Test cases for a shopping cart in an e-commerce app

1. Open the product page of an in-stock item
2. Tap Add to cart
3. Open the cart from the cart icon

Expected: The cart icon shows 1 and the cart lists the item with its image, name, variant, price and quantity 1. The subtotal equals the item price.

1. Add an item priced at ₹499 to the cart
2. Tap + twice on the cart line
3. Tap − once

Expected: The quantity reads 3 and then 2, and the line total and subtotal show ₹1,497 and then ₹998 without a full page reload.

1. Add two different items to the cart
2. Tap Remove on the first item and confirm
3. Check the subtotal and the cart icon count

Expected: Only the first item is removed, the subtotal drops by exactly its line total and the cart icon count goes down by one.

1. Open a T-shirt product page
2. Select size M in blue and tap Add to cart
3. Select size L in black and tap Add to cart
4. Open the cart

Expected: The cart shows two separate lines, each with its own size, colour, image and price. Neither variant overwrites the other.

1. Add items above the coupon's minimum cart value
2. Tap Apply coupon and enter the valid test code
3. Tap Apply

Expected: A success message names the coupon, a discount line appears and the total drops by exactly the stated discount.

1. Add two items to the cart
2. Tap Save for later on one item
3. Open the Saved for later list and tap Move to cart

Expected: While saved, the item is left out of the subtotal and the cart count. After moving back, it returns with the same variant.

1. Open a cart with two items
2. Tap Check delivery and enter a serviceable six-digit PIN code
3. Tap Check

Expected: Each item shows a delivery date or date range for that PIN code, and the PIN code is still shown when you come back to the cart.

1. Log in on phone A and add three items with different variants
2. Log in with the same account on phone B or a desktop browser
3. Open the cart on the second device

Expected: The second device shows the same three items with the same variants, quantities and subtotal.

1. Log in, add item A in size M, then log out
2. As a guest, add item A in size M and item B
3. Log in with the same account and open the cart

Expected: The cart shows item A size M once, with quantities combined by the app's rule and capped at stock, plus item B. No guest item is lost.

1. Open a product whose size L is out of stock
2. Tap size L

Expected: Size L is marked unavailable and Add to cart is disabled or replaced by Notify me. Nothing is added to the cart.

1. Add an item that has a configured maximum quantity per order
2. Tap + until the limit is reached
3. Tap + once more

Expected: The quantity stops at the limit and a message states the maximum allowed. The subtotal does not change on the extra tap.

1. Add an item with only 3 units in stock
2. Type 10 in the quantity field and confirm
3. Clear the field, or type 0, and confirm

Expected: 10 is capped at 3 with a message about limited stock. Zero or blank either asks to remove the item or restores 1, and no line ever shows quantity 0.

1. Add items to the cart
2. Enter the expired test coupon and tap Apply

Expected: An inline message says the coupon has expired. No discount line appears and the total is unchanged.

1. Apply a coupon that needs a minimum cart value
2. Remove or reduce items until the subtotal is below that minimum

Expected: The discount is removed straight away with a message showing how much more to add. The total is recalculated without the discount.

1. Tap Check delivery
2. Enter 12345, then 000000, then paste text containing letters
3. Enter a valid but non-serviceable PIN code

Expected: Five digits, 000000 and letters are rejected with a format message. The non-serviceable code marks each affected item as not deliverable to that PIN code.

1. Set a PIN code where one cart item cannot be delivered
2. Tap Proceed to checkout

Expected: The app flags the undeliverable item and offers to remove it or save it for later. Checkout does not start with that item silently included.

1. Add an item and note its price
2. Raise its price in the test admin panel, or wait for a sale price to end
3. Reopen the cart

Expected: The cart shows the new price with a notice such as Price increased by ₹50, and the subtotal uses the new price.

1. On account A, add the last unit of an item to the cart
2. On account B, buy that unit
3. Reopen account A's cart

Expected: The item is marked Out of stock and left out of the subtotal. Proceed to checkout asks to remove it or moves it to Save for later.

1. Apply a test coupon that expires within the hour
2. Close the app and reopen it after the expiry time
3. Open the cart

Expected: The coupon is shown as expired and removed, and the total returns to the undiscounted amount before checkout.

1. Add the red variant of a product to the cart
2. Delist the red variant in the test admin panel
3. Reopen the cart

Expected: The line shows the variant as unavailable with options to pick another colour or remove it. It is never silently swapped for another variant.

1. Log in with the same account on two phones
2. Add the same variant on both phones within a few seconds
3. Refresh the cart on both phones

Expected: Both phones show a single line whose quantity follows the app's rule and stays within the quantity limit. The totals match on both.

