Preserve input type.

common/math/math.go

@@ -26,29 +26,32 @@ func DoArithmetic(a, b any, op rune) (any, error) {
 	var ai, bi int64
 	var af, bf float64
 	var au, bu uint64
+	var isInt, isFloat, isUint bool
 	switch av.Kind() {
 	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
 		ai = av.Int()
 		switch bv.Kind() {
 		case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+			isInt = true
 			bi = bv.Int()
 		case reflect.Float32, reflect.Float64:
+			isFloat = true
 			af = float64(ai) // may overflow
-			ai = 0
 			bf = bv.Float()
 		case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
 			bu = bv.Uint()
 			if ai >= 0 {
+				isUint = true
 				au = uint64(ai)
-				ai = 0
 			} else {
+				isInt = true
 				bi = int64(bu) // may overflow
-				bu = 0
 			}
 		default:
 			return nil, errors.New("can't apply the operator to the values")
 		}
 	case reflect.Float32, reflect.Float64:
+		isFloat = true
 		af = av.Float()
 		switch bv.Kind() {
 		case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
@@ -66,17 +69,18 @@ func DoArithmetic(a, b any, op rune) (any, error) {
 		case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
 			bi = bv.Int()
 			if bi >= 0 {
+				isUint = true
 				bu = uint64(bi)
-				bi = 0
 			} else {
+				isInt = true
 				ai = int64(au) // may overflow
-				au = 0
 			}
 		case reflect.Float32, reflect.Float64:
+			isFloat = true
 			af = float64(au) // may overflow
-			au = 0
 			bf = bv.Float()
 		case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
+			isUint = true
 			bu = bv.Uint()
 		default:
 			return nil, errors.New("can't apply the operator to the values")
@@ -94,38 +98,32 @@ func DoArithmetic(a, b any, op rune) (any, error) {
 
 	switch op {
 	case '+':
-		if ai != 0 || bi != 0 {
+		if isInt {
 			return ai + bi, nil
-		} else if af != 0 || bf != 0 {
+		} else if isFloat {
 			return af + bf, nil
-		} else if au != 0 || bu != 0 {
+		}
 		return au + bu, nil
-		}
-		return 0, nil
 	case '-':
-		if ai != 0 || bi != 0 {
+		if isInt {
 			return ai - bi, nil
-		} else if af != 0 || bf != 0 {
+		} else if isFloat {
 			return af - bf, nil
-		} else if au != 0 || bu != 0 {
+		}
 		return au - bu, nil
-		}
-		return 0, nil
 	case '*':
-		if ai != 0 || bi != 0 {
+		if isInt {
 			return ai * bi, nil
-		} else if af != 0 || bf != 0 {
+		} else if isFloat {
 			return af * bf, nil
-		} else if au != 0 || bu != 0 {
-			return au * bu, nil
 		}
-		return 0, nil
+		return au * bu, nil
 	case '/':
-		if bi != 0 {
+		if isInt && bi != 0 {
 			return ai / bi, nil
-		} else if bf != 0 {
+		} else if isFloat && bf != 0 {
 			return af / bf, nil
-		} else if bu != 0 {
+		} else if isUint && bu != 0 {
 			return au / bu, nil
 		}
 		return nil, errors.New("can't divide the value by 0")

common/math/math_test.go

@@ -30,10 +30,12 @@ func TestDoArithmetic(t *testing.T) {
 		expect any
 	}{
 		{3, 2, '+', int64(5)},
+		{0, 0, '+', int64(0)},
 		{3, 2, '-', int64(1)},
 		{3, 2, '*', int64(6)},
 		{3, 2, '/', int64(1)},
 		{3.0, 2, '+', float64(5)},
+		{0.0, 0, '+', float64(0.0)},
 		{3.0, 2, '-', float64(1)},
 		{3.0, 2, '*', float64(6)},
 		{3.0, 2, '/', float64(1.5)},
@@ -42,18 +44,22 @@ func TestDoArithmetic(t *testing.T) {
 		{3, 2.0, '*', float64(6)},
 		{3, 2.0, '/', float64(1.5)},
 		{3.0, 2.0, '+', float64(5)},
+		{0.0, 0.0, '+', float64(0.0)},
 		{3.0, 2.0, '-', float64(1)},
 		{3.0, 2.0, '*', float64(6)},
 		{3.0, 2.0, '/', float64(1.5)},
 		{uint(3), uint(2), '+', uint64(5)},
+		{uint(0), uint(0), '+', uint64(0)},
 		{uint(3), uint(2), '-', uint64(1)},
 		{uint(3), uint(2), '*', uint64(6)},
 		{uint(3), uint(2), '/', uint64(1)},
 		{uint(3), 2, '+', uint64(5)},
+		{uint(0), 0, '+', uint64(0)},
 		{uint(3), 2, '-', uint64(1)},
 		{uint(3), 2, '*', uint64(6)},
 		{uint(3), 2, '/', uint64(1)},
 		{3, uint(2), '+', uint64(5)},
+		{0, uint(0), '+', uint64(0)},
 		{3, uint(2), '-', uint64(1)},
 		{3, uint(2), '*', uint64(6)},
 		{3, uint(2), '/', uint64(1)},
@@ -66,16 +72,15 @@ func TestDoArithmetic(t *testing.T) {
 		{-3, uint(2), '*', int64(-6)},
 		{-3, uint(2), '/', int64(-1)},
 		{uint(3), 2.0, '+', float64(5)},
+		{uint(0), 0.0, '+', float64(0)},
 		{uint(3), 2.0, '-', float64(1)},
 		{uint(3), 2.0, '*', float64(6)},
 		{uint(3), 2.0, '/', float64(1.5)},
 		{3.0, uint(2), '+', float64(5)},
+		{0.0, uint(0), '+', float64(0)},
 		{3.0, uint(2), '-', float64(1)},
 		{3.0, uint(2), '*', float64(6)},
 		{3.0, uint(2), '/', float64(1.5)},
-		{0, 0, '+', 0},
-		{0, 0, '-', 0},
-		{0, 0, '*', 0},
 		{"foo", "bar", '+', "foobar"},
 		{3, 0, '/', false},
 		{3.0, 0, '/', false},