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: solve_failures.go
    path of file: ./repos/dep/gps
    
    the code of the file until where you have to start completion: // Copyright 2017 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package gps

import (
	"bytes"
	"fmt"
	"sort"
	"strings"
)

func a2vs(a atom) string {
	if a.v == rootRev || a.v == nil {
		return "(root)"
	}

	return fmt.Sprintf("%s@%s", a.id, a.v
    
func (e *wrongCaseFailure) Error() string {
	if len(e.badcase) == 1 {
		str := "Could not introduce %s; imports amongst its packages establish %q as the canonical casing for root, but %s tried to import it as %q"
		return fmt.Sprintf(str, a2vs(e.goal.depender), e.correct, a2vs(e.badcase[0].depender), e.badcase[0].dep.Ident.ProjectRoot)
	}

	var buf bytes.Buffer

	str := "Could not introduce %s; imports amongst its packages establish %q as the canonical casing for root, but the following projects tried to import it as %q"
	fmt.Fprintf(&buf, str, a2vs(e.goal.depender), e.correct, e.badcase[0].dep.Ident.ProjectRoot)

	for _, c := range e.badcase {
		fmt.Fprintf(&buf, "\t%s\n", a2vs(c.depender))
	}

	return buf.String()
}