| // Copyright 2023 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 externalaccount |
| |
| import ( |
| "runtime" |
| "strings" |
| "unicode" |
| ) |
| |
| var ( |
| // version is a package internal global variable for testing purposes. |
| version = runtime.Version |
| ) |
| |
| // versionUnknown is only used when the runtime version cannot be determined. |
| const versionUnknown = "UNKNOWN" |
| |
| // goVersion returns a Go runtime version derived from the runtime environment |
| // that is modified to be suitable for reporting in a header, meaning it has no |
| // whitespace. If it is unable to determine the Go runtime version, it returns |
| // versionUnknown. |
| func goVersion() string { |
| const develPrefix = "devel +" |
| |
| s := version() |
| if strings.HasPrefix(s, develPrefix) { |
| s = s[len(develPrefix):] |
| if p := strings.IndexFunc(s, unicode.IsSpace); p >= 0 { |
| s = s[:p] |
| } |
| return s |
| } else if p := strings.IndexFunc(s, unicode.IsSpace); p >= 0 { |
| s = s[:p] |
| } |
| |
| notSemverRune := func(r rune) bool { |
| return !strings.ContainsRune("0123456789.", r) |
| } |
| |
| if strings.HasPrefix(s, "go1") { |
| s = s[2:] |
| var prerelease string |
| if p := strings.IndexFunc(s, notSemverRune); p >= 0 { |
| s, prerelease = s[:p], s[p:] |
| } |
| if strings.HasSuffix(s, ".") { |
| s += "0" |
| } else if strings.Count(s, ".") < 2 { |
| s += ".0" |
| } |
| if prerelease != "" { |
| // Some release candidates already have a dash in them. |
| if !strings.HasPrefix(prerelease, "-") { |
| prerelease = "-" + prerelease |
| } |
| s += prerelease |
| } |
| return s |
| } |
| return "UNKNOWN" |
| } |