Fix: Another paragraph is inserted, inside InnerBlocks.

packages/editor/src/components/inner-blocks/index.js

@@ -23,7 +23,9 @@ import { withBlockEditContext } from '../block-edit/context';
 class InnerBlocks extends Component {
 	constructor() {
 		super( ...arguments );
-
+		this.state = {
+			templateInProcess: !! this.props.template,
+		};
 		this.updateNestedSettings();
 	}
 
@@ -39,7 +41,12 @@ class InnerBlocks extends Component {
 		const { innerBlocks } = this.props.block;
 		// only synchronize innerBlocks with template if innerBlocks are empty or a locking all exists
 		if ( innerBlocks.length === 0 || this.getTemplateLock() === 'all' ) {
-			return 	this.synchronizeBlocksWithTemplate();
+			this.synchronizeBlocksWithTemplate();
+		}
+		if ( this.state.templateInProcess ) {
+			this.setState( {
+				templateInProcess: false,
+			} );
 		}
 	}
 
@@ -93,23 +100,22 @@ class InnerBlocks extends Component {
 	render() {
 		const {
 			clientId,
-			allowedBlocks,
-			templateLock,
-			template,
 			isSmallScreen,
 			isSelectedBlockInRoot,
 		} = this.props;
+		const { templateInProcess } = this.state;
 
 		const classes = classnames( 'editor-inner-blocks', {
 			'has-overlay': isSmallScreen && ! isSelectedBlockInRoot,
 		} );
 
 		return (
 			<div className={ classes }>
-				<BlockList
-					rootClientId={ clientId }
-					{ ...{ allowedBlocks, templateLock, template } }
-				/>
+				{ ! templateInProcess && (
+					<BlockList
+						rootClientId={ clientId }
+					/>
+				) }
 			</div>
 		);
 	}

test/e2e/specs/__snapshots__/container-blocks.test.js.snap

@@ -8,16 +8,20 @@ exports[`Container block without paragraph support ensures we can use the altern
 <!-- /wp:test/container-without-paragraph -->"
 `;
 
+exports[`InnerBlocks Template Sync Ensure inner block writing flow works as expected without additional paragraphs added 1`] = `
+"<!-- wp:test/test-inner-blocks-paragraph-placeholder -->
+<!-- wp:paragraph {\\"placeholder\\":\\"Content…\\",\\"fontSize\\":\\"large\\"} -->
+<p class=\\"has-large-font-size\\">Test Paragraph</p>
+<!-- /wp:paragraph -->
+<!-- /wp:test/test-inner-blocks-paragraph-placeholder -->"
+`;
+
 exports[`InnerBlocks Template Sync Ensures blocks without locking are kept intact even if they do not match the template  1`] = `
 "<!-- wp:test/test-inner-blocks-no-locking -->
 <!-- wp:paragraph {\\"fontSize\\":\\"large\\"} -->
 <p class=\\"has-large-font-size\\">Content…</p>
 <!-- /wp:paragraph -->
 
-<!-- wp:paragraph -->
-<p></p>
-<!-- /wp:paragraph -->
-
 <!-- wp:paragraph -->
 <p>added paragraph</p>
 <!-- /wp:paragraph -->

test/e2e/specs/container-blocks.test.js

@@ -49,6 +49,15 @@ describe( 'InnerBlocks Template Sync', () => {
 		await insertBlockAndAddParagraphInside( 'Test InnerBlocks locking all', 'test/test-inner-blocks-locking-all' );
 		expect( await getEditedPostContent() ).toMatchSnapshot();
 	} );
+
+	it( 'Ensure inner block writing flow works as expected without additional paragraphs added', async () => {
+		const TEST_BLOCK_NAME = 'Test Inner Blocks Paragraph Placeholder';
+
+		await insertBlock( TEST_BLOCK_NAME );
+		await page.keyboard.type( 'Test Paragraph' );
+
+		expect( await getEditedPostContent() ).toMatchSnapshot();
+	} );
 } );
 
 describe( 'Container block without paragraph support', () => {

test/e2e/test-plugins/inner-blocks-templates/index.js

@@ -10,6 +10,13 @@
 		} ],
 	];
 
+	var TEMPLATE_PARAGRAPH_PLACEHOLDER = [
+		[ 'core/paragraph', {
+			fontSize: 'large',
+			placeholder: 'Content…',
+		} ],
+	];
+
 	var save = function() {
 		return el( InnerBlocks.Content );
 	};
@@ -48,4 +55,21 @@
 
 		save,
 	} );
+
+	registerBlockType( 'test/test-inner-blocks-paragraph-placeholder', {
+		title: 'Test Inner Blocks Paragraph Placeholder',
+		icon: 'cart',
+		category: 'common',
+
+		edit: function( props ) {
+			return el(
+					InnerBlocks,
+					{
+						template: TEMPLATE_PARAGRAPH_PLACEHOLDER,
+					}
+			);
+		},
+
+		save,
+	} );
 } )();