontSize.class,
 				} ) }
-				style={ {
-					fontSize: fontSize.size ? fontSize.size + 'px' : undefined,
-					direction,
-					minHeight: dropCapMinimumHeight,
-				} }
+				style={ styles }
 				value={ content }
 				onChange={ ( newContent ) =>
 					setAttributes( { content: newContent } )

packages/block-library/src/paragraph/index.js

@@ -41,6 +41,7 @@ export const settings = {
 		__unstablePasteTextInline: true,
 		lightBlockWrapper: true,
 		__experimentalColor: true,
+		__experimentalLineHeight: true,
 	},
 	__experimentalLabel( attributes, { context } ) {
 		if ( context === 'accessibility' ) {

packages/block-library/src/paragraph/style.scss

@@ -1,6 +1,7 @@
 :root p {
 	background-color: var(--wp--color--background);
 	color: var(--wp--color--text);
+	line-height: var(--wp--typography--line-height);
 }
 
 .is-small-text {

packages/e2e-tests/specs/editor/various/embedding.test.js

@@ -307,7 +307,7 @@ describe( 'Embedding content', () => {
 		await page.keyboard.type( 'Hello there!' );
 		await publishPost();
 		const postUrl = await page.$eval(
-			'[id^=inspector-text-control-]',
+			'.editor-post-publish-panel [id^=inspector-text-control-]',
 			( el ) => el.value
 		);