Update go dependencies (#4322)

This commit is contained in:
Manuel Alejandro de Brito Fontes 2019-07-17 09:21:14 -04:00 committed by GitHub
parent 28cc3bb5e2
commit a54ab3341e
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507 changed files with 50566 additions and 40414 deletions

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@ -22,7 +22,7 @@
// See some discussion on the matter here:
// http://google-opensource.blogspot.com/2013/01/c-containers-that-save-memory-and-time.html
// Note, though, that this project is in no way related to the C++ B-Tree
// implementation written about there.
// implmentation written about there.
//
// Within this tree, each node contains a slice of items and a (possibly nil)
// slice of children. For basic numeric values or raw structs, this can cause
@ -44,7 +44,7 @@
// widely used ordered tree implementation in the Go ecosystem currently.
// Its functions, therefore, exactly mirror those of
// llrb.LLRB where possible. Unlike gollrb, though, we currently don't
// support storing multiple equivalent values.
// support storing multiple equivalent values or backwards iteration.
package btree
import (
@ -52,7 +52,6 @@ import (
"io"
"sort"
"strings"
"sync"
)
// Item represents a single object in the tree.
@ -69,17 +68,11 @@ const (
DefaultFreeListSize = 32
)
var (
nilItems = make(items, 16)
nilChildren = make(children, 16)
)
// FreeList represents a free list of btree nodes. By default each
// BTree has its own FreeList, but multiple BTrees can share the same
// FreeList.
// Two Btrees using the same freelist are safe for concurrent write access.
// Two Btrees using the same freelist are not safe for concurrent write access.
type FreeList struct {
mu sync.Mutex
freelist []*node
}
@ -90,29 +83,18 @@ func NewFreeList(size int) *FreeList {
}
func (f *FreeList) newNode() (n *node) {
f.mu.Lock()
index := len(f.freelist) - 1
if index < 0 {
f.mu.Unlock()
return new(node)
}
n = f.freelist[index]
f.freelist[index] = nil
f.freelist = f.freelist[:index]
f.mu.Unlock()
f.freelist, n = f.freelist[:index], f.freelist[index]
return
}
// freeNode adds the given node to the list, returning true if it was added
// and false if it was discarded.
func (f *FreeList) freeNode(n *node) (out bool) {
f.mu.Lock()
func (f *FreeList) freeNode(n *node) {
if len(f.freelist) < cap(f.freelist) {
f.freelist = append(f.freelist, n)
out = true
}
f.mu.Unlock()
return
}
// ItemIterator allows callers of Ascend* to iterate in-order over portions of
@ -134,8 +116,8 @@ func NewWithFreeList(degree int, f *FreeList) *BTree {
panic("bad degree")
}
return &BTree{
degree: degree,
cow: &copyOnWriteContext{freelist: f},
degree: degree,
freelist: f,
}
}
@ -156,8 +138,8 @@ func (s *items) insertAt(index int, item Item) {
// back.
func (s *items) removeAt(index int) Item {
item := (*s)[index]
(*s)[index] = nil
copy((*s)[index:], (*s)[index+1:])
(*s)[len(*s)-1] = nil
*s = (*s)[:len(*s)-1]
return item
}
@ -171,16 +153,6 @@ func (s *items) pop() (out Item) {
return
}
// truncate truncates this instance at index so that it contains only the
// first index items. index must be less than or equal to length.
func (s *items) truncate(index int) {
var toClear items
*s, toClear = (*s)[:index], (*s)[index:]
for len(toClear) > 0 {
toClear = toClear[copy(toClear, nilItems):]
}
}
// find returns the index where the given item should be inserted into this
// list. 'found' is true if the item already exists in the list at the given
// index.
@ -211,8 +183,8 @@ func (s *children) insertAt(index int, n *node) {
// back.
func (s *children) removeAt(index int) *node {
n := (*s)[index]
(*s)[index] = nil
copy((*s)[index:], (*s)[index+1:])
(*s)[len(*s)-1] = nil
*s = (*s)[:len(*s)-1]
return n
}
@ -226,16 +198,6 @@ func (s *children) pop() (out *node) {
return
}
// truncate truncates this instance at index so that it contains only the
// first index children. index must be less than or equal to length.
func (s *children) truncate(index int) {
var toClear children
*s, toClear = (*s)[:index], (*s)[index:]
for len(toClear) > 0 {
toClear = toClear[copy(toClear, nilChildren):]
}
}
// node is an internal node in a tree.
