package gover
import (
- "cmp"
+ "internal/gover"
)
-// A version is a parsed Go version: major[.minor[.patch]][kind[pre]]
-// The numbers are the original decimal strings to avoid integer overflows
-// and since there is very little actual math. (Probably overflow doesn't matter in practice,
-// but at the time this code was written, there was an existing test that used
-// go1.99999999999, which does not fit in an int on 32-bit platforms.
-// The "big decimal" representation avoids the problem entirely.)
-type version struct {
- major string // decimal
- minor string // decimal or ""
- patch string // decimal or ""
- kind string // "", "alpha", "beta", "rc"
- pre string // decimal or ""
-}
-
// Compare returns -1, 0, or +1 depending on whether
// x < y, x == y, or x > y, interpreted as toolchain versions.
// The versions x and y must not begin with a "go" prefix: just "1.21" not "go1.21".
// Malformed versions compare less than well-formed versions and equal to each other.
// The language version "1.21" compares less than the release candidate and eventual releases "1.21rc1" and "1.21.0".
func Compare(x, y string) int {
- vx := parse(x)
- vy := parse(y)
-
- if c := cmpInt(vx.major, vy.major); c != 0 {
- return c
- }
- if c := cmpInt(vx.minor, vy.minor); c != 0 {
- return c
- }
- if c := cmpInt(vx.patch, vy.patch); c != 0 {
- return c
- }
- if c := cmp.Compare(vx.kind, vy.kind); c != 0 { // "" < alpha < beta < rc
- return c
- }
- if c := cmpInt(vx.pre, vy.pre); c != 0 {
- return c
- }
- return 0
+ return gover.Compare(x, y)
}
// Max returns the maximum of x and y interpreted as toolchain versions,
// compared using Compare.
// If x and y compare equal, Max returns x.
func Max(x, y string) string {
- if Compare(x, y) < 0 {
- return y
- }
- return x
-}
-
-// Toolchain returns the maximum of x and y interpreted as toolchain names,
-// compared using Compare(FromToolchain(x), FromToolchain(y)).
-// If x and y compare equal, Max returns x.
-func ToolchainMax(x, y string) string {
- if Compare(FromToolchain(x), FromToolchain(y)) < 0 {
- return y
- }
- return x
+ return gover.Max(x, y)
}
// IsLang reports whether v denotes the overall Go language version
// meaning that Go 1.21rc1 and Go 1.21.0 will both handle go.mod files that
// say "go 1.21", but Go 1.21rc1 will not handle files that say "go 1.21.0".
func IsLang(x string) bool {
- v := parse(x)
- return v != version{} && v.patch == "" && v.kind == "" && v.pre == ""
+ return gover.IsLang(x)
}
// Lang returns the Go language version. For example, Lang("1.2.3") == "1.2".
func Lang(x string) string {
- v := parse(x)
- if v.minor == "" {
- return v.major
- }
- return v.major + "." + v.minor
+ return gover.Lang(x)
}
// IsPrerelease reports whether v denotes a Go prerelease version.
func IsPrerelease(x string) bool {
- return parse(x).kind != ""
+ return gover.Parse(x).Kind != ""
}
// Prev returns the Go major release immediately preceding v,
// Prev("1.2") = "1.1"
// Prev("1.3rc4") = "1.2"
func Prev(x string) string {
- v := parse(x)
- if cmpInt(v.minor, "1") <= 0 {
- return v.major
+ v := gover.Parse(x)
+ if gover.CmpInt(v.Minor, "1") <= 0 {
+ return v.Major
}
- return v.major + "." + decInt(v.minor)
+ return v.Major + "." + gover.DecInt(v.Minor)
}
// IsValid reports whether the version x is valid.
func IsValid(x string) bool {
- return parse(x) != version{}
-}
-
-// parse parses the Go version string x into a version.
-// It returns the zero version if x is malformed.
-func parse(x string) version {
- var v version
-
- // Parse major version.
- var ok bool
- v.major, x, ok = cutInt(x)
- if !ok {
- return version{}
- }
- if x == "" {
- // Interpret "1" as "1.0.0".
- v.minor = "0"
- v.patch = "0"
- return v
- }
-
- // Parse . before minor version.
- if x[0] != '.' {
- return version{}
- }
-
- // Parse minor version.
- v.minor, x, ok = cutInt(x[1:])
- if !ok {
- return version{}
- }
- if x == "" {
- // Patch missing is same as "0" for older versions.
- // Starting in Go 1.21, patch missing is different from explicit .0.
- if cmpInt(v.minor, "21") < 0 {
- v.patch = "0"
- }
- return v
- }
-
- // Parse patch if present.
- if x[0] == '.' {
- v.patch, x, ok = cutInt(x[1:])
- if !ok || x != "" {
- // Note that we are disallowing prereleases (alpha, beta, rc) for patch releases here (x != "").
- // Allowing them would be a bit confusing because we already have:
- // 1.21 < 1.21rc1
- // But a prerelease of a patch would have the opposite effect:
- // 1.21.3rc1 < 1.21.3
- // We've never needed them before, so let's not start now.
- return version{}
- }
- return v
- }
-
- // Parse prerelease.
- i := 0
- for i < len(x) && (x[i] < '0' || '9' < x[i]) {
- if x[i] < 'a' || 'z' < x[i] {
- return version{}
- }
- i++
- }
- if i == 0 {
- return version{}
- }
- v.kind, x = x[:i], x[i:]
- if x == "" {
- return v
- }
- v.pre, x, ok = cutInt(x)
- if !ok || x != "" {
- return version{}
- }
-
- return v
-}
-
-// cutInt scans the leading decimal number at the start of x to an integer
-// and returns that value and the rest of the string.
-func cutInt(x string) (n, rest string, ok bool) {
- i := 0
- for i < len(x) && '0' <= x[i] && x[i] <= '9' {
- i++
- }
- if i == 0 || x[0] == '0' && i != 1 {
- return "", "", false
- }
- return x[:i], x[i:], true
-}
-
-// cmpInt returns cmp.Compare(x, y) interpreting x and y as decimal numbers.
-// (Copied from golang.org/x/mod/semver's compareInt.)
-func cmpInt(x, y string) int {
- if x == y {
- return 0
- }
- if len(x) < len(y) {
- return -1
- }
- if len(x) > len(y) {
- return +1
- }
- if x < y {
- return -1
- } else {
- return +1
- }
-}
-
-// decInt returns the decimal string decremented by 1, or the empty string
-// if the decimal is all zeroes.
-// (Copied from golang.org/x/mod/module's decDecimal.)
-func decInt(decimal string) string {
- // Scan right to left turning 0s to 9s until you find a digit to decrement.
- digits := []byte(decimal)
- i := len(digits) - 1
- for ; i >= 0 && digits[i] == '0'; i-- {
- digits[i] = '9'
- }
- if i < 0 {
- // decimal is all zeros
- return ""
- }
- if i == 0 && digits[i] == '1' && len(digits) > 1 {
- digits = digits[1:]
- } else {
- digits[i]--
- }
- return string(digits)
+ return gover.IsValid(x)
}