fix(types): dec from string must be finite (#1590)

Co-authored-by: Ryan Christoffersen <12519942+ryanchristo@users.noreply.github.com>

types/math/dec.go

@@ -33,6 +33,7 @@ var (
 	ErrInvalidDecString   = errors.Register(mathCodespace, 1, "invalid decimal string")
 	ErrUnexpectedRounding = errors.Register(mathCodespace, 2, "unexpected rounding")
 	ErrNonIntegeral       = errors.Register(mathCodespace, 3, "value is non-integral")
+	ErrInfiniteString     = errors.Register(mathCodespace, 4, "value is infinite")
 )
 
 // In cosmos-sdk#7773, decimal128 (with 34 digits of precision) was suggested for performing
@@ -54,7 +55,13 @@ func NewDecFromString(s string) (Dec, error) {
 	if err != nil {
 		return Dec{}, ErrInvalidDecString.Wrap(err.Error())
 	}
-	return Dec{*d}, nil
+
+	d1 := Dec{*d}
+	if d1.dec.Form == apd.Infinite {
+		return d1, ErrInfiniteString.Wrapf(s)
+	}
+
+	return d1, nil
 }
 
 func NewNonNegativeDecFromString(s string) (Dec, error) {

types/math/dec_test.go

@@ -705,3 +705,9 @@ func TestToSdkInt(t *testing.T) {
 		require.Equal(t, tc.out, b.String(), "test_%d", idx)
 	}
 }
+
+func TestInfDecString(t *testing.T) {
+	_, err := NewDecFromString("iNf")
+	require.Error(t, err)
+	require.ErrorIs(t, err, ErrInfiniteString)
+}