Fix/newFromFloat-currency-panic (#145)

* test(New-and-NewFromFloat): added test suits with unregistered currency

* fix(NewFromFloat): no longer panics when given an invalid or unregistered currency

* test(New_WithUnregisteredCurrency): used a better test case

---------

Co-authored-by: Raymond <[email protected]>

money.go

@@ -88,9 +88,9 @@ func New(amount int64, code string) *Money {
 
 // NewFromFloat creates and returns new instance of Money from a float64.
 // Always rounding trailing decimals down.
-func NewFromFloat(amount float64, currency string) *Money {
-	currencyDecimals := math.Pow10(GetCurrency(currency).Fraction)
-	return New(int64(amount*currencyDecimals), currency)
+func NewFromFloat(amount float64, code string) *Money {
+	currencyDecimals := math.Pow10(newCurrency(code).get().Fraction)
+	return New(int64(amount*currencyDecimals), code)
 }
 
 // Currency returns the currency used by Money.

money_test.go

@@ -27,6 +27,26 @@ func TestNew(t *testing.T) {
 	}
 }
 
+func TestNew_WithUnregisteredCurrency(t *testing.T) {
+	const currencyFooCode = "FOO"
+	const expectedAmount = 100
+	const expectedDisplay = "1.00FOO"
+
+	m := New(100, currencyFooCode)
+
+	if m.amount != expectedAmount {
+		t.Errorf("Expected amount %d got %d", expectedAmount, m.amount)
+	}
+
+	if m.currency.Code != currencyFooCode {
+		t.Errorf("Expected currency code %s got %s", currencyFooCode, m.currency.Code)
+	}
+
+	if m.Display() != expectedDisplay {
+		t.Errorf("Expected display %s got %s", expectedDisplay, m.Display())
+	}
+}
+
 func TestCurrency(t *testing.T) {
 	code := "MOCK"
 	decimals := 5
@@ -672,6 +692,26 @@ func TestNewFromFloat(t *testing.T) {
 	}
 }
 
+func TestNewFromFloat_WithUnregisteredCurrency(t *testing.T) {
+	const currencyFooCode = "FOO"
+	const expectedAmount = 1234
+	const expectedDisplay = "12.34FOO"
+
+	m := NewFromFloat(12.34, currencyFooCode)
+
+	if m.amount != expectedAmount {
+		t.Errorf("Expected amount %d got %d", expectedAmount, m.amount)
+	}
+
+	if m.currency.Code != currencyFooCode {
+		t.Errorf("Expected currency code %s got %s", currencyFooCode, m.currency.Code)
+	}
+
+	if m.Display() != expectedDisplay {
+		t.Errorf("Expected display %s got %s", expectedDisplay, m.Display())
+	}
+}
+
 func TestDefaultMarshal(t *testing.T) {
 	given := New(12345, IQD)
 	expected := `{"amount":12345,"currency":"IQD"}`