fix: only highest eligible coupon applied (#38416)

fix: only highest eligible coupon applied (#38416)

* fix: application of pricing rule when coupon is used

(cherry picked from commit d34787c)

Co-authored-by: sandratridz <102575830+sandratridz@users.noreply.github.com>

erpnext/accounts/doctype/pricing_rule/utils.py

@@ -581,6 +581,8 @@ def apply_pricing_rule_on_transaction(doc):
 			if d.price_or_product_discount == "Price":
 				if d.apply_discount_on:
 					doc.set("apply_discount_on", d.apply_discount_on)
+				# Variable to track whether the condition has been met
+				condition_met = False
 
 				for field in ["additional_discount_percentage", "discount_amount"]:
 					pr_field = "discount_percentage" if field == "additional_discount_percentage" else field
@@ -603,6 +605,11 @@ def apply_pricing_rule_on_transaction(doc):
 							if coupon_code_pricing_rule == d.name:
 								# if selected coupon code is linked with pricing rule
 								doc.set(field, d.get(pr_field))
+
+								# Set the condition_met variable to True and break out of the loop
+								condition_met = True
+								break
+
 							else:
 								# reset discount if not linked
 								doc.set(field, 0)
@@ -611,6 +618,10 @@ def apply_pricing_rule_on_transaction(doc):
 							doc.set(field, 0)
 
 				doc.calculate_taxes_and_totals()
+
+				# Break out of the main loop if the condition is met
+				if condition_met:
+					break
 			elif d.price_or_product_discount == "Product":
 				item_details = frappe._dict({"parenttype": doc.doctype, "free_item_data": []})
 				get_product_discount_rule(d, item_details, doc=doc)