php-parser/README.md
2018-04-10 23:45:26 +03:00

3.2 KiB

PHP Parser written in Go

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Try it online: demo

Features:

  • Fully support PHP 5 and PHP 7 syntax
  • Abstract syntax tree (AST) representation
  • Traversing AST
  • Namespace resolver
  • Able to parse syntax-invalid PHP files

Roadmap

  • Control Flow Graph (CFG)
  • PhpDocComment parser
  • Stabilize api

Install

go get github.com/z7zmey/php-parser

CLI

php-parser [-php5] <path> ...

Dump AST to stdout.

Example

package main

import (
	"fmt"
	"bytes"
	"os"

	"github.com/z7zmey/php-parser/php7"
	"github.com/z7zmey/php-parser/visitor"
)

func main() {
	src := bytes.NewBufferString(`<? echo "Hello world";`)

	parser := php7.NewParser(src, "example.php")
	parser.Parse()

	for _, e := range parser.GetErrors() {
		fmt.Println(e)
	}

	visitor := visitor.Dumper{
		Writer:    os.Stdout,
		Indent:    "",
		Comments:  parser.GetComments(),
		Positions: parser.GetPositions(),
	}

	rootNode := parser.GetRootNode()
	rootNode.Walk(visitor)
}

Namespace resolver

Namespace resolver is a visitor that resolves nodes fully qualified name and saves into map[node.Node]string structure

  • For Class, Interface, Trait, Function, Constant nodes it saves name with current namespace.
  • For Name, Relative, FullyQualified nodes it resolves use aliases and saves a fully qualified name.

Parsing syntax-invalid PHP files

If we try to parse $a$b; then the parser triggers error 'syntax error: unexpected T_VARIABLE'. Token $b is unexpected, but parser recovers parsing process and returns $b; statement to AST, because it is syntactically correct.

Pretty printer

nodes := &stmt.StmtList{
	Stmts: []node.Node{
		&stmt.Namespace{
			NamespaceName: &name.Name{Parts: []node.Node{&name.NamePart{Value: "Foo"}}},
		},
		&stmt.Class{
			Modifiers: []node.Node{&node.Identifier{Value: "abstract"}},
			ClassName: &name.Name{Parts: []node.Node{&name.NamePart{Value: "Bar"}}},
			Extends: &name.Name{Parts: []node.Node{&name.NamePart{Value: "Baz"}}},
			Stmts: []node.Node{
				&stmt.ClassMethod{
					Modifiers:  []node.Node{&node.Identifier{Value: "public"}},
					MethodName: &node.Identifier{Value: "greet"},
					Stmts: []node.Node{
						&stmt.Echo{
							Exprs: []node.Node{
								&scalar.String{Value: "'Hello world'"},
							},
						},
					},
				},
			},
		},
	},
}

file := os.Stdout
p := printer.NewPrinter(file, "    ")
p.PrintFile(nodes)

Output:

<?php
namespace Foo;
abstract class Bar extends Baz
{
    public function greet()
    {
        echo 'Hello world';
    }
}