phantomknight287/saturn

public

The operating system for your freelance business.

Feature/sat 27 fix send to client option (#35)6d609615 months ago31 lines · 653 B

1	# Interface Design for Testability
2
3	Good interfaces make testing natural:
4
5	1. Accept dependencies, don't create them
6
7	```typescript
8	// Testable
9	function processOrder(order
10
11	// Hard to test
12	function processOrder(order
13	const gateway =
14	}
15	```
16
17	2. Return results, don't produce side effects
18
19	```typescript
20	// Testable
21	function calculateDiscount(cart
22
23	// Hard to test
24	function applyDiscount(cart
25	cart.total -=
26	}
27	```
28
29	3. Small surface area
30	- Fewer methods = fewer tests needed
31	- Fewer params = simpler test setup

,

paymentGateway

)

{}

)

{

new

StripeGateway

()

;

)

:

Discount

{}

)

:

void

{

discount

;