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## The keypad logic is pure Nim, so it can be driven without a window:
## press keys straight into onPress and read back what the display would say.
import std/unittest
import ../examples/calculator
proc press(c: var Calc; ids: varargs[int32]): string =
for id in ids:
onPress(addr c, id)
c.display
proc fresh(): Calc = newCalc()
suite "calculator":
test "digits accumulate into one entry":
var c = fresh()
check c.press(1, 2, 3) == "123"
test "no leading zeros":
var c = fresh()
check c.press(0, 0, 5) == "5"
test "addition":
var c = fresh()
check c.press(2, IdAdd, 3, IdEquals) == "5"
test "chaining resolves the pending op as you go":
var c = fresh()
check c.press(2, IdAdd, 3, IdMul, 4) == "4" # 2+3 folded, 4 being typed
check c.press(IdEquals) == "20" # then (5)*4
test "subtraction and division":
var c = fresh()
check c.press(9, IdSub, 4, IdEquals) == "5"
c = fresh()
check c.press(8, IdDiv, 2, IdEquals) == "4"
test "division by zero errors, and only C recovers":
var c = fresh()
check c.press(1, IdDiv, 0, IdEquals) == "Error"
check c.press(5) == "Error" # other keys are ignored
check c.press(IdClear) == "0"
check c.press(7) == "7" # usable again
test "decimals":
var c = fresh()
check c.press(1, IdDot, 5, IdAdd, 2, IdDot, 2, 5, IdEquals) == "3.75"
test "a bare dot starts at zero":
var c = fresh()
check c.press(IdDot, 5) == "0.5"
test "one dot per number":
var c = fresh()
check c.press(1, IdDot, 2, IdDot, 3) == "1.23"
test "sign flips the entry, then the result":
var c = fresh()
check c.press(4, IdSign) == "-4"
check c.press(IdSign) == "4"
c = fresh()
check c.press(2, IdAdd, 3, IdEquals, IdSign) == "-5"
test "percent":
var c = fresh()
check c.press(5, 0, IdPercent) == "0.5"
test "integers do not grow a decimal point":
var c = fresh()
check c.press(6, IdDiv, 3, IdEquals) == "2"
test "backspace rubs out typed digits only":
var c = fresh()
check c.press(1, 2, 3, IdBackspace) == "12"
check c.press(IdBackspace, IdBackspace) == "0" # empty entry shows acc
c = fresh()
check c.press(2, IdAdd, 3, IdEquals) == "5"
check c.press(IdBackspace) == "5" # a result is not an entry
test "a new number replaces the result, not appends to it":
var c = fresh()
check c.press(2, IdAdd, 3, IdEquals) == "5"
check c.press(7) == "7"
suite "keyboard":
proc typed(c: var Calc; keys: varargs[string]): string =
for k in keys:
let id = keyToId(k)
if id >= 0: onPress(addr c, id)
c.display
test "digits and operators come from the characters you type":
var c = fresh()
check c.typed("1", "2", "+", "3", "Enter") == "15"
test "both spellings of an operator work":
var c = fresh()
check c.typed("8", "/", "2", "=") == "4"
c = fresh()
check c.typed("8", "\u00f7", "2", "=") == "4" # the divide sign on the key
c = fresh()
check c.typed("3", "*", "4", "=") == "12"
c = fresh()
check c.typed("3", "\u00d7", "4", "=") == "12"
test "escape and c both clear":
var c = fresh()
check c.typed("9", "Escape") == "0"
check c.typed("9", "c") == "0"
test "backspace is wired to the key":
var c = fresh()
check c.typed("1", "2", "3", "Backspace") == "12"
test "unmapped keys are ignored, not mistaken for a digit":
var c = fresh()
check keyToId("F1") == -1
check keyToId("ArrowUp") == -1
check keyToId("q") == -1
check c.typed("5", "F1", "ArrowUp", "q") == "5"
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