Parse Function Comments From Source in Golang

astFuncParser.go

package main

import (
	"fmt"
	"go/ast"
	"go/parser"
	"go/token"
	"log"
)

func main() {
	fset := token.NewFileSet()
	filename := ""
	src := `
package example
var a int = 3

// This is a function comment
// and it is continued on this line
func doThing() {}
`

	f, err := parser.ParseFile(fset, filename, src, parser.ParseComments)

	if err != nil {
		log.Fatal(err)
		return
	}

	var fv funcVisitor
	ast.Walk(&fv, f)

	fmt.Println(fv)
}

type funcData struct {
	identity string
	comment  string
}

type funcVisitor struct {
	data []funcData
}

func (fv *funcVisitor) Visit(n ast.Node) ast.Visitor {
	if val, ok := n.(*ast.FuncDecl); ok {
		fv.data = append(fv.data, funcData{
			identity: val.Name.String(),
			comment:  val.Doc.Text(),
		})
	}

	return fv
}