1. Stand near the edge of two PIN code areas
2. Tap Use my location in Check delivery and allow location access
3. Compare the detected PIN code with your postal PIN code

Expected: The app shows the detected PIN code and lets you edit it before checking. A wrong guess can be corrected without leaving the cart.

Why a real phone: Needs a real GPS fix; accuracy near PIN code boundaries cannot be mocked meaningfully.

1. Set the phone's time zone to US Pacific
2. Check delivery for a serviceable PIN code late in the evening, IST
3. Compare the date shown with a phone set to IST

Expected: Both phones show the same delivery date. The estimate does not shift by a day because of the phone's time zone.

1. Switch the phone to 2G, or stand where the signal is weak
2. Tap Add to cart once, then again quickly
3. Open the cart once the request completes

Expected: The button shows a loading state and ignores the second tap. The cart holds exactly one unit, or shows a retry message if the add failed.

Why a real phone: Real carrier latency and packet loss expose double adds that uniform emulator throttling misses.

1. Open the cart on Wi-Fi
2. Tap + on an item and immediately turn Wi-Fi off
3. Wait for mobile data to connect and refresh the cart

Expected: The new quantity is saved once the connection returns, or reverts with an error message. After refresh, the quantity shown matches the saved one.

Why a real phone: The Wi-Fi to Jio, Airtel or Vi data handover drops in-flight requests unpredictably.

1. Open the cart on mobile data
2. Enter a lift or an underground metro stretch
3. Remove one item and change another item's quantity
4. Return to coverage and refresh the cart

Expected: The app shows an offline or retry message instead of an endless spinner. After refresh, the cart matches what the app last confirmed, with no phantom removals.

Why a real phone: Dead zones leave requests hanging, unlike aeroplane mode, which fails them instantly.

1. On a 3–4 GB RAM phone, change an item's quantity in the cart
2. Switch to the camera and two or three heavy apps
3. Return to the shopping app from recent apps

Expected: The app reloads without losing the cart, shows the changed quantity and does not duplicate any line.

Why a real phone: Low-RAM phones kill background apps aggressively; emulators rarely reproduce this system kill.

1. On a 3–4 GB RAM phone, add 40 items with images to the cart
2. Scroll quickly from top to bottom and back
3. Change the quantity of the last item

Expected: Scrolling stays smooth without blank image tiles or the app restarting, and the last item's quantity and the subtotal update.

Why a real phone: Frame drops and memory pressure only appear on real budget hardware with slow storage.

1. On a Xiaomi, Realme or Vivo phone, turn on battery saver and close the app
2. Add an item to the same account's cart from a desktop browser
3. Open the app on the phone and check the cart

Expected: On opening, the cart and the cart icon count show the item added on desktop without a manual refresh.

Why a real phone: Each OEM Android skin restricts background data and app restarts differently.

1. Send yourself a product link in a messaging app
2. Tap the link with the shopping app installed and logged in
3. Pick a variant and tap Add to cart

Expected: The link opens the product inside the app, not a logged-out browser page, and the item lands in the logged-in account's cart.

Why a real phone: App link handling differs across OEM skins, default browsers and messaging apps' in-app browsers.

1. Leave an item in the cart with notifications allowed
2. Lower its price in the test admin panel, or wait for the reminder
3. Tap the notification when it arrives

Expected: The notification arrives and opens the cart or the product with the current price, not the home screen.

Why a real phone: Push delivery depends on OEM battery settings and whether the app was killed.

1. Log in as account A and add items, a coupon and a PIN code
2. Log out and open the cart as a guest
3. Log in as account B on the same phone and open the cart

Expected: The guest cart is empty after logout. Account B sees only its own cart, with none of account A's items, coupon or PIN code.

1. Log in and add items to the cart
2. Leave the app idle until the session timeout your app sets has passed
3. Tap Proceed to checkout

Expected: The app asks you to log in again. After login, the cart still holds the same items, variants and quantities.

1. Turn on TalkBack on Android or VoiceOver on an iPhone
2. Move focus through a cart line, its quantity stepper and Remove
3. Double-tap the increase button

Expected: The reader announces the item name, variant, price and quantity, labels buttons such as Increase quantity, and announces the new quantity.

Why a real phone: VoiceOver is not available in the iOS simulator; it needs a real iPhone.

1. Set font size and display size to the largest in phone settings
2. Open a cart with long product names and a coupon applied

Expected: Names wrap instead of overlapping, prices and the quantity stepper stay readable, and Proceed to checkout is fully visible.

1. Switch the app language to Hindi
2. Add items totalling more than ₹1,00,000, including one out-of-stock item
3. Read every label, message and amount in the cart

Expected: Labels, stock and coupon messages appear in Hindi without truncation, and amounts use Indian grouping such as ₹1,24,500.