Fix mini-cart per-unit price for bulk-priced lines

Bulk (quantity-break) pricing was applied only on woocommerce_before_calculate_
totals. The mini-cart template renders each line's per-unit price BEFORE its
subtotal triggers recalculation, so the per-unit line showed the non-bulk price
(e.g. $595) while the subtotal reflected the bulk price ($575 x qty). The main
cart page, which calls calculate_totals() up front, was unaffected.

Make set_cart_item_price_from_session quantity-aware: restore the price via
effective_price_qty() with the stored line quantity so the cart item already
carries the bulk per-unit price before anything renders. apply_bulk_cart_pricing
still re-applies it on every recalculation.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: mjoslyn

src/WooHooks.php

@@ -324,8 +324,14 @@ public function set_cart_item_price_from_session( $session_data, $values, $key )
 		}
 		// Recompute for the current pricing context (so switching roles via the
 		// toolbar updates cart prices on the next load) rather than restoring the
-		// price snapshotted when the item was added.
-		$new_price                 = $this->engine->effective_price( null, $session_data['data'] );
+		// price snapshotted when the item was added. Quantity-aware so the restored
+		// per-unit price already reflects a bulk break: templates that read the item
+		// price BEFORE calculate_totals runs (notably the mini-cart, which renders
+		// each line's per-unit price before its subtotal triggers recalculation)
+		// would otherwise show the non-bulk price while the subtotal shows the bulk
+		// one. apply_bulk_cart_pricing() re-applies this on every recalculation.
+		$qty                       = isset( $values['quantity'] ) ? max( 1, (int) $values['quantity'] ) : 1;
+		$new_price                 = $this->engine->effective_price_qty( null, $session_data['data'], $qty );
 		$session_data['data']->set_price( $new_price );
 		$session_data['new_price'] = $new_price;
 		return $session_data;

tests/WooHooksTest.php

@@ -113,6 +113,30 @@ public function test_bulk_cart_below_threshold_uses_the_per_unit_price() {
 		$this->assertSame( '70', (string) $this->hooks->get_price( $product->get_price(), $product ) );
 	}
 
+	public function test_session_restore_is_quantity_aware_for_bulk() {
+		// The mini-cart renders a line's per-unit price BEFORE calculate_totals runs, so
+		// the session-restored price must already reflect the quantity break — otherwise
+		// the per-unit line shows the non-bulk price while the subtotal shows the bulk one.
+		$this->set_meta(
+			10,
+			array(
+				'_pricebook_bulk_pricing' => array(
+					'dealer' => array( array( 'min_qty' => 10, 'max_qty' => 0, 'price' => '55' ) ),
+				),
+			)
+		);
+
+		// 13 units -> the bulk per-unit price (55), not the plain dealer price (70).
+		$product  = new FakeProduct( 10, 'simple' );
+		$restored = $this->hooks->set_cart_item_price_from_session( array( 'data' => $product ), array( 'quantity' => 13 ), 'key' );
+		$this->assertSame( '55', (string) $restored['data']->get_price() );
+
+		// Below the break -> the plain per-unit price.
+		$below    = new FakeProduct( 10, 'simple' );
+		$restored = $this->hooks->set_cart_item_price_from_session( array( 'data' => $below ), array( 'quantity' => 5 ), 'key' );
+		$this->assertSame( '70', (string) $restored['data']->get_price() );
+	}
+
 	/**
 	 * A minimal WC_Cart stand-in exposing the get_cart() shape apply_bulk_cart_pricing
 	 * iterates: a list of items each with a 'data' product and a 'quantity'.