Write code for clear. Test output...

...Test output includes test of clear (and looks fine):

$ java -ea FractionCalculatorTest
FractionTestCalculator tests verbose output:
test "Simple parsing and operation: input of '1/2 * 3/4' should give '3/8'. Actually '3/8' is output." passes.

test "Simple parsing and operation: input of '1/2 / 3/4' should give '2/3'. Actually '2/3' is output." passes.

test "Simple parsing and operation: input of ' 1/2   +  -1/4 ' should give '1/4'. Actually '1/4' is output." passes.

test "Simple parsing and operation: input of '1/2 - 3/4' should give '-1/4'. Actually '-1/4' is output." passes.

test "Whole numbers: input of '3 * 9' should give '27'. Actually '27' is output." passes.

test "Abs: input of '-3 * 2/3 aB' should give '2'. Actually '2' is output." passes.

test "Neg: input of '3/7 N' should give '-3/7'. Actually '-3/7' is output." passes.

test "Invalid input no space: input of '1/2+1/2' should produce an ERROR. Actually '
ERROR unrecognized input '1/2+1/2' cannot process this
	Resetting calculator to its initial state (no operator and 0 as value)' is output." passes.

test "Invalid input two operators : input of '1/2 + - 3/4' should produce an ERROR. Actually '
ERROR you have input two operators: + and -.
	Resetting calculator to its initial state (no operator and 0 as value)' is output." passes.

test "Entering an invalid fraction input of '1/0' should produce an ERROR. Actually '
ERROR you have specified a fraction 1/0 with a zero denominator.
	Resetting calculator to its initial state (no operator and 0 as value)' is output." passes.

test "Try to divide by zero '1/2 / 0/3' should produce an ERROR. Actually '
ERROR you cannot divide by zero.
	Resetting calculator to its initial state (no operator and 0 as value)' is output." passes.

FractionCalculatorTest: All tests pass
Write code for quit. Test output...

...Test output includes test of quit (and looks fine):

$ java -ea FractionCalculatorTest
FractionTestCalculator tests verbose output:
test "Simple parsing and operation: input of '1/2 * 3/4' should give '3/8'. Actually '3/8' is output." passes.

test "Simple parsing and operation: input of '1/2 / 3/4' should give '2/3'. Actually '2/3' is output." passes.

test "Simple parsing and operation: input of ' 1/2   +  -1/4 ' should give '1/4'. Actually '1/4' is output." passes.

test "Simple parsing and operation: input of '1/2 - 3/4' should give '-1/4'. Actually '-1/4' is output." passes.

test "Whole numbers: input of '3 * 9' should give '27'. Actually '27' is output." passes.

test "Abs: input of '-3 * 2/3 aB' should give '2'. Actually '2' is output." passes.

test "Neg: input of '3/7 N' should give '-3/7'. Actually '-3/7' is output." passes.

test "Clear: input of '1/2 - Cl  9 * 7' should give '63'. Actually '63' is output." passes.

test "Quit: input of '1/2 - quit 30 + 10' should result in quitProgram() true. " passes.

test "Invalid input no space: input of '1/2+1/2' should produce an ERROR. Actually '
ERROR unrecognized input '1/2+1/2' cannot process this
	Resetting calculator to its initial state (no operator and 0 as value)' is output." passes.

test "Invalid input two operators : input of '1/2 + - 3/4' should produce an ERROR. Actually '
ERROR you have input two operators: + and -.
	Resetting calculator to its initial state (no operator and 0 as value)' is output." passes.

test "Entering an invalid fraction input of '1/0' should produce an ERROR. Actually '
ERROR you have specified a fraction 1/0 with a zero denominator.
	Resetting calculator to its initial state (no operator and 0 as value)' is output." passes.

test "Try to divide by zero '1/2 / 0/3' should produce an ERROR. Actually '
ERROR you cannot divide by zero.
	Resetting calculator to its initial state (no operator and 0 as value)' is output." passes.

