Usage

Test data

Aspect Tested	Test	Expected Outcome	Actual Outcome
+ operator	1 3 +	(1+3)	(1+3)
- operator	1 3 -	(1-3)	(1-3)
* operator	1 3 *	(1*3)	(1*3)
/ operator	1 3 /	(1/3)	(1/3)
Infix expression with parentheses	1 2 + 3 4 + *	((1+2)*(3+4))	((1+2)*(3+4))
Expression without spaces	1 4 3*+ 2+	((1+(4*3))+2)	((1+(4*3))+2)
Invalid operator	1 2 + 3 + 4 &	Invalid token &	Invalid token &
Invalid token beginning with a digit	1a 3 +	Invalid token a	Invalid token a