Fails to identify defers in nested BlockStmt

[Dennis Fischer]

Defers in nested BlockStmt are not detected.

package main

import (
	"fmt"
)

func main() {
	for i := 0; i < 5; i++ {
		defer fmt.Println("Hello, playground")
		{
			defer fmt.Println("Hello, playground") //Not detected
		}
		fmt.Println(i)
	}
}

Bug is in

dll/dll.go

Lines 42 to 50 in adb0f52

 switch ty := n.(type) { 
 case *ast.ForStmt: 
 	for _, stmt := range ty.Body.List { 
 		if d, ok := stmt.(*ast.DeferStmt); ok { 
 			w.reports = append(w.reports, 
 				&report{sourceName: sourceName, lineNumber: source.Line(d.Pos())}) 
 		} 
 	} 
 } 

Instead of looking into the BlockStmt of the for loop all child elements have to be checked. I haven't worked much with ast package, but I'd assume that you'd need another walker+visitor here.

[Garrett Squire]

Thanks for this, I had totally overlooked those types of statements and expressions initially. I believe there is a better way than trying to account for all nodes that can contain defer statements so I will have to take a further look.