write unit tests for decimal64.go

decimal64.go

@@ -274,7 +274,7 @@ func (d Decimal64) parts() (fl flavor, sign int, exp int, significand uint64) {
 
 // decParts gets the parts and returns in decParts stuct, doesn't get the magnitude due to performance issues\
 // TODO: rename this to parts when parts is depreciated
-func (d *Decimal64) getParts() decParts {
+func (d Decimal64) getParts() decParts {
 	var fl flavor
 	var sign, exp int
 	var significand uint64
@@ -306,7 +306,7 @@ func (d *Decimal64) getParts() decParts {
 			exp = 0
 		}
 	}
-	return decParts{fl, sign, exp, uint128T{significand, 0}, 0, d}
+	return decParts{fl, sign, exp, uint128T{significand, 0}, 0, &d}
 }
 
 func expWholeFrac(exp int, significand uint64) (exp2 int, whole uint64, frac uint64) {
@@ -438,7 +438,7 @@ func (d Decimal64) IsSubnormal() bool {
 }
 
 func (dec *decParts) isZero() bool {
-	return dec.significand.lo == 0 && dec.significand.hi == 0 && dec.fl == flNormal
+	return dec.significand.lo == 0 &&  dec.significand.hi == 0 && dec.fl == flNormal
 }
 
 func (dec *decParts) isInf() bool {

decimal64_test.go

@@ -89,6 +89,12 @@ func TestDecimal64IsInf(t *testing.T) {
 	require.False(t, SNaN64.IsInf())
 	require.False(t, NewDecimal64FromInt64(42).IsInf())
 	require.False(t, NewDecimal64FromInt64(-42).IsInf())
+
+	a := Infinity64.getParts()
+	require.True(t, a.isInf())
+
+	b := NegInfinity64.getParts()
+	require.True(t, b.isInf())
 }
 
 func TestDecimal64IsNaN(t *testing.T) {
@@ -169,7 +175,26 @@ func TestNumDecimalDigits(t *testing.T) {
 
 func TestIsNaN(t *testing.T) {
 	require := require.New(t)
-	require.Equal(false, Zero64.getParts().isNaN())
-	require.Equal(true, SNaN64.getParts().isNaN())
-	require.Equal(true, QNaN64.getParts().isNaN())
+	a := Zero64.getParts()
+	require.Equal(false, a.isNaN())
+
+	b := SNaN64.getParts()
+	require.Equal(true, b.isSNaN())
+
+	c := QNaN64.getParts()
+	require.Equal(true, c.isQNaN())
 }
+
+func TestIsSubnormal(t *testing.T) {
+	require := require.New(t)
+
+	require.Equal(true, MustParseDecimal64("0.1E-383").IsSubnormal())
+	require.Equal(true, MustParseDecimal64("-0.1E-383").IsSubnormal())
+	require.Equal(false, MustParseDecimal64("NaN10").IsSubnormal())
+	subnormal64Parts := MustParseDecimal64("0.1E-383").getParts()
+	require.Equal(true, subnormal64Parts.isSubnormal())
+
+	require.Equal(false, NewDecimal64FromInt64(42).IsSubnormal())
+	fortyTwoParts := NewDecimal64FromInt64(42).getParts()
+	require.Equal(false, fortyTwoParts.isSubnormal())
+}