1 files changed, 318 insertions, 0 deletions
diff --git a/Godeps/_workspace/src/github.com/robertkrimen/otto/evaluate.go b/Godeps/_workspace/src/github.com/robertkrimen/otto/evaluate.go
new file mode 100644
index 000000000..093054cc3
--- /dev/null
+++ b/Godeps/_workspace/src/github.com/robertkrimen/otto/evaluate.go
@@ -0,0 +1,318 @@
+package otto
+
+import (
+	"fmt"
+	"math"
+	"strings"
+
+	"github.com/robertkrimen/otto/token"
+)
+
+func (self *_runtime) evaluateMultiply(left float64, right float64) Value {
+	// TODO 11.5.1
+	return Value{}
+}
+
+func (self *_runtime) evaluateDivide(left float64, right float64) Value {
+	if math.IsNaN(left) || math.IsNaN(right) {
+		return NaNValue()
+	}
+	if math.IsInf(left, 0) && math.IsInf(right, 0) {
+		return NaNValue()
+	}
+	if left == 0 && right == 0 {
+		return NaNValue()
+	}
+	if math.IsInf(left, 0) {
+		if math.Signbit(left) == math.Signbit(right) {
+			return positiveInfinityValue()
+		} else {
+			return negativeInfinityValue()
+		}
+	}
+	if math.IsInf(right, 0) {
+		if math.Signbit(left) == math.Signbit(right) {
+			return positiveZeroValue()
+		} else {
+			return negativeZeroValue()
+		}
+	}
+	if right == 0 {
+		if math.Signbit(left) == math.Signbit(right) {
+			return positiveInfinityValue()
+		} else {
+			return negativeInfinityValue()
+		}
+	}
+	return toValue_float64(left / right)
+}
+
+func (self *_runtime) evaluateModulo(left float64, right float64) Value {
+	// TODO 11.5.3
+	return Value{}
+}
+
+func (self *_runtime) calculateBinaryExpression(operator token.Token, left Value, right Value) Value {
+
+	leftValue := left.resolve()
+
+	switch operator {
+
+	// Additive
+	case token.PLUS:
+		leftValue = toPrimitive(leftValue)
+		rightValue := right.resolve()
+		rightValue = toPrimitive(rightValue)
+
+		if leftValue.IsString() || rightValue.IsString() {
+			return toValue_string(strings.Join([]string{leftValue.string(), rightValue.string()}, ""))
+		} else {
+			return toValue_float64(leftValue.float64() + rightValue.float64())
+		}
+	case token.MINUS:
+		rightValue := right.resolve()
+		return toValue_float64(leftValue.float64() - rightValue.float64())
+
+		// Multiplicative
+	case token.MULTIPLY:
+		rightValue := right.resolve()
+		return toValue_float64(leftValue.float64() * rightValue.float64())
+	case token.SLASH:
+		rightValue := right.resolve()
+		return self.evaluateDivide(leftValue.float64(), rightValue.float64())
+	case token.REMAINDER:
+		rightValue := right.resolve()
+		return toValue_float64(math.Mod(leftValue.float64(), rightValue.float64()))
+
+		// Logical
+	case token.LOGICAL_AND:
+		left := leftValue.bool()
+		if !left {
+			return falseValue
+		}
+		return toValue_bool(right.resolve().bool())
+	case token.LOGICAL_OR:
+		left := leftValue.bool()
+		if left {
+			return trueValue
+		}
+		return toValue_bool(right.resolve().bool())
+
+		// Bitwise
+	case token.AND:
+		rightValue := right.resolve()
+		return toValue_int32(toInt32(leftValue) & toInt32(rightValue))
+	case token.OR:
+		rightValue := right.resolve()
+		return toValue_int32(toInt32(leftValue) | toInt32(rightValue))
+	case token.EXCLUSIVE_OR:
+		rightValue := right.resolve()
+		return toValue_int32(toInt32(leftValue) ^ toInt32(rightValue))
+
+		// Shift
+		// (Masking of 0x1f is to restrict the shift to a maximum of 31 places)
+	case token.SHIFT_LEFT:
+		rightValue := right.resolve()
+		return toValue_int32(toInt32(leftValue) << (toUint32(rightValue) & 0x1f))
+	case token.SHIFT_RIGHT:
+		rightValue := right.resolve()
+		return toValue_int32(toInt32(leftValue) >> (toUint32(rightValue) & 0x1f))
+	case token.UNSIGNED_SHIFT_RIGHT:
+		rightValue := right.resolve()
+		// Shifting an unsigned integer is a logical shift
+		return toValue_uint32(toUint32(leftValue) >> (toUint32(rightValue) & 0x1f))
+
+	case token.INSTANCEOF:
+		rightValue := right.resolve()
+		if !rightValue.IsObject() {
+			panic(self.panicTypeError("Expecting a function in instanceof check, but got: %v", rightValue))
+		}
+		return toValue_bool(rightValue._object().hasInstance(leftValue))
+
+	case token.IN:
+		rightValue := right.resolve()
+		if !rightValue.IsObject() {
+			panic(self.panicTypeError())
+		}
+		return toValue_bool(rightValue._object().hasProperty(leftValue.string()))
+	}
+
+	panic(hereBeDragons(operator))
+}
+
+func valueKindDispatchKey(left _valueKind, right _valueKind) int {
+	return (int(left) << 2) + int(right)
+}
+
+var equalDispatch map[int](func(Value, Value) bool) = makeEqualDispatch()
