State Transition Testing

Learning objectives#

• Draw a state transition diagram
• Build a state table
• Test valid and invalid transitions
• Apply it to workflows

Explanation#

A state is a condition the system is in (Pending, Paid, Shipped). An event triggers a transition to another state.

Test every valid transition, and also invalid ones — the system should refuse them gracefully.

Typical uses: order workflows, account lockouts, approval processes, subscription status.

Code example: Order status workflow#

1            pay              ship              deliver
2Pending ─────────► Paid ─────────► Shipped ─────────► Delivered
3   │ cancel           │ cancel (refund)
4   ▼                  ▼
5Cancelled ◄───────────┘
6

7Valid transitions to test: Pending→Paid, Paid→Shipped, Shipped→Delivered,
8                            Pending→Cancelled, Paid→Cancelled (refund issued)
9Invalid transitions to test: Delivered→Cancelled, Cancelled→Shipped, Pending→Shipped

Five valid and three invalid transition tests cover the workflow’s rules.

This example is illustrative. Copy or download it and run it in your own environment; the expected output is shown above.

Step-by-step explanation#

1. Identify states and events from the requirements.
2. Draw transitions between states.
3. Test every valid transition.
4. Attempt invalid ones and expect a clear refusal.

Real-world use case#

Common mistakes#

Best practices#

• Draw the diagram first
• Cover every transition at least once
• Test invalid transitions
• Verify side effects

Remember this#

Practice exercise#

1Start → 1st wrong → 2nd wrong → Blocked; a correct PIN from any non-blocked state → Access granted.

Mini quiz#

Want more? Practise all Manual Testing MCQs · Manual Testing interview questions

Related topics#

My notes#

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