Record selection changes in history (undo)

docs/designers-developers/developers/data/data-core-block-editor.md

@@ -691,7 +691,7 @@ _Returns_
 Returns true if the block corresponding to the specified client ID is
 currently selected but isn't the last of the selected blocks. Here "last"
 refers to the block sequence in the document, _not_ the sequence of
-multi-selection, which is why `state.blockSelection.end` isn't used.
+multi-selection, which is why `state.selectionEnd` isn't used.
 
 _Parameters_
 
@@ -1033,6 +1033,20 @@ _Returns_
 
 -   `Object`: Action object.
 
+<a name="resetSelection" href="#resetSelection">#</a> **resetSelection**
+
+Returns an action object used in signalling that selection state should be
+reset to the specified selection.
+
+_Parameters_
+
+-   _selectionStart_ `WPBlockSelection`: The selection start.
+-   _selectionEnd_ `WPBlockSelection`: The selection end.
+
+_Returns_
+
+-   `Object`: Action object.
+
 <a name="selectBlock" href="#selectBlock">#</a> **selectBlock**
 
 Returns an action object used in signalling that the block with the

docs/designers-developers/developers/data/data-core-editor.md

@@ -358,6 +358,30 @@ _Returns_
 
 -   `Array`: Block list.
 
+<a name="getEditorSelectionEnd" href="#getEditorSelectionEnd">#</a> **getEditorSelectionEnd**
+
+Return the current selection end.
+
+_Parameters_
+
+-   _state_ `Object`: 
+
+_Returns_
+
+-   `WPBlockSelection`: The selection end.
+
+<a name="getEditorSelectionStart" href="#getEditorSelectionStart">#</a> **getEditorSelectionStart**
+
+Return the current selection start.
+
+_Parameters_
+
+-   _state_ `Object`: 
+
+_Returns_
+
+-   `WPBlockSelection`: The selection start.
+
 <a name="getEditorSettings" href="#getEditorSettings">#</a> **getEditorSettings**
 
 Returns the post editor settings.
@@ -1209,6 +1233,19 @@ _Returns_
 
 -   `Object`: Action object
 
+<a name="resetEditorSelection" href="#resetEditorSelection">#</a> **resetEditorSelection**
+
+Returns an action object used to signal that the selection has been updated.
+
+_Parameters_
+
+-   _selectionStart_ `WPBlockSelection`: The selection start.
+-   _selectionEnd_ `WPBlockSelection`: The selection end.
+
+_Returns_
+
+-   `Object`: Action object
+
 <a name="resetPost" href="#resetPost">#</a> **resetPost**
 
 Returns an action object used in signalling that the latest version of the

packages/block-editor/src/components/provider/README.md

@@ -12,6 +12,20 @@ BlockEditorProvider is a component which establishes a new block editing context
 
 The current array of blocks.
 
+### `selectionStart`
+
+* **Type:** `WPBlockSelection`
+* **Required** `no`
+
+The current selection start.
+
+### `selectionEnd`
+
+* **Type:** `WPBlockSelection`
+* **Required** `no`
+
+The current selection end.
+
 ### `onChange`
 
 * **Type:** `Function`
@@ -32,6 +46,13 @@ In the context of an editor, an example usage of this distinction is for managin
 
 A callback invoked when the blocks have been modified in a non-persistent manner. Contrasted with `onChange`, a "non-persistent" change is one which is part of a composed input. Any sequence of updates to the same block attribute are treated as non-persistent, except for the first.
 
+### `onChangeSelection`
+
+* **Type:** `Function`
+* **Required** `no`
+
+A callback invoked when the block selection has been modified.
+
 ### `children`
 
 * **Type:** `WPElement`

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

@@ -23,6 +23,9 @@ class BlockEditorProvider extends Component {
 			updateSettings,
 			value,
 			resetBlocks,
+			selectionStart,
+			selectionEnd,
+			resetSelection,
 			registry,
 		} = this.props;
 
@@ -50,6 +53,10 @@ class BlockEditorProvider extends Component {
 			this.isSyncingOutcomingValue = null;
 			this.isSyncingIncomingValue = value;
 			resetBlocks( value );
+
+			if ( selectionStart && selectionEnd ) {
+				resetSelection( selectionStart, selectionEnd );
+			}
 		}
 	}
 
@@ -78,6 +85,8 @@ class BlockEditorProvider extends Component {
 
 		const {
 			getBlocks,
+			getSelectionStart,
+			getSelectionEnd,
 			isLastBlockChangePersistent,
 			__unstableIsLastBlockChangeIgnored,
 		} = registry.select( 'core/block-editor' );
@@ -89,6 +98,7 @@ class BlockEditorProvider extends Component {
 			const {
 				onChange,
 				onInput,
+				onChangeSelection,
 			} = this.props;
 
 			const newBlocks = getBlocks();
@@ -120,6 +130,14 @@ class BlockEditorProvider extends Component {
 				blocks = newBlocks;
 				isPersistent = newIsPersistent;
 
+				// Selection must be updated first, so it is recorded in history when the content change happens.
+				if ( onChangeSelection ) {
+					onChangeSelection(
+						getSelectionStart(),
+						getSelectionEnd()
+					);
+				}
+
 				if ( isPersistent ) {
 					onChange( blocks );
 				} else {
@@ -142,11 +160,13 @@ export default compose( [
 		const {
 			updateSettings,
 			resetBlocks,
+			resetSelection,
 		} = dispatch( 'core/block-editor' );
 
 		return {
 			updateSettings,
 			resetBlocks,
+			resetSelection,
 		};
 	} ),
 ] )( BlockEditorProvider );

packages/block-editor/src/store/actions.js

@@ -48,6 +48,31 @@ export function resetBlocks( blocks ) {
 	};
 }
 
+/**
+ * @typedef {WPBlockSelection} A block selection object.
+ *
+ * @property {string} clientId     A block client ID.
+ * @property {string} attributeKey A block attribute key.
+ * @property {number} offset       A block attribute offset.
+ */
+
+/**
+ * Returns an action object used in signalling that selection state should be
+ * reset to the specified selection.
+ *
+ * @param {WPBlockSelection} selectionStart The selection start.
+ * @param {WPBlockSelection} selectionEnd   The selection end.
+ *
+ * @return {Object} Action object.
+ */
+export function resetSelection( selectionStart, selectionEnd ) {
+	return {
+		type: 'RESET_SELECTION',
+		selectionStart,
+		selectionEnd,
+	};
+}
+
 /**
  * Returns an action object used in signalling that blocks have been received.
  * Unlike resetBlocks, these should be appended to the existing known set, not