1 | // Copyright 2020 The Go Authors. All rights reserved. |
---|---|
2 | // Use of this source code is governed by a BSD-style |
3 | // license that can be found in the LICENSE file. |
4 | |
5 | package gocommand |
6 | |
7 | import ( |
8 | "context" |
9 | "fmt" |
10 | "regexp" |
11 | "strings" |
12 | ) |
13 | |
14 | // GoVersion reports the minor version number of the highest release |
15 | // tag built into the go command on the PATH. |
16 | // |
17 | // Note that this may be higher than the version of the go tool used |
18 | // to build this application, and thus the versions of the standard |
19 | // go/{scanner,parser,ast,types} packages that are linked into it. |
20 | // In that case, callers should either downgrade to the version of |
21 | // go used to build the application, or report an error that the |
22 | // application is too old to use the go command on the PATH. |
23 | func GoVersion(ctx context.Context, inv Invocation, r *Runner) (int, error) { |
24 | inv.Verb = "list" |
25 | inv.Args = []string{"-e", "-f", `{{context.ReleaseTags}}`, `--`, `unsafe`} |
26 | inv.Env = append(append([]string{}, inv.Env...), "GO111MODULE=off") |
27 | // Unset any unneeded flags, and remove them from BuildFlags, if they're |
28 | // present. |
29 | inv.ModFile = "" |
30 | inv.ModFlag = "" |
31 | var buildFlags []string |
32 | for _, flag := range inv.BuildFlags { |
33 | // Flags can be prefixed by one or two dashes. |
34 | f := strings.TrimPrefix(strings.TrimPrefix(flag, "-"), "-") |
35 | if strings.HasPrefix(f, "mod=") || strings.HasPrefix(f, "modfile=") { |
36 | continue |
37 | } |
38 | buildFlags = append(buildFlags, flag) |
39 | } |
40 | inv.BuildFlags = buildFlags |
41 | stdoutBytes, err := r.Run(ctx, inv) |
42 | if err != nil { |
43 | return 0, err |
44 | } |
45 | stdout := stdoutBytes.String() |
46 | if len(stdout) < 3 { |
47 | return 0, fmt.Errorf("bad ReleaseTags output: %q", stdout) |
48 | } |
49 | // Split up "[go1.1 go1.15]" and return highest go1.X value. |
50 | tags := strings.Fields(stdout[1 : len(stdout)-2]) |
51 | for i := len(tags) - 1; i >= 0; i-- { |
52 | var version int |
53 | if _, err := fmt.Sscanf(tags[i], "go1.%d", &version); err != nil { |
54 | continue |
55 | } |
56 | return version, nil |
57 | } |
58 | return 0, fmt.Errorf("no parseable ReleaseTags in %v", tags) |
59 | } |
60 | |
61 | // GoVersionString reports the go version string as shown in `go version` command output. |
62 | // When `go version` outputs in non-standard form, this returns an empty string. |
63 | func GoVersionString(ctx context.Context, inv Invocation, r *Runner) (string, error) { |
64 | inv.Verb = "version" |
65 | goVersion, err := r.Run(ctx, inv) |
66 | if err != nil { |
67 | return "", err |
68 | } |
69 | return parseGoVersionOutput(goVersion.Bytes()), nil |
70 | } |
71 | |
72 | func parseGoVersionOutput(data []byte) string { |
73 | re := regexp.MustCompile(`^go version (go\S+|devel \S+)`) |
74 | m := re.FindSubmatch(data) |
75 | if len(m) != 2 { |
76 | return "" // unrecognized version |
77 | } |
78 | return string(m[1]) |
79 | } |
80 |
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