Fix restoring product prices on bulk edit (#50836)

* Set the regular price when the `Change to:` price is left empty

* Avoid fatal error when price is empty

* Add changefile(s) from automation for the following project(s): woocommerce

* Add e2e test

* Fix lint errors

---------

Co-authored-by: github-actions <github-actions@github.com>

plugins/woocommerce/changelog/50836-29617-fix-bulk-edit-price

@@ -0,0 +1,4 @@
+Significance: minor
+Type: fix
+
+Product bulk edit: allow to restore original price and avoid fatal errors.

plugins/woocommerce/includes/admin/class-wc-admin-post-types.php

@@ -906,13 +906,17 @@ class WC_Admin_Post_Types {
 
 		switch ( $change_price ) {
 			case 1:
-				$new_price = $price;
+				if ( empty( $price ) ) {
+					$new_price = $product->get_regular_price();
+				} else {
+					$new_price = $price;
+				}
 				break;
 			case 2:
 				if ( $is_percentage ) {
 					$percent   = $price / 100;
 					$new_price = $old_price + ( $old_price * $percent );
-				} else {
+				} elseif ( ! empty( $price ) ) {
 					$new_price = $old_price + $price;
 				}
 				break;
@@ -920,7 +924,7 @@ class WC_Admin_Post_Types {
 				if ( $is_percentage ) {
 					$percent   = $price / 100;
 					$new_price = max( 0, $old_price - ( $old_price * $percent ) );
-				} else {
+				} elseif ( ! empty( $price ) ) {
 					$new_price = max( 0, $old_price - $price );
 				}
 				break;

plugins/woocommerce/tests/e2e-pw/tests/merchant/product-edit.spec.js

@@ -185,3 +185,100 @@ test(
 		} );
 	}
 );
+
+test(
+	'can restore regular price when bulk editing products',
+	{ tag: [ '@gutenberg', '@services' ] },
+	async ( { page, products } ) => {
+		await page.goto( `wp-admin/edit.php?post_type=product` );
+
+		const salePriceDecrease = 10;
+
+		await test.step( 'select and bulk edit the products', async () => {
+			for ( const product of products ) {
+				await page.getByLabel( `Select ${ product.name }` ).click();
+			}
+
+			await page
+				.locator( '#bulk-action-selector-top' )
+				.selectOption( 'Edit' );
+			await page.locator( '#doaction' ).click();
+
+			await expect(
+				await page.locator( '#bulk-titles-list li' ).count()
+			).toEqual( products.length );
+		} );
+
+		await test.step( 'update the sale price', async () => {
+			await page
+				.locator( 'select[name="change_sale_price"]' )
+				.selectOption(
+					'Set to regular price decreased by (fixed amount or %):'
+				);
+			await page
+				.getByPlaceholder( 'Enter sale price ($)' )
+				.fill( `${ salePriceDecrease }%` );
+		} );
+
+		await test.step( 'save the updates', async () => {
+			await page.getByRole( 'button', { name: 'Update' } ).click();
+		} );
+
+		await test.step( 'verify the changes', async () => {
+			for ( const product of products ) {
+				await page.goto( `product/${ product.slug }` );
+
+				const expectedRegularPrice = product.regular_price;
+
+				const expectedSalePrice = (
+					expectedRegularPrice *
+					( 1 - salePriceDecrease / 100 )
+				).toFixed( 2 );
+
+				await expect
+					.soft(
+						await page
+							.locator( 'ins' )
+							.getByText( `$${ expectedSalePrice }` )
+							.count()
+					)
+					.toBeGreaterThan( 0 );
+			}
+		} );
+
+		await test.step( 'Update products leaving the "Sale > Change to" empty', async () => {
+			await page.goto( `wp-admin/edit.php?post_type=product` );
+
+			for ( const product of products ) {
+				await page.getByLabel( `Select ${ product.name }` ).click();
+			}
+
+			await page
+				.locator( '#bulk-action-selector-top' )
+				.selectOption( 'Edit' );
+			await page.locator( '#doaction' ).click();
+
+			await page
+				.locator( 'select[name="change_sale_price"]' )
+				.selectOption( 'Change to:' );
+
+			await page.getByRole( 'button', { name: 'Update' } ).click();
+		} );
+
+		await test.step( 'Verify products have their regular price again', async () => {
+			for ( const product of products ) {
+				await page.goto( `product/${ product.slug }` );
+
+				const expectedRegularPrice = product.regular_price;
+
+				await expect
+					.soft( await page.locator( 'ins' ).count() )
+					.toBe( 0 );
+
+				await expect
+					.soft( await page.locator( 'bdi' ).first() )
+					.toContainText( expectedRegularPrice );
+			}
+		} );
+	}
+);