1// run
2
3//go:build !js && !wasip1 && gc
4
5// Copyright 2018 The Go Authors. All rights reserved.
6// Use of this source code is governed by a BSD-style
7// license that can be found in the LICENSE file.
8
9// Verify the impact of line directives on error positions and position formatting.
10
11package main
12
13import (
14	"io/ioutil"
15	"log"
16	"os"
17	"os/exec"
18	"strings"
19)
20
21// Each of these tests is expected to fail (missing package clause)
22// at the position determined by the preceding line directive.
23var tests = []struct {
24	src, pos string
25}{
26	{"//line :10\n", ":10:"},                   // no filename means no filename
27	{"//line :10:4\n", "filename:10:4"},        // no filename means use existing filename
28	{"//line foo.go:10\n", "foo.go:10:"},       // no column means don't print a column
29	{"//line foo.go:10:4\n", "foo.go:10:4:"},   // column means print a column
30	{"//line foo.go:10:4\n\n", "foo.go:11:1:"}, // relative columns start at 1 after newline
31
32	{"/*line :10*/", ":10:"},
33	{"/*line :10:4*/", "filename:10:4"},
34	{"/*line foo.go:10*/", "foo.go:10:"},
35	{"/*line foo.go:10:4*/", "foo.go:10:4:"},
36	{"/*line foo.go:10:4*/\n", "foo.go:11:1:"},
37}
38
39func main() {
40	f, err := ioutil.TempFile("", "issue22662b.go")
41	if err != nil {
42		log.Fatal(err)
43	}
44	f.Close()
45	defer os.Remove(f.Name())
46
47	for _, test := range tests {
48		if err := ioutil.WriteFile(f.Name(), []byte(test.src), 0660); err != nil {
49			log.Fatal(err)
50		}
51
52		out, err := exec.Command("go", "tool", "compile", "-p=p", f.Name()).CombinedOutput()
53		if err == nil {
54			log.Fatalf("expected compiling\n---\n%s\n---\nto fail", test.src)
55		}
56
57		errmsg := strings.Replace(string(out), f.Name(), "filename", -1) // use "filename" instead of actual (long) filename
58		if !strings.HasPrefix(errmsg, test.pos) {
59			log.Fatalf("%q: got %q; want position %q", test.src, errmsg, test.pos)
60		}
61	}
62}
63