//
// It must at all times maintain the invariant that either
@ -244,34 +206,7 @@ func (s *children) truncate(index int) {
type node struct {
items items
children children
cow *copyOnWriteContext
}
func (n *node) mutableFor(cow *copyOnWriteContext) *node {
if n.cow == cow {
return n
}
out := cow.newNode()
if cap(out.items) >= len(n.items) {
out.items = out.items[:len(n.items)]
} else {
out.items = make(items, len(n.items), cap(n.items))
}
copy(out.items, n.items)
// Copy children
if cap(out.children) >= len(n.children) {
out.children = out.children[:len(n.children)]
} else {
out.children = make(children, len(n.children), cap(n.children))
}
copy(out.children, n.children)
return out
}
func (n *node) mutableChild(i int) *node {
c := n.children[i].mutableFor(n.cow)
n.children[i] = c
return c
t *BTree
}
// split splits the given node at the given index. The current node shrinks,
@ -279,12 +214,12 @@ func (n *node) mutableChild(i int) *node {
// containing all items/children after it.
func (n *node) split(i int) (Item, *node) {
item := n.items[i]
next := n.cow.newNode()
next := n.t.newNode()
next.items = append(next.items, n.items[i+1:]...)
n.items.truncate(i)
n.items = n.items[:i]
if len(n.children) > 0 {
next.children = append(next.children, n.children[i+1:]...)
n.children.truncate(i + 1)
n.children = n.children[:i+1]
}
return item, next
}
@ -295,7 +230,7 @@ func (n *node) maybeSplitChild(i, maxItems int) bool {
if len(n.children[i].items) < maxItems {
return false
}
first := n.mutableChild(i)
first := n.children[i]
item, second := first.split(maxItems / 2)
n.items.insertAt(i, item)
n.children.insertAt(i+1, second)
@ -329,7 +264,7 @@ func (n *node) insert(item Item, maxItems int) Item {
return out
}
}
return n.mutableChild(i).insert(item, maxItems)
return n.children[i].insert(item, maxItems)
}
// get finds the given key in the subtree and returns it.
@ -407,10 +342,10 @@ func (n *node) remove(item Item, minItems int, typ toRemove) Item {
panic("invalid type")
}
// If we get to here, we have children.
if len(n.children[i].items) <= minItems {
child := n.children[i]
if len(child.items) <= minItems {
return n.growChildAndRemove(i, item, minItems, typ)
}
child := n.mutableChild(i)
// Either we had enough items to begin with, or we've done some
// merging/stealing, because we've got enough now and we're ready to return
// stuff.
@ -449,10 +384,10 @@ func (n *node) remove(item Item, minItems int, typ toRemove) Item {
// whether we're in case 1 or 2), we'll have enough items and can guarantee
// that we hit case A.
func (n *node) growChildAndRemove(i int, item Item, minItems int, typ toRemove) Item {
child := n.children[i]
if i > 0 && len(n.children[i-1].items) > minItems {
// Steal from left child
child := n.mutableChild(i)
stealFrom := n.mutableChild(i - 1)
stealFrom := n.children[i-1]
stolenItem := stealFrom.items.pop()
child.items.insertAt(0, n.items[i-1])
n.items[i-1] = stolenItem
@ -461,8 +396,7 @@ func (n *node) growChildAndRemove(i int, item Item, minItems int, typ toRemove)
}
} else if i < len(n.items) && len(n.children[i+1].items) > minItems {
// steal from right child
child := n.mutableChild(i)
stealFrom := n.mutableChild(i + 1)
stealFrom := n.children[i+1]
stolenItem := stealFrom.items.removeAt(0)
child.items = append(child.items, n.items[i])
n.items[i] = stolenItem
@ -472,99 +406,47 @@ func (n *node) growChildAndRemove(i int, item Item, minItems int, typ toRemove)
} else {
if i >= len(n.items) {
i--
child = n.children[i]
}
child := n.mutableChild(i)
// merge with right child
mergeItem := n.items.removeAt(i)
mergeChild := n.children.removeAt(i + 1)
child.items = append(child.items, mergeItem)
child.items = append(child.items, mergeChild.items...)
child.children = append(child.children, mergeChild.children...)
n.cow.freeNode(mergeChild)
n.t.freeNode(mergeChild)
}
return n.remove(item, minItems, typ)
}
type direction int
const (
descend = direction(-1)
ascend = direction(+1)
)
// iterate provides a simple method for iterating over elements in the tree.
// It could probably use some work to be extra-efficient (it calls from() a
// little more than it should), but it works pretty well for now.