FractionCalculatorTest: All tests pass
Get rid of actually... Test output...
...is output for passed tests as it makes output clearer:

...Test output now:

$ java -ea FractionCalculatorTest
FractionTestCalculator tests verbose output:
test "Simple parsing and operation: input of '1/2 * 3/4' should give '3/8'. " passes.

test "Simple parsing and operation: input of '1/2 / 3/4' should give '2/3'. " passes.

test "Simple parsing and operation: input of ' 1/2   +  -1/4 ' should give '1/4'. " passes.

test "Simple parsing and operation: input of '1/2 - 3/4' should give '-1/4'. " passes.

test "Whole numbers: input of '3 * 9' should give '27'. " passes.

test "Abs: input of '-3 * 2/3 aB' should give '2'. " passes.

test "Neg: input of '3/7 N' should give '-3/7'. " passes.

test "Clear: input of '1/2 - Cl  9 * 7' should give '63'. " passes.

test "Quit: input of '1/2 - quit 30 + 10' should result in quitProgram() true. " passes.

test "Invalid input no space: input of '1/2+1/2' should produce an ERROR. Actually '
ERROR unrecognized input '1/2+1/2' cannot process this
	Resetting calculator to its initial state (no operator and 0 as value)' is output." passes.

test "Invalid input two operators : input of '1/2 + - 3/4' should produce an ERROR. Actually '
ERROR you have input two operators: + and -.
	Resetting calculator to its initial state (no operator and 0 as value)' is output." passes.

test "Entering an invalid fraction input of '1/0' should produce an ERROR. Actually '
ERROR you have specified a fraction 1/0 with a zero denominator.
	Resetting calculator to its initial state (no operator and 0 as value)' is output." passes.

test "Try to divide by zero '1/2 / 0/3' should produce an ERROR. Actually '
ERROR you cannot divide by zero.
	Resetting calculator to its initial state (no operator and 0 as value)' is output." passes.

FractionCalculatorTest: All tests pass
1st stab at actual calculator... Test output...
...will document sample I/O separately.

...Test output unaltered.

$ java -ea FractionCalculatorTest
FractionTestCalculator tests verbose output:
test "Simple parsing and operation: input of '1/2 * 3/4' should give '3/8'. " passes.

test "Simple parsing and operation: input of '1/2 / 3/4' should give '2/3'. " passes.

test "Simple parsing and operation: input of ' 1/2   +  -1/4 ' should give '1/4'. " passes.

test "Simple parsing and operation: input of '1/2 - 3/4' should give '-1/4'. " passes.

test "Whole numbers: input of '3 * 9' should give '27'. " passes.

test "Abs: input of '-3 * 2/3 aB' should give '2'. " passes.

test "Neg: input of '3/7 N' should give '-3/7'. " passes.

test "Clear: input of '1/2 - Cl  9 * 7' should give '63'. " passes.

test "Quit: input of '1/2 - quit 30 + 10' should result in quitProgram() true. " passes.

test "Invalid input no space: input of '1/2+1/2' should produce an ERROR. Actually '
ERROR unrecognized input '1/2+1/2' cannot process this
	Resetting calculator to its initial state (no operator and 0 as value)' is output." passes.

test "Invalid input two operators : input of '1/2 + - 3/4' should produce an ERROR. Actually '
ERROR you have input two operators: + and -.
	Resetting calculator to its initial state (no operator and 0 as value)' is output." passes.

test "Entering an invalid fraction input of '1/0' should produce an ERROR. Actually '
ERROR you have specified a fraction 1/0 with a zero denominator.
	Resetting calculator to its initial state (no operator and 0 as value)' is output." passes.

test "Try to divide by zero '1/2 / 0/3' should produce an ERROR. Actually '
ERROR you cannot divide by zero.
	Resetting calculator to its initial state (no operator and 0 as value)' is output." passes.

FractionCalculatorTest: All tests pass