+
+func makeEqualDispatch() map[int](func(Value, Value) bool) {
+	key := valueKindDispatchKey
+	return map[int](func(Value, Value) bool){
+
+		key(valueNumber, valueObject): func(x Value, y Value) bool { return x.float64() == y.float64() },
+		key(valueString, valueObject): func(x Value, y Value) bool { return x.float64() == y.float64() },
+		key(valueObject, valueNumber): func(x Value, y Value) bool { return x.float64() == y.float64() },
+		key(valueObject, valueString): func(x Value, y Value) bool { return x.float64() == y.float64() },
+	}
+}
+
+type _lessThanResult int
+
+const (
+	lessThanFalse _lessThanResult = iota
+	lessThanTrue
+	lessThanUndefined
+)
+
+func calculateLessThan(left Value, right Value, leftFirst bool) _lessThanResult {
+
+	x := Value{}
+	y := x
+
+	if leftFirst {
+		x = toNumberPrimitive(left)
+		y = toNumberPrimitive(right)
+	} else {
+		y = toNumberPrimitive(right)
+		x = toNumberPrimitive(left)
+	}
+
+	result := false
+	if x.kind != valueString || y.kind != valueString {
+		x, y := x.float64(), y.float64()
+		if math.IsNaN(x) || math.IsNaN(y) {
+			return lessThanUndefined
+		}
+		result = x < y
+	} else {
+		x, y := x.string(), y.string()
+		result = x < y
+	}
+
+	if result {
+		return lessThanTrue
+	}
+
+	return lessThanFalse
+}
+
+// FIXME Probably a map is not the most efficient way to do this
+var lessThanTable [4](map[_lessThanResult]bool) = [4](map[_lessThanResult]bool){
+	// <
+	map[_lessThanResult]bool{
+		lessThanFalse:     false,
+		lessThanTrue:      true,
+		lessThanUndefined: false,
+	},
+
+	// >
+	map[_lessThanResult]bool{
+		lessThanFalse:     false,
+		lessThanTrue:      true,
+		lessThanUndefined: false,
+	},
+
+	// <=
+	map[_lessThanResult]bool{
+		lessThanFalse:     true,
+		lessThanTrue:      false,
+		lessThanUndefined: false,
+	},
+
+	// >=
+	map[_lessThanResult]bool{
+		lessThanFalse:     true,
+		lessThanTrue:      false,
+		lessThanUndefined: false,
+	},
+}
+
+func (self *_runtime) calculateComparison(comparator token.Token, left Value, right Value) bool {
+
+	// FIXME Use strictEqualityComparison?
+	// TODO This might be redundant now (with regards to evaluateComparison)
+	x := left.resolve()
+	y := right.resolve()
+
+	kindEqualKind := false
+	result := true
+	negate := false
+
+	switch comparator {
+	case token.LESS:
+		result = lessThanTable[0][calculateLessThan(x, y, true)]
+	case token.GREATER:
+		result = lessThanTable[1][calculateLessThan(y, x, false)]
+	case token.LESS_OR_EQUAL:
+		result = lessThanTable[2][calculateLessThan(y, x, false)]
+	case token.GREATER_OR_EQUAL:
+		result = lessThanTable[3][calculateLessThan(x, y, true)]
+	case token.STRICT_NOT_EQUAL:
+		negate = true
+		fallthrough
+	case token.STRICT_EQUAL:
+		if x.kind != y.kind {
+			result = false
+		} else {
+			kindEqualKind = true
+		}
+	case token.NOT_EQUAL:
+		negate = true
+		fallthrough
+	case token.EQUAL:
+		if x.kind == y.kind {
+			kindEqualKind = true
+		} else if x.kind <= valueNull && y.kind <= valueNull {
+			result = true
+		} else if x.kind <= valueNull || y.kind <= valueNull {
+			result = false
+		} else if x.kind <= valueString && y.kind <= valueString {
+			result = x.float64() == y.float64()
+		} else if x.kind == valueBoolean {
+			result = self.calculateComparison(token.EQUAL, toValue_float64(x.float64()), y)
+		} else if y.kind == valueBoolean {
+			result = self.calculateComparison(token.EQUAL, x, toValue_float64(y.float64()))
+		} else if x.kind == valueObject {
+			result = self.calculateComparison(token.EQUAL, toPrimitive(x), y)
+		} else if y.kind == valueObject {
+			result = self.calculateComparison(token.EQUAL, x, toPrimitive(y))
+		} else {
+			panic(hereBeDragons("Unable to test for equality: %v ==? %v", x, y))
+		}
+	default:
+		panic(fmt.Errorf("Unknown comparator %s", comparator.String()))
+	}
+
+	if kindEqualKind {
+		switch x.kind {
+		case valueUndefined, valueNull:
+			result = true
+		case valueNumber:
+			x := x.float64()
+			y := y.float64()
+			if math.IsNaN(x) || math.IsNaN(y) {
+				result = false
+			} else {
+				result = x == y
+			}
+		case valueString:
+			result = x.string() == y.string()
+		case valueBoolean:
+			result = x.bool() == y.bool()
+		case valueObject:
+			result = x._object() == y._object()
+		default:
+			goto ERROR
+		}
+	}
+
+	if negate {
+		result = !result
+	}
+
+	return result
+
+ERROR:
+	panic(hereBeDragons("%v (%v) %s %v (%v)", x, x.kind, comparator, y, y.kind))
+}