//
// When ascending, the 'start' should be less than 'stop' and when descending,
// the 'start' should be greater than 'stop'. Setting 'includeStart' to true
// will force the iterator to include the first item when it equals 'start',
// thus creating a "greaterOrEqual" or "lessThanEqual" rather than just a
// "greaterThan" or "lessThan" queries.
func (n *node) iterate(dir direction, start, stop Item, includeStart bool, hit bool, iter ItemIterator) (bool, bool) {
var ok, found bool
var index int
switch dir {
case ascend:
if start != nil {
index, _ = n.items.find(start)
// It requires that 'from' and 'to' both return true for values we should hit
// with the iterator. It should also be the case that 'from' returns true for
// values less than or equal to values 'to' returns true for, and 'to'
// returns true for values greater than or equal to those that 'from'
// does.
func (n *node) iterate(from, to func(Item) bool, iter ItemIterator) bool {
for i, item := range n.items {
if !from(item) {
continue
}
for i := index; i < len(n.items); i++ {
if len(n.children) > 0 {
if hit, ok = n.children[i].iterate(dir, start, stop, includeStart, hit, iter); !ok {
return hit, false
}
}
if !includeStart && !hit && start != nil && !start.Less(n.items[i]) {
hit = true
continue
}
hit = true
if stop != nil && !n.items[i].Less(stop) {
return hit, false
}
if !iter(n.items[i]) {
return hit, false
}
if len(n.children) > 0 && !n.children[i].iterate(from, to, iter) {
return false
}
if len(n.children) > 0 {
if hit, ok = n.children[len(n.children)-1].iterate(dir, start, stop, includeStart, hit, iter); !ok {
return hit, false
}
if !to(item) {
return false
}
case descend:
if start != nil {
index, found = n.items.find(start)
if !found {
index = index - 1
}
} else {
index = len(n.items) - 1
}
for i := index; i >= 0; i-- {
if start != nil && !n.items[i].Less(start) {
if !includeStart || hit || start.Less(n.items[i]) {
continue
}
}
if len(n.children) > 0 {
if hit, ok = n.children[i+1].iterate(dir, start, stop, includeStart, hit, iter); !ok {
return hit, false
}
}
if stop != nil && !stop.Less(n.items[i]) {
return hit, false // continue
}
hit = true
if !iter(n.items[i]) {
return hit, false
}
}
if len(n.children) > 0 {
if hit, ok = n.children[0].iterate(dir, start, stop, includeStart, hit, iter); !ok {
return hit, false
}
if !iter(item) {
return false
}
}
return hit, true
if len(n.children) > 0 {
return n.children[len(n.children)-1].iterate(from, to, iter)
}
return true
}
// Used for testing/debugging purposes.
@ -583,54 +465,12 @@ func (n *node) print(w io.Writer, level int) {
// Write operations are not safe for concurrent mutation by multiple
// goroutines, but Read operations are.
type BTree struct {
degree int
length int
root *node
cow *copyOnWriteContext
}
// copyOnWriteContext pointers determine node ownership... a tree with a write
// context equivalent to a node's write context is allowed to modify that node.
// A tree whose write context does not match a node's is not allowed to modify
// it, and must create a new, writable copy (IE: it's a Clone).
//
// When doing any write operation, we maintain the invariant that the current
// node's context is equal to the context of the tree that requested the write.
// We do this by, before we descend into any node, creating a copy with the
// correct context if the contexts don't match.
//
// Since the node we're currently visiting on any write has the requesting
// tree's context, that node is modifiable in place. Children of that node may
// not share context, but before we descend into them, we'll make a mutable
// copy.
type copyOnWriteContext struct {
degree int
length int
root *node
freelist *FreeList
}
// Clone clones the btree, lazily. Clone should not be called concurrently,
// but the original tree (t) and the new tree (t2) can be used concurrently
// once the Clone call completes.
//
// The internal tree structure of b is marked read-only and shared between t and
// t2. Writes to both t and t2 use copy-on-write logic, creating new nodes
// whenever one of b's original nodes would have been modified. Read operations
// should have no performance degredation. Write operations for both t and t2
// will initially experience minor slow-downs caused by additional allocs and
// copies due to the aforementioned copy-on-write logic, but should converge to
// the original performance characteristics of the original tree.
func (t *BTree) Clone() (t2 *BTree) {
// Create two entirely new copy-on-write contexts.
// This operation effectively creates three trees:
// the original, shared nodes (old b.cow)
// the new b.cow nodes
// the new out.cow nodes
cow1, cow2 := *t.cow, *t.cow
out := *t
t.cow = &cow1
out.cow = &cow2
return &out
}
// maxItems returns the max number of items to allow per node.
func (t *BTree) maxItems() int {
return t.degree*2 - 1
@ -642,37 +482,23 @@ func (t *BTree) minItems() int {
return t.degree - 1
}
func (c *copyOnWriteContext) newNode() (n *node) {
n = c.freelist.newNode()
n.cow = c
func (t *BTree) newNode() (n *node) {
n = t.freelist.newNode()
n.t = t
return
}
type freeType int
const (
ftFreelistFull freeType = iota // node was freed (available for GC, not stored in freelist)
ftStored // node was stored in the freelist for later use
ftNotOwned // node was ignored by COW, since it's owned by another one
)
// freeNode frees a node within a given COW context, if it's owned by that
// context. It returns what happened to the node (see freeType const
// documentation).
