func TestDecGobEncoding(t *testing.T) {
var medium bytes.Buffer
enc := gob.NewEncoder(&medium)
dec := gob.NewDecoder(&medium)
for i, test := range decGobEncodingTests {
for j := 0; j < 2; j++ {
for k := inf.Scale(-5); k <= 5; k++ {
medium.Reset() // empty buffer for each test case (in case of failures)
stest := test
if j != 0 {
// negative numbers
stest = "-" + test
}
var tx inf.Dec
tx.SetString(stest)
tx.SetScale(k) // test with positive, negative, and zero scale
if err := enc.Encode(&tx); err != nil {
t.Errorf("#%d%c: encoding failed: %s", i, 'a'+j, err)
}
var rx inf.Dec
if err := dec.Decode(&rx); err != nil {
t.Errorf("#%d%c: decoding failed: %s", i, 'a'+j, err)
}
if rx.Cmp(&tx) != 0 {
t.Errorf("#%d%c: transmission failed: got %s want %s", i, 'a'+j, &rx, &tx)
}
}
}
}
}
// ParseQuantity turns str into a Quantity, or returns an error.
func ParseQuantity(str string) (*Quantity, error) {
parts := splitRE.FindStringSubmatch(strings.TrimSpace(str))
// regexp returns are entire match, followed by an entry for each () section.
if len(parts) != 3 {
return nil, ErrFormatWrong
}
amount := new(inf.Dec)
if _, ok := amount.SetString(parts[1]); !ok {
return nil, ErrNumeric
}
base, exponent, format, ok := quantitySuffixer.interpret(suffix(parts[2]))
if !ok {
return nil, ErrSuffix
}
// So that no one but us has to think about suffixes, remove it.
if base == 10 {
amount.SetScale(amount.Scale() + inf.Scale(-exponent))
} else if base == 2 {
// numericSuffix = 2 ** exponent
numericSuffix := big.NewInt(1).Lsh(bigOne, uint(exponent))
ub := amount.UnscaledBig()
amount.SetUnscaledBig(ub.Mul(ub, numericSuffix))
}
// Cap at min/max bounds.
sign := amount.Sign()
if sign == -1 {
amount.Neg(amount)
}
// This rounds non-zero values up to the minimum representable
// value, under the theory that if you want some resources, you
// should get some resources, even if you asked for way too small
// of an amount.
// Arguably, this should be inf.RoundHalfUp (normal rounding), but
// that would have the side effect of rounding values < .5m to zero.
amount.Round(amount, 3, inf.RoundUp)
// The max is just a simple cap.
if amount.Cmp(maxAllowed) > 0 {
amount.Set(maxAllowed)
}
if format == BinarySI && amount.Cmp(decOne) < 0 && amount.Cmp(decZero) > 0 {
// This avoids rounding and hopefully confusion, too.
format = DecimalSI
}
if sign == -1 {
amount.Neg(amount)
}
return &Quantity{amount, format}, nil
}
func TestDecSetString(t *testing.T) {
tmp := new(inf.Dec)
for i, test := range decStringTests {
if test.scale < 0 {
// SetString only supports scale >= 0
continue
}
// initialize to a non-zero value so that issues with parsing
// 0 are detected
tmp.Set(inf.NewDec(1234567890, 123))
n1, ok1 := new(inf.Dec).SetString(test.in)
n2, ok2 := tmp.SetString(test.in)
expected := inf.NewDec(test.val, test.scale)
if ok1 != test.ok || ok2 != test.ok {
t.Errorf("#%d (input '%s') ok incorrect (should be %t)", i, test.in, test.ok)
continue
}
if !ok1 {
if n1 != nil {
t.Errorf("#%d (input '%s') n1 != nil", i, test.in)
}
continue
}
if !ok2 {
if n2 != nil {
t.Errorf("#%d (input '%s') n2 != nil", i, test.in)
}
continue
}
if n1.Cmp(expected) != 0 {
t.Errorf("#%d (input '%s') got: %s want: %d", i, test.in, n1, test.val)
}
if n2.Cmp(expected) != 0 {
t.Errorf("#%d (input '%s') got: %s want: %d", i, test.in, n2, test.val)
}
}
}
func ExampleDec_SetString() {
d := new(inf.Dec)
d.SetString("012345.67890") // decimal; leading 0 ignored; trailing 0 kept
fmt.Println(d)
// Output: 12345.67890
}