expressions working

Signed-off-by: Casey Lee <cplee@nektos.com>

vendor/github.com/robertkrimen/otto/builtin_regexp.go

@@ -0,0 +1,65 @@
+package otto
+
+import (
+	"fmt"
+)
+
+// RegExp
+
+func builtinRegExp(call FunctionCall) Value {
+	pattern := call.Argument(0)
+	flags := call.Argument(1)
+	if object := pattern._object(); object != nil {
+		if object.class == "RegExp" && flags.IsUndefined() {
+			return pattern
+		}
+	}
+	return toValue_object(call.runtime.newRegExp(pattern, flags))
+}
+
+func builtinNewRegExp(self *_object, argumentList []Value) Value {
+	return toValue_object(self.runtime.newRegExp(
+		valueOfArrayIndex(argumentList, 0),
+		valueOfArrayIndex(argumentList, 1),
+	))
+}
+
+func builtinRegExp_toString(call FunctionCall) Value {
+	thisObject := call.thisObject()
+	source := thisObject.get("source").string()
+	flags := []byte{}
+	if thisObject.get("global").bool() {
+		flags = append(flags, 'g')
+	}
+	if thisObject.get("ignoreCase").bool() {
+		flags = append(flags, 'i')
+	}
+	if thisObject.get("multiline").bool() {
+		flags = append(flags, 'm')
+	}
+	return toValue_string(fmt.Sprintf("/%s/%s", source, flags))
+}
+
+func builtinRegExp_exec(call FunctionCall) Value {
+	thisObject := call.thisObject()
+	target := call.Argument(0).string()
+	match, result := execRegExp(thisObject, target)
+	if !match {
+		return nullValue
+	}
+	return toValue_object(execResultToArray(call.runtime, target, result))
+}
+
+func builtinRegExp_test(call FunctionCall) Value {
+	thisObject := call.thisObject()
+	target := call.Argument(0).string()
+	match, _ := execRegExp(thisObject, target)
+	return toValue_bool(match)
+}
+
+func builtinRegExp_compile(call FunctionCall) Value {
+	// This (useless) function is deprecated, but is here to provide some
+	// semblance of compatibility.
+	// Caveat emptor: it may not be around for long.
+	return Value{}
+}