| // Copyright 2020 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 gocommand |
| |
| import ( |
| "context" |
| "fmt" |
| "regexp" |
| "strings" |
| ) |
| |
| // GoVersion reports the minor version number of the highest release |
| // tag built into the go command on the PATH. |
| // |
| // Note that this may be higher than the version of the go tool used |
| // to build this application, and thus the versions of the standard |
| // go/{scanner,parser,ast,types} packages that are linked into it. |
| // In that case, callers should either downgrade to the version of |
| // go used to build the application, or report an error that the |
| // application is too old to use the go command on the PATH. |
| func GoVersion(ctx context.Context, inv Invocation, r *Runner) (int, error) { |
| inv.Verb = "list" |
| inv.Args = []string{"-e", "-f", `{{context.ReleaseTags}}`, `--`, `unsafe`} |
| inv.Env = append(append([]string{}, inv.Env...), "GO111MODULE=off") |
| // Unset any unneeded flags, and remove them from BuildFlags, if they're |
| // present. |
| inv.ModFile = "" |
| inv.ModFlag = "" |
| var buildFlags []string |
| for _, flag := range inv.BuildFlags { |
| // Flags can be prefixed by one or two dashes. |
| f := strings.TrimPrefix(strings.TrimPrefix(flag, "-"), "-") |
| if strings.HasPrefix(f, "mod=") || strings.HasPrefix(f, "modfile=") { |
| continue |
| } |
| buildFlags = append(buildFlags, flag) |
| } |
| inv.BuildFlags = buildFlags |
| stdoutBytes, err := r.Run(ctx, inv) |
| if err != nil { |
| return 0, err |
| } |
| stdout := stdoutBytes.String() |
| if len(stdout) < 3 { |
| return 0, fmt.Errorf("bad ReleaseTags output: %q", stdout) |
| } |
| // Split up "[go1.1 go1.15]" and return highest go1.X value. |
| tags := strings.Fields(stdout[1 : len(stdout)-2]) |
| for i := len(tags) - 1; i >= 0; i-- { |
| var version int |
| if _, err := fmt.Sscanf(tags[i], "go1.%d", &version); err != nil { |
| continue |
| } |
| return version, nil |
| } |
| return 0, fmt.Errorf("no parseable ReleaseTags in %v", tags) |
| } |
| |
| // GoVersionOutput returns the complete output of the go version command. |
| func GoVersionOutput(ctx context.Context, inv Invocation, r *Runner) (string, error) { |
| inv.Verb = "version" |
| goVersion, err := r.Run(ctx, inv) |
| if err != nil { |
| return "", err |
| } |
| return goVersion.String(), nil |
| } |
| |
| // ParseGoVersionOutput extracts the Go version string |
| // from the output of the "go version" command. |
| // Given an unrecognized form, it returns an empty string. |
| func ParseGoVersionOutput(data string) string { |
| re := regexp.MustCompile(`^go version (go\S+|devel \S+)`) |
| m := re.FindStringSubmatch(data) |
| if len(m) != 2 { |
| return "" // unrecognized version |
| } |
| return m[1] |
| } |