github.com/cockroachdb/tools@v0.0.0-20230222021103-a6d27438930d/internal/gocommand/version.go (about)

     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  // GoVersionOutput returns the complete output of the go version command.
    62  func GoVersionOutput(ctx context.Context, inv Invocation, r *Runner) (string, error) {
    63  	inv.Verb = "version"
    64  	goVersion, err := r.Run(ctx, inv)
    65  	if err != nil {
    66  		return "", err
    67  	}
    68  	return goVersion.String(), nil
    69  }
    70  
    71  // ParseGoVersionOutput extracts the Go version string
    72  // from the output of the "go version" command.
    73  // Given an unrecognized form, it returns an empty string.
    74  func ParseGoVersionOutput(data string) string {
    75  	re := regexp.MustCompile(`^go version (go\S+|devel \S+)`)
    76  	m := re.FindStringSubmatch(data)
    77  	if len(m) != 2 {
    78  		return "" // unrecognized version
    79  	}
    80  	return m[1]
    81  }