goastch (GO AST matCH)

Introduction

Inspired by ast matcher. There are four different basic categories of matchers:

• Node Matchers: Matchers that match a specific type of AST node.
• Attributive Matchers: Matchers that match attributes on AST nodes.
• Logical Matchers: Matchers that allow logic between matchers.
• Traversal Matchers: Matchers that allow traversal between AST nodes.

Demo of ga toy

Using as a lib

Find ‘ShortVarDecl’ from a file, and binding these to ‘bindID’.

package main

import (
	"fmt"
	"go/parser"
	"go/printer"
	"go/token"
	"log"
	"os"

	"github.com/helloyi/goastch"
	. "github.com/helloyi/goastch/goastcher"
)

func main() {
	g := HasDescendant(ShortVarDecl(Anything()).Bind("bindID"))

	src := `package foo
	func bar() {
    a := []int{}
    var b []int
    c := []string{}
	}`

	fset := token.NewFileSet()
	file, _ := parser.ParseFile(fset, "example", src, 0)
	bindings, err := goastch.Find(file, nil, g)
	if err != nil {
		log.Fatalln(err)
	}
	for key, list := range bindings {
		for _, node := range list {
			fmt.Printf("%s: ", key)
			_ = printer.Fprint(os.Stdout, fset, node)
			fmt.Println()
		}
	}
}