Merge bb014d9 into d248712

src/model/operation/transform.js

@@ -1220,13 +1220,17 @@ setTransformation( MergeOperation, MergeOperation, ( a, b, context ) => {
 	// Doing this instead of returning `NoOperation` allows for a correct undo later.
 	//
 	if ( a.sourcePosition.isEqual( b.sourcePosition ) && a.targetPosition.isEqual( b.targetPosition ) ) {
-		const path = b.graveyardPosition.path.slice();
-		path.push( 0 );
+		if ( context.bWasUndone ) {
+			const path = b.graveyardPosition.path.slice();
+			path.push( 0 );
 
-		a.sourcePosition = new Position( b.graveyardPosition.root, path );
-		a.howMany = 0;
+			a.sourcePosition = new Position( b.graveyardPosition.root, path );
+			a.howMany = 0;
 
-		return [ a ];
+			return [ a ];
+		} else {
+			return [ new NoOperation( 0 ) ];
+		}
 	}
 
 	// The default case.

tests/model/operation/transform/split.js

@@ -317,6 +317,25 @@ describe( 'transform', () => {
 				expectClients( '<paragraph>Foo</paragraph>' );
 			} );
 
+			it( 'text in same position, then undo and redo', () => {
+				john.setData( '<paragraph>F[]oo</paragraph>' );
+				kate.setData( '<paragraph>F[]oo</paragraph>' );
+
+				john.split();
+				kate.split();
+
+				syncClients();
+
+				john.undo();
+
+				syncClients();
+
+				kate.undo();
+				kate.redo();
+
+				expectClients( '<paragraph>Foo</paragraph>' );
+			} );
+
 			it( 'text in different path', () => {
 				john.setData( '<paragraph>F[]oo</paragraph><paragraph>Bar</paragraph>' );
 				kate.setData( '<paragraph>Foo</paragraph><paragraph>B[]ar</paragraph>' );

tests/model/operation/transform/utils.js

@@ -189,6 +189,10 @@ export class Client {
 		this._processExecute( 'undo' );
 	}
 
+	redo() {
+		this._processExecute( 'redo' );
+	}
+
 	_processExecute( commandName, commandArgs ) {
 		const oldVersion = this.document.version;