|  | // run | 
|  |  | 
|  | //go:build !nacl && !js && !wasip1 && !android && gc | 
|  |  | 
|  | // Copyright 2016 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 main | 
|  |  | 
|  | import ( | 
|  | "bytes" | 
|  | "log" | 
|  | "os/exec" | 
|  | "strings" | 
|  | ) | 
|  |  | 
|  | func main() { | 
|  | checkLinkOutput("", "-B argument must start with 0x") | 
|  | checkLinkOutput("0", "-B argument must start with 0x") | 
|  | checkLinkOutput("0x", "usage") | 
|  | checkLinkOutput("0x0", "-B argument must have even number of digits") | 
|  | checkLinkOutput("0x00", "usage") | 
|  | checkLinkOutput("0xYZ", "-B argument contains invalid hex digit") | 
|  | checkLinkOutput("0x"+strings.Repeat("00", 32), "usage") | 
|  | checkLinkOutput("0x"+strings.Repeat("00", 33), "-B option too long (max 32 digits)") | 
|  | } | 
|  |  | 
|  | func checkLinkOutput(buildid string, message string) { | 
|  | cmd := exec.Command("go", "tool", "link", "-B", buildid) | 
|  | out, err := cmd.CombinedOutput() | 
|  | if err == nil { | 
|  | log.Fatalf("expected cmd/link to fail") | 
|  | } | 
|  |  | 
|  | firstLine := string(bytes.SplitN(out, []byte("\n"), 2)[0]) | 
|  | if strings.HasPrefix(firstLine, "panic") { | 
|  | log.Fatalf("cmd/link panicked:\n%s", out) | 
|  | } | 
|  |  | 
|  | if !strings.Contains(firstLine, message) { | 
|  | log.Fatalf("cmd/link output did not include expected message %q: %s", message, firstLine) | 
|  | } | 
|  | } |