cmd/go/internal/vcs: don’t new errors ahead of time in gitRemoteRepo

Also make 'cmd' a const for it is in fact immutable.

Change-Id: I3373daa1775e863a378355a355325a7fbdf90485
GitHub-Last-Rev: f669817
GitHub-Pull-Request: #63155
Reviewed-on: https://go-review.googlesource.com/c/go/+/530395
Auto-Submit: Bryan Mills <[email protected]>
LUCI-TryBot-Result: Go LUCI <[email protected]>
Reviewed-by: Than McIntosh <[email protected]>
Reviewed-by: Bryan Mills <[email protected]>

Author: callthingsoff

src/cmd/go/internal/vcs/vcs.go

@@ -283,15 +283,13 @@ var vcsGit = &Cmd{
 var scpSyntaxRe = lazyregexp.New(`^(\w+)@([\w.-]+):(.*)$`)
 
 func gitRemoteRepo(vcsGit *Cmd, rootDir string) (remoteRepo string, err error) {
-	cmd := "config remote.origin.url"
-	errParse := errors.New("unable to parse output of git " + cmd)
-	errRemoteOriginNotFound := errors.New("remote origin not found")
+	const cmd = "config remote.origin.url"
 	outb, err := vcsGit.run1(rootDir, cmd, nil, false)
 	if err != nil {
 		// if it doesn't output any message, it means the config argument is correct,
 		// but the config value itself doesn't exist
 		if outb != nil && len(outb) == 0 {
-			return "", errRemoteOriginNotFound
+			return "", errors.New("remote origin not found")
 		}
 		return "", err
 	}
@@ -323,7 +321,7 @@ func gitRemoteRepo(vcsGit *Cmd, rootDir string) (remoteRepo string, err error) {
 			return repoURL.String(), nil
 		}
 	}
-	return "", errParse
+	return "", errors.New("unable to parse output of git " + cmd)
 }
 
 func gitStatus(vcsGit *Cmd, rootDir string) (Status, error) {