Add support for arrays

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

@@ -56,12 +56,17 @@ export function kebabCase( str ) {
 
 /**
  * Clones an object.
+ * Arrays are also cloned as arrays.
  * Non-object values are returned unchanged.
  *
  * @param {*} object Object to clone.
  * @return {*} Cloned object, or original literal non-object value.
  */
 function cloneObject( object ) {
+	if ( Array.isArray( object ) ) {
+		return object.map( cloneObject );
+	}
+
 	if ( object && typeof object === 'object' ) {
 		return {
 			...Object.fromEntries(
@@ -79,7 +84,7 @@ function cloneObject( object ) {
 /**
  * Immutably sets a value inside an object. Like `lodash#set`, but returning a
  * new object. Treats nullish initial values as empty objects. Clones any
- * nested objects.
+ * nested objects. Supports arrays, too.
  *
  * @param {Object}              object Object to set a value in.
  * @param {number|string|Array} path   Path in the object to modify.
@@ -92,7 +97,11 @@ export function setImmutably( object, path, value ) {
 
 	normalizedPath.reduce( ( acc, key, i ) => {
 		if ( acc[ key ] === undefined ) {
-			acc[ key ] = {};
+			if ( Number.isInteger( path[ i + 1 ] ) ) {
+				acc[ key ] = [];
+			} else {
+				acc[ key ] = {};
+			}
 		}
 		if ( i === normalizedPath.length - 1 ) {
 			acc[ key ] = value;

packages/block-editor/src/utils/test/object.js

@@ -150,6 +150,22 @@ describe( 'setImmutably', () => {
 			expect( result ).toEqual( { test: 2 } );
 		} );
 
+		it( 'handles first level arrays properly', () => {
+			const result = setImmutably( [ 5 ], 0, 6 );
+
+			expect( result ).toEqual( [ 6 ] );
+		} );
+
+		it( 'handles nested arrays properly', () => {
+			const result = setImmutably(
+				[ [ 'foo', [ 'bar' ] ] ],
+				[ 0, 1, 0 ],
+				'baz'
+			);
+
+			expect( result ).toEqual( [ [ 'foo', [ 'baz' ] ] ] );
+		} );
+
 		describe( 'with array notation access', () => {
 			it( 'assigns values at deeper levels', () => {
 				const result = setImmutably( {}, [ 'foo', 'bar', 'baz' ], 5 );
@@ -236,5 +252,25 @@ describe( 'setImmutably', () => {
 			expect( result.foo.bar ).not.toBe( input.foo.bar );
 			expect( result.foo.bar.baz ).not.toBe( input.foo.bar.baz );
 		} );
+
+		it( 'clones arrays at the first level', () => {
+			const input = [];
+			const result = setImmutably( input, 0, 1 );
+
+			expect( result ).not.toBe( input );
+		} );
+
+		it( 'clones arrays at deeper levels', () => {
+			const input = [ [ [ [ 'foo', [ 'bar' ] ] ] ] ];
+			const result = setImmutably( input, [ 0, 0, 0, 1, 0 ], 'baz' );
+
+			expect( result ).not.toBe( input );
+			expect( result[ 0 ] ).not.toBe( input[ 0 ] );
+			expect( result[ 0 ][ 0 ] ).not.toBe( input[ 0 ][ 0 ] );
+			expect( result[ 0 ][ 0 ][ 0 ] ).not.toBe( input[ 0 ][ 0 ][ 0 ] );
+			expect( result[ 0 ][ 0 ][ 0 ][ 1 ] ).not.toBe(
+				input[ 0 ][ 0 ][ 0 ][ 1 ]
+			);
+		} );
 	} );
 } );