test cases for One Rupee Coin Box

1). How do we write test cases without documents or knowing the requirements?

We can go to adopt a testing technique called Exploratory Testing. According to James Bach exploratory testing is defined as "an interactive process of concurrent product exploration, test design, and test execution."

2). what are the test cases for one Rupees Coin Box (Telephone box)?

Positive test cases:

TC1: Pick up the Handset

Expected: Should display the message " Insert one rupee coin" 

TC2: Insert the coin 

Expected: Should display the message " Dial the Number" 

TC3: When you get a busy tone, hang-up the receiver

Expected: The inserted one rupee coin comes out of the exit door.

TC4: Finish off the conversation and hang-up the receiver

Expected: The inserted coin should not come out.

TC5: During the conversation, in case of a local call, (assume the duration is of 60 sec), when 45 as are completed

Expected: It should prompt you to insert another coin to continue by giving beeps.

TC6: In the above scenario, if another coin is inserted

Expected: 60 sec will be added to the counter.

TC7: In the TC5 scenario, if you don't insert one more coin.

Expected: The call gets ended.

TC8: Pick up the receiver. Insert appropriate one rupee coin; Dial the number after hearing the ring tone. Assume it got connected and you are getting the ring tone. Immediately you end up the call.

Expected: The inserted one rupee coin comes out of the exit door.