parsing - 如何在 PHP-Parser 中隐藏属性

Question

我正在使用PHP-Parser来解析 PHP 代码，并以 Json 格式获取 AST。我想问如何在没有属性的情况下获得结果（startLine、endLine、comment 等）

Answer 1

尽管计算成本很高，但您可以递归地遍历输出并删除这些属性。

或者

另一种可能更容易的方法是扩展一个已实现的 Php Parser 类并覆盖protected function createCommentNopAttributes(array $comments) 以返回您想要的属性，或者在这种情况下不返回任何属性。

例如，假设我们打算解析Php7代码，我们可以创建自己的自定义解析器

class MyCustomPhp7Parser extends \PhpParser\Parser\Php7 {
   //no need to implement the other methods as we are inheriting from a concrete class
   
   //override method inherited from https://github.com/nikic/PHP-Parser/blob/master/lib/PhpParser/ParserAbstract.php
   protected function createCommentNopAttributes(array $comments) {
       $attributes = ['comments' => []]; //return data as desired
       return $attributes;
   }
} 

然后您可以使用您的自定义解析器实现

<?php

use PhpParser\ParserFactory;

$code = <<<'CODE'
<?php

/** @param string $msg */
function printLine($msg) {
    echo $msg, "\n";
}
CODE;

$parser = new MyCustomPhp7Parser(
   new \PhpParser\Lexer\Emulative(), //desired lexer
   [] //additional options
);

try {
    $stmts = $parser->parse($code);

    echo json_encode($stmts, JSON_PRETTY_PRINT), "\n";
} catch (PhpParser\Error $e) {
    echo 'Parse Error: ', $e->getMessage();
}

检索

[
    {
        "nodeType": "Stmt_Function",
        "byRef": false,
        "name": {
            "nodeType": "Identifier",
            "name": "printLine",
            "attributes": {
                "startLine": 4,
                "endLine": 4
            }
        },
        "params": [
            {
                "nodeType": "Param",
                "type": null,
                "byRef": false,
                "variadic": false,
                "var": {
                    "nodeType": "Expr_Variable",
                    "name": "msg",
                    "attributes": {
                        "startLine": 4,
                        "endLine": 4
                    }
                },
                "default": null,
                "attributes": {
                    "startLine": 4,
                    "endLine": 4
                }
            }
        ],
        "returnType": null,
        "stmts": [
            {
                "nodeType": "Stmt_Echo",
                "exprs": [
                    {
                        "nodeType": "Expr_Variable",
                        "name": "msg",
                        "attributes": {
                            "startLine": 5,
                            "endLine": 5
                        }
                    },
                    {
                        "nodeType": "Scalar_String",
                        "value": "\n",
                        "attributes": {
                            "startLine": 5,
                            "endLine": 5,
                            "kind": 2
                        }
                    }
                ],
                "attributes": {
                    "startLine": 5,
                    "endLine": 5
                }
            }
        ],
        "attributes": {
            "comments": [
                
            ],
   
        }
    }
]