node: add bailout cases for eval() and extract()

node.go

@@ -14,6 +14,8 @@ import (
 	"github.com/z7zmey/php-parser/node/name"
 	"github.com/z7zmey/php-parser/node/scalar"
 	"github.com/z7zmey/php-parser/node/stmt"
+
+	"php2go/parseutil"
 )
 
 func nodeTypeString(n node.Node) string {
@@ -1192,6 +1194,10 @@ func (this *conversionState) convertNoFreeFloating(n_ node.Node) (string, error)
 				callParams = append(callParams, `-1`) // replaceAll
 				// There is a strings.ReplaceAll() added in go1.12 (2018), which is still pretty recent i.e. not in Debian Stable (buster)
 			}
+
+		} else if funcName == `extract` {
+			return "", parseErr{n, fmt.Errorf("Unsupported dynamic function `\\extract()`")}
+
 		}
 
 		return funcName + "(" + strings.Join(callParams, ", ") + ")", nil // expr only, no semicolon/newline
@@ -1320,6 +1326,9 @@ func (this *conversionState) convertNoFreeFloating(n_ node.Node) (string, error)
 			return "os.Exit(" + child + ")", nil
 		}
 
+	case *expr.Eval:
+		return "", parseErr{n, fmt.Errorf("Unsupported use of eval()")}
+
 	case *expr.PreInc:
 		// """In Go, i++ is a statement, not an expression. So you can't use its value in another expression such as a function call."""
 		v, err := this.convert(n.Variable)
@@ -2105,7 +2114,7 @@ func (this *conversionState) convertFunctionCommon(params []node.Node, returnTyp
 // any assignment expressions
 func hasInteriorAssignment(n node.Node) (hasAnyAssign bool, err error) {
 
-	err = walk(n, func(n node.Node) error {
+	err = parseutil.SimpleWalk(n, func(n node.Node) error {
 		if _, ok := n.(*assign.Assign); ok {
 			hasAnyAssign = true
 		}