Update tengo vendor and load the stdlib. Fixes #789 (#792)

1 files changed, 116 insertions, 0 deletions

diff --git a/vendor/github.com/d5/tengo/stdlib/fmt.go b/vendor/github.com/d5/tengo/stdlib/fmt.go
new file mode 100644
index 00000000..9c75fc33
--- /dev/null
+++ b/vendor/github.com/d5/tengo/stdlib/fmt.go
@@ -0,0 +1,116 @@
+package stdlib
+
+import (
+	"fmt"
+
+	"github.com/d5/tengo"
+	"github.com/d5/tengo/objects"
+)
+
+var fmtModule = map[string]objects.Object{
+	"print":   &objects.UserFunction{Name: "print", Value: fmtPrint},
+	"printf":  &objects.UserFunction{Name: "printf", Value: fmtPrintf},
+	"println": &objects.UserFunction{Name: "println", Value: fmtPrintln},
+	"sprintf": &objects.UserFunction{Name: "sprintf", Value: fmtSprintf},
+}
+
+func fmtPrint(args ...objects.Object) (ret objects.Object, err error) {
+	printArgs, err := getPrintArgs(args...)
+	if err != nil {
+		return nil, err
+	}
+
+	_, _ = fmt.Print(printArgs...)
+
+	return nil, nil
+}
+
+func fmtPrintf(args ...objects.Object) (ret objects.Object, err error) {
+	numArgs := len(args)
+	if numArgs == 0 {
+		return nil, objects.ErrWrongNumArguments
+	}
+
+	format, ok := args[0].(*objects.String)
+	if !ok {
+		return nil, objects.ErrInvalidArgumentType{
+			Name:     "format",
+			Expected: "string",
+			Found:    args[0].TypeName(),
+		}
+	}
+	if numArgs == 1 {
+		fmt.Print(format)
+		return nil, nil
+	}
+
+	formatArgs := make([]interface{}, numArgs-1, numArgs-1)
+	for idx, arg := range args[1:] {
+		formatArgs[idx] = objects.ToInterface(arg)
+	}
+
+	fmt.Printf(format.Value, formatArgs...)
+
+	return nil, nil
+}
+
+func fmtPrintln(args ...objects.Object) (ret objects.Object, err error) {
+	printArgs, err := getPrintArgs(args...)
+	if err != nil {
+		return nil, err
+	}
+
+	printArgs = append(printArgs, "\n")
+	_, _ = fmt.Print(printArgs...)
+
+	return nil, nil
+}
+
+func fmtSprintf(args ...objects.Object) (ret objects.Object, err error) {
+	numArgs := len(args)
+	if numArgs == 0 {
+		return nil, objects.ErrWrongNumArguments
+	}
+
+	format, ok := args[0].(*objects.String)
+	if !ok {
+		return nil, objects.ErrInvalidArgumentType{
+			Name:     "format",
+			Expected: "string",
+			Found:    args[0].TypeName(),
+		}
+	}
+	if numArgs == 1 {
+		return format, nil // okay to return 'format' directly as String is immutable
+	}
+
+	formatArgs := make([]interface{}, numArgs-1, numArgs-1)
+	for idx, arg := range args[1:] {
+		formatArgs[idx] = objects.ToInterface(arg)
+	}
+
+	s := fmt.Sprintf(format.Value, formatArgs...)
+
+	if len(s) > tengo.MaxStringLen {
+		return nil, objects.ErrStringLimit
+	}
+
+	return &objects.String{Value: s}, nil
+}
+
+func getPrintArgs(args ...objects.Object) ([]interface{}, error) {
+	var printArgs []interface{}
+	l := 0
+	for _, arg := range args {
+		s, _ := objects.ToString(arg)
+		slen := len(s)
+		if l+slen > tengo.MaxStringLen { // make sure length does not exceed the limit
+			return nil, objects.ErrStringLimit
+		}
+		l += slen
+
+		printArgs = append(printArgs, s)
+	}
+
+	return printArgs, nil
+}