Skip to content

docs: clarify Invalid Variant documentation and usage #231

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
AdamMagued wants to merge 1 commit into
base: master
Choose a base branch
from
Open

docs: clarify Invalid Variant documentation and usage #231

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
12 changes: 11 additions & 1 deletion uuid.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -23,9 +23,15 @@ type UUID [16]byte
type Version byte

// A Variant represents a UUID's variant.
//
// Any valid 128-bit UUID classifies into RFC4122, Reserved, Microsoft, or
// Future. Invalid represents an uninitialized or non-UUID sentinel.
type Variant byte

// Constants returned by Variant.
// Constants representing UUID variants.
//
// Any valid 128-bit UUID classifies into RFC4122, Reserved, Microsoft, or
// Future. Invalid represents an uninitialized or non-UUID sentinel.
const (
Invalid = Variant(iota) // Invalid UUID
RFC4122 // The variant specified in RFC9562(obsoletes RFC4122).
Expand Down Expand Up @@ -297,6 +303,10 @@ func encodeHex(dst []byte, uuid UUID) {
}

// Variant returns the variant encoded in uuid.
//
// Any valid 128-bit UUID classifies into RFC4122, Reserved, Microsoft, or
// Future. Variant never returns Invalid, which represents an uninitialized or
// non-UUID sentinel.
func (uuid UUID) Variant() Variant {
switch {
case (uuid[8] & 0xc0) == 0x80:
Expand Down
27 changes: 27 additions & 0 deletions uuid_test.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -60,6 +60,8 @@ var tests = []test{
{"f47ac10b-58cc-4372-e567-0e02b2c3d479", 4, Future, true},
{"f47ac10b-58cc-4372-f567-0e02b2c3d479", 4, Future, true},

// For invalid UUID strings, Parse returns an error and the test runner returns
// early without evaluating version or variant. Invalid is used as a placeholder.
{"f47ac10b158cc-5372-a567-0e02b2c3d479", 0, Invalid, false},
{"f47ac10b-58cc25372-a567-0e02b2c3d479", 0, Invalid, false},
{"f47ac10b-58cc-53723a567-0e02b2c3d479", 0, Invalid, false},
Expand Down Expand Up @@ -165,6 +167,31 @@ func TestConstants(t *testing.T) {
}
}

func TestVariantInvalid(t *testing.T) {
if s := Invalid.String(); s != "Invalid" {
t.Errorf("Invalid.String() = %q, want %q", s, "Invalid")
}
if s := Variant(0).String(); s != "Invalid" {
t.Errorf("Variant(0).String() = %q, want %q", s, "Invalid")
}
}

func TestVariantAllBytes(t *testing.T) {
for b := 0; b <= 0xff; b++ {
var u UUID
u[8] = byte(b)
v := u.Variant()
if v == Invalid {
t.Errorf("UUID with byte[8]=%#x returned Invalid variant", b)
}
switch v {
case RFC4122, Reserved, Microsoft, Future:
default:
t.Errorf("UUID with byte[8]=%#x returned unexpected variant %v", b, v)
}
}
}

func TestRandomUUID(t *testing.T) {
m := make(map[string]bool)
for x := 1; x < 32; x++ {
Expand Down
Loading