chore: upgrade coredns version (#550)

vendor/github.com/expr-lang/expr/conf/config.go

@@ -0,0 +1,101 @@
+package conf
+
+import (
+	"fmt"
+	"reflect"
+
+	"github.com/expr-lang/expr/ast"
+	"github.com/expr-lang/expr/builtin"
+	"github.com/expr-lang/expr/checker/nature"
+	"github.com/expr-lang/expr/vm/runtime"
+)
+
+const (
+	// DefaultMemoryBudget represents an upper limit of memory usage
+	DefaultMemoryBudget uint = 1e6
+
+	// DefaultMaxNodes represents an upper limit of AST nodes
+	DefaultMaxNodes uint = 10000
+)
+
+type FunctionsTable map[string]*builtin.Function
+
+type Config struct {
+	EnvObject    any
+	Env          nature.Nature
+	Expect       reflect.Kind
+	ExpectAny    bool
+	Optimize     bool
+	Strict       bool
+	Profile      bool
+	MaxNodes     uint
+	MemoryBudget uint
+	ConstFns     map[string]reflect.Value
+	Visitors     []ast.Visitor
+	Functions    FunctionsTable
+	Builtins     FunctionsTable
+	Disabled     map[string]bool // disabled builtins
+}
+
+// CreateNew creates new config with default values.
+func CreateNew() *Config {
+	c := &Config{
+		Optimize:     true,
+		MaxNodes:     DefaultMaxNodes,
+		MemoryBudget: DefaultMemoryBudget,
+		ConstFns:     make(map[string]reflect.Value),
+		Functions:    make(map[string]*builtin.Function),
+		Builtins:     make(map[string]*builtin.Function),
+		Disabled:     make(map[string]bool),
+	}
+	for _, f := range builtin.Builtins {
+		c.Builtins[f.Name] = f
+	}
+	return c
+}
+
+// New creates new config with environment.
+func New(env any) *Config {
+	c := CreateNew()
+	c.WithEnv(env)
+	return c
+}
+
+func (c *Config) WithEnv(env any) {
+	c.EnvObject = env
+	c.Env = Env(env)
+	c.Strict = c.Env.Strict
+}
+
+func (c *Config) ConstExpr(name string) {
+	if c.EnvObject == nil {
+		panic("no environment is specified for ConstExpr()")
+	}
+	fn := reflect.ValueOf(runtime.Fetch(c.EnvObject, name))
+	if fn.Kind() != reflect.Func {
+		panic(fmt.Errorf("const expression %q must be a function", name))
+	}
+	c.ConstFns[name] = fn
+}
+
+type Checker interface {
+	Check()
+}
+
+func (c *Config) Check() {
+	for _, v := range c.Visitors {
+		if c, ok := v.(Checker); ok {
+			c.Check()
+		}
+	}
+}
+
+func (c *Config) IsOverridden(name string) bool {
+	if _, ok := c.Functions[name]; ok {
+		return true
+	}
+	if _, ok := c.Env.Get(name); ok {
+		return true
+	}
+	return false
+}