Update vendor (#1560)

vendor/github.com/d5/tengo/v2/README.md

@@ -4,7 +4,7 @@
 
 # The Tengo Language
 
-[![GoDoc](https://godoc.org/github.com/d5/tengo?status.svg)](https://godoc.org/github.com/d5/tengo)
+[![GoDoc](https://godoc.org/github.com/d5/tengo/v2?status.svg)](https://godoc.org/github.com/d5/tengo/v2)
 ![test](https://github.com/d5/tengo/workflows/test/badge.svg)
 [![Go Report Card](https://goreportcard.com/badge/github.com/d5/tengo)](https://goreportcard.com/report/github.com/d5/tengo)
 
@@ -53,19 +53,19 @@ fmt.println(sum("", [1, 2, 3]))  // "123"
 
 | | fib(35) | fibt(35) |  Language (Type)  |
 | :--- |    ---: |     ---: |  :---: |
-| [**Tengo**](https://github.com/d5/tengo) | `2,931ms` | `4ms` | Tengo (VM) |
-| [go-lua](https://github.com/Shopify/go-lua) | `4,824ms` | `4ms` | Lua (VM) |
-| [GopherLua](https://github.com/yuin/gopher-lua) | `5,365ms` | `4ms` | Lua (VM) |
-| [goja](https://github.com/dop251/goja) | `5,533ms` | `5ms` | JavaScript (VM) |
-| [starlark-go](https://github.com/google/starlark-go) | `11,495ms` | `5ms` | Starlark (Interpreter) |
-| [Yaegi](https://github.com/containous/yaegi) | `15,645ms` | `12ms` | Yaegi (Interpreter) |
-| [gpython](https://github.com/go-python/gpython) | `16,322ms` | `5ms` | Python (Interpreter) |
-| [otto](https://github.com/robertkrimen/otto) | `73,093ms` | `10ms` | JavaScript (Interpreter) |
-| [Anko](https://github.com/mattn/anko) | `79,809ms` | `8ms` | Anko (Interpreter) |
+| [**Tengo**](https://github.com/d5/tengo) | `2,315ms` | `3ms` | Tengo (VM) |
+| [go-lua](https://github.com/Shopify/go-lua) | `4,028ms` | `3ms` | Lua (VM) |
+| [GopherLua](https://github.com/yuin/gopher-lua) | `4,409ms` | `3ms` | Lua (VM) |
+| [goja](https://github.com/dop251/goja) | `5,194ms` | `4ms` | JavaScript (VM) |
+| [starlark-go](https://github.com/google/starlark-go) | `6,954ms` | `3ms` | Starlark (Interpreter) |
+| [gpython](https://github.com/go-python/gpython) | `11,324ms` | `4ms` | Python (Interpreter) |
+| [Yaegi](https://github.com/containous/yaegi) | `11,715ms` | `10ms` | Yaegi (Interpreter) |
+| [otto](https://github.com/robertkrimen/otto) | `48,539ms` | `6ms` | JavaScript (Interpreter) |
+| [Anko](https://github.com/mattn/anko) | `52,821ms` | `6ms` | Anko (Interpreter) |
 | - | - | - | - |
-| Go | `53ms` | `3ms` | Go (Native) |
-| Lua | `1,612ms` | `3ms` | Lua (Native) |
-| Python | `2,632ms` | `23ms` | Python 2 (Native) |
+| Go | `47ms` | `2ms` | Go (Native) |
+| Lua | `756ms` | `2ms` | Lua (Native) |
+| Python | `1,907ms` | `14ms` | Python2 (Native) |
 
 _* [fib(35)](https://github.com/d5/tengobench/blob/master/code/fib.tengo):
 Fibonacci(35)_  
@@ -93,21 +93,18 @@ import (
 )
 
 func main() {
-	// Tengo script code
-	src := `
-each := func(seq, fn) {
+	// create a new Script instance
+	script := tengo.NewScript([]byte(
+`each := func(seq, fn) {
     for x in seq { fn(x) }
 }
 
 sum := 0
 mul := 1
 each([a, b, c, d], func(x) {
-	sum += x
-	mul *= x
-})`
-
-	// create a new Script instance
-	script := tengo.NewScript([]byte(src))
+    sum += x
+    mul *= x
+})`))
 
 	// set values
 	_ = script.Add("a", 1)
@@ -128,6 +125,19 @@ each([a, b, c, d], func(x) {
 }
 ```
 
+Or, if you need to evaluate a simple expression, you can use [Eval](https://pkg.go.dev/github.com/d5/tengo/v2#Eval) function instead:
+
+
+```golang
+res, err := tengo.Eval(ctx,
+	`input ? "success" : "fail"`,
+	map[string]interface{}{"input": 1})
+if err != nil {
+	panic(err)
+}
+fmt.Println(res) // "success"
+```
+
 ## References
 
 - [Language Syntax](https://github.com/d5/tengo/blob/master/docs/tutorial.md)

vendor/github.com/d5/tengo/v2/eval.go

@@ -0,0 +1,35 @@
+package tengo
+
+import (
+	"context"
+	"fmt"
+	"strings"
+)
+
+// Eval compiles and executes given expr with params, and returns an
+// evaluated value. expr must be an expression. Otherwise it will fail to
+// compile. Expression must not use or define variable "__res__" as it's
+// reserved for the internal usage.
+func Eval(
+	ctx context.Context,
+	expr string,
+	params map[string]interface{},
+) (interface{}, error) {
+	expr = strings.TrimSpace(expr)
+	if expr == "" {
+		return nil, fmt.Errorf("empty expression")
+	}
+
+	script := NewScript([]byte(fmt.Sprintf("__res__ := (%s)", expr)))
+	for pk, pv := range params {
+		err := script.Add(pk, pv)
+		if err != nil {
+			return nil, fmt.Errorf("script add: %w", err)
+		}
+	}
+	compiled, err := script.RunContext(ctx)
+	if err != nil {
+		return nil, fmt.Errorf("script run: %w", err)
+	}
+	return compiled.Get("__res__").Value(), nil
+}