adding ranged number type, for use in stats (#581)

d2common/d2math/ranged_number.go

@@ -0,0 +1,101 @@
+package d2math
+
+import "fmt"
+
+// RangedNumber is a number with a min and max range
+type RangedNumber struct {
+	min int
+	max int
+}
+
+// Min returns the min value, swapping min/max if not ordered
+func (rn *RangedNumber) Min() int {
+	if rn.min > rn.max {
+		rn.Set(rn.max, rn.min)
+	}
+
+	return rn.min
+}
+
+// Max returns the max value, swapping min/max if not ordered
+func (rn *RangedNumber) Max() int {
+	if rn.min > rn.max {
+		rn.Set(rn.max, rn.min)
+	}
+
+	return rn.max
+}
+
+// Set sets the min and max values, ordering the arguments if necessary
+func (rn *RangedNumber) Set(min, max int) *RangedNumber {
+	rn.SetMin(min)
+	rn.SetMax(max)
+
+	return rn
+}
+
+// SetMin sets the minimum value
+func (rn *RangedNumber) SetMin(min int) *RangedNumber {
+	rn.min = min
+	if rn.min > rn.max {
+		rn.min = rn.max
+		rn.max = min
+	}
+
+	return rn
+}
+
+// SetMax sets the maximum value
+func (rn *RangedNumber) SetMax(max int) *RangedNumber {
+	rn.max = max
+	if rn.min > rn.max {
+		rn.max = rn.min
+		rn.min = max
+	}
+
+	return rn
+}
+
+// Clone creates a new copy of a ranged number, with the same min/max
+func (rn RangedNumber) Clone() *RangedNumber {
+	return &rn
+}
+
+// Copy copies the min/max values of the given ranged number
+func (rn *RangedNumber) Copy(other *RangedNumber) *RangedNumber {
+	return rn.Set(other.min, other.max)
+}
+
+// Equals checks equality with the given ranged number
+func (rn *RangedNumber) Equals(other *RangedNumber) bool {
+	return rn.min == other.min && rn.max == other.max
+}
+
+// Add adds the given ranged number to this one, returning this one
+func (rn *RangedNumber) Add(other *RangedNumber) *RangedNumber {
+	return rn.Set(rn.min+other.min, rn.max+other.max)
+}
+
+// Sub subtracts the given ranged number from this one, returning this one
+func (rn *RangedNumber) Sub(other *RangedNumber) *RangedNumber {
+	return rn.Set(rn.min - other.min, rn.max - other.max)
+}
+
+// Mul multiplies this ranged number by the given ranged number, returning this one
+func (rn *RangedNumber) Mul(other *RangedNumber) *RangedNumber {
+	return rn.Set(rn.min * other.min, rn.max * other.max)
+}
+
+// Div divides this ranged number by the given ranged number, returning this one
+func (rn *RangedNumber) Div(other *RangedNumber) *RangedNumber {
+	return rn.Set(rn.min / other.min, rn.max / other.max)
+}
+
+func (rn *RangedNumber) String() string {
+	if rn.Min() == rn.Max() { // ensures ordering
+		return fmt.Sprintf("%d", rn.min)
+	}
+
+	return fmt.Sprintf("%d to %d", rn.min, rn.max)
+}
+

d2common/d2math/ranged_number_test.go

@@ -0,0 +1,117 @@
+package d2math
+
+import "testing"
+
+func TestRangedNumber_Clone(t *testing.T) {
+	rn1 := &RangedNumber{1, 1}
+	rn2 := rn1.Clone()
+
+	if &rn1 == &rn2 {
+		t.Errorf("Cloned ranged number is not unique: *%d == *%d", &rn1, &rn2)
+	}
+}
+
+func TestRangedNumber_Copy(t *testing.T) {
+	rn1 := &RangedNumber{1, 1}
+	rn2 := rn1.Clone().Set(-1, -1)
+	rn1.Copy(rn2)
+
+	if rn1.Min() != rn2.Min() || rn1.Max() != rn2.Max() {
+		t.Errorf("Min/Max values were not copied: %d != %d", rn1, rn2)
+	}
+}
+
+func TestRangedNumber_Set(t *testing.T) {
+	badMin, badMax := 10, -10
+	rn := &RangedNumber{badMin, badMax} // should get swapped when used
+
+	if rn.Min() == badMin || rn.Max() == badMax {
+		t.Errorf("Min/Max values were not ordered: %d", rn)
+	}
+
+	rn.Set(badMin, badMax)
+
+	if rn.Min() == badMin || rn.Max() == badMax {
+		t.Errorf("Min/Max values were not ordered: %d", rn)
+	}
+}
+
+func TestRangedNumber_Equals(t *testing.T) {
+	min, max := 1, 2
+	rn1 := &RangedNumber{min, max}
+	rn2 := rn1.Clone()
+
+	if !rn1.Equals(rn2) {
+		t.Errorf("Not equal when they should be: %d == %d", rn1, rn2)
+	}
+
+	rn1.Set(3, 4)
+
+	if rn1.Equals(rn2) {
+		t.Errorf("equal when they should NOT be: %d != %d", rn1, rn2)
+	}
+}
+
+func TestRangedNumber_Add(t *testing.T) {
+	min, max := 1, 2
+	rn1 := &RangedNumber{min, max}
+	rn2 := rn1.Clone()
+
+	rn1.Add(rn2)
+
+	if rn1.Min() != 2 || rn1.Max() != 4 {
+		t.Errorf("Unexpected value after addition: %d ", rn1)
+	}
+}
+
+func TestRangedNumber_Sub(t *testing.T) {
+	min, max := 1, 2
+	rn1 := &RangedNumber{min, max}
+	rn2 := rn1.Clone()
+
+	rn1.Sub(rn2)
+
+	if rn1.Min() != 0 || rn1.Max() != 0 {
+		t.Errorf("Unexpected value after subtraction: %d ", rn1)
+	}
+}
+
+func TestRangedNumber_Mul(t *testing.T) {
+	min, max := 1, 2
+	rn1 := &RangedNumber{min, max}
+	rn2 := rn1.Clone()
+
+	rn1.Mul(rn2)
+
+	if rn1.Min() != 1 || rn1.Max() != 4 {
+		t.Errorf("Unexpected value after multiplication: %d ", rn1)
+	}
+}
+
+func TestRangedNumber_Div(t *testing.T) {
+	min, max := 1, 2
+	rn1 := &RangedNumber{min, max}
+	rn2 := rn1.Clone()
+
+	rn1.Div(rn2)
+
+	if rn1.Min() != 1 || rn1.Max() != 1 {
+		t.Errorf("Unexpected value after division: %d ", rn1)
+	}
+}
+
+func TestRangedNumber_String(t *testing.T) {
+	rn := &RangedNumber{}
+
+	if rn.String() != "0" {
+		t.Errorf("Unexpected string output: %d ", rn)
+	}
+
+	if rn.Set(0, -1).String() != "-1 to 0" {
+		t.Errorf("Unexpected string output: %d ", rn)
+	}
+
+	if rn.Set(-10, 20).String() != "-10 to 20" {
+		t.Errorf("Unexpected string output: %d ", rn)
+	}
+}