You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: srctesting.go
    path of file: ./repos/gopherjs/internal/srctesting
    
    the code of the file until where you have to start completion: // Package srctesting contains common helpers for unit testing source code
// analysis and transformation.
package srctesting

import (
	"bytes"
	"go/ast"
	
    
func Format(t *testing.T, fset *token.FileSet, node any) string {
	t.Helper()
	buf := &bytes.Buffer{}
	if err := format.Node(buf, fset, node); err != nil {
		t.Fatalf("Failed to format AST node %T: %s", node, err)
	}
	return buf.String()
}