func (c *copyOnWriteContext) freeNode(n *node) freeType {
if n.cow == c {
// clear to allow GC
n.items.truncate(0)
n.children.truncate(0)
n.cow = nil
if c.freelist.freeNode(n) {
return ftStored
} else {
return ftFreelistFull
}
} else {
return ftNotOwned
func (t *BTree) freeNode(n *node) {
for i := range n.items {
n.items[i] = nil // clear to allow GC
}
n.items = n.items[:0]
for i := range n.children {
n.children[i] = nil // clear to allow GC
}
n.children = n.children[:0]
n.t = nil // clear to allow GC
t.freelist.freeNode(n)
}
// ReplaceOrInsert adds the given item to the tree. If an item in the tree
@ -685,19 +511,16 @@ func (t *BTree) ReplaceOrInsert(item Item) Item {
panic("nil item being added to BTree")
}
if t.root == nil {
t.root = t.cow.newNode()
t.root = t.newNode()
t.root.items = append(t.root.items, item)
t.length++
return nil
} else {
t.root = t.root.mutableFor(t.cow)
if len(t.root.items) >= t.maxItems() {
item2, second := t.root.split(t.maxItems() / 2)
oldroot := t.root
t.root = t.cow.newNode()
t.root.items = append(t.root.items, item2)
t.root.children = append(t.root.children, oldroot, second)
}
} else if len(t.root.items) >= t.maxItems() {
item2, second := t.root.split(t.maxItems() / 2)
oldroot := t.root
t.root = t.newNode()
t.root.items = append(t.root.items, item2)
t.root.children = append(t.root.children, oldroot, second)
}
out := t.root.insert(item, t.maxItems())
if out == nil {
@ -728,12 +551,11 @@ func (t *BTree) deleteItem(item Item, typ toRemove) Item {
if t.root == nil || len(t.root.items) == 0 {
return nil
}
t.root = t.root.mutableFor(t.cow)
out := t.root.remove(item, t.minItems(), typ)
if len(t.root.items) == 0 && len(t.root.children) > 0 {
oldroot := t.root
t.root = t.root.children[0]
t.cow.freeNode(oldroot)
t.freeNode(oldroot)
}
if out != nil {
t.length--
@ -747,7 +569,10 @@ func (t *BTree) AscendRange(greaterOrEqual, lessThan Item, iterator ItemIterator
if t.root == nil {
return
}
t.root.iterate(ascend, greaterOrEqual, lessThan, true, false, iterator)
t.root.iterate(
func(a Item) bool { return !a.Less(greaterOrEqual) },
func(a Item) bool { return a.Less(lessThan) },
iterator)
}
// AscendLessThan calls the iterator for every value in the tree within the range
@ -756,7 +581,10 @@ func (t *BTree) AscendLessThan(pivot Item, iterator ItemIterator) {
if t.root == nil {
return
}
t.root.iterate(ascend, nil, pivot, false, false, iterator)
t.root.iterate(
func(a Item) bool { return true },
func(a Item) bool { return a.Less(pivot) },
iterator)
}
// AscendGreaterOrEqual calls the iterator for every value in the tree within
@ -765,7 +593,10 @@ func (t *BTree) AscendGreaterOrEqual(pivot Item, iterator ItemIterator) {
if t.root == nil {
return
}
t.root.iterate(ascend, pivot, nil, true, false, iterator)
t.root.iterate(
func(a Item) bool { return !a.Less(pivot) },
func(a Item) bool { return true },
iterator)
}
// Ascend calls the iterator for every value in the tree within the range
@ -774,43 +605,10 @@ func (t *BTree) Ascend(iterator ItemIterator) {
if t.root == nil {
return
}
t.root.iterate(ascend, nil, nil, false, false, iterator)
}
// DescendRange calls the iterator for every value in the tree within the range
// [lessOrEqual, greaterThan), until iterator returns false.
func (t *BTree) DescendRange(lessOrEqual, greaterThan Item, iterator ItemIterator) {
if t.root == nil {
return
}
t.root.iterate(descend, lessOrEqual, greaterThan, true, false, iterator)
}
// DescendLessOrEqual calls the iterator for every value in the tree within the range
// [pivot, first], until iterator returns false.
func (t *BTree) DescendLessOrEqual(pivot Item, iterator ItemIterator) {
if t.root == nil {
return
}
t.root.iterate(descend, pivot, nil, true, false, iterator)
}
// DescendGreaterThan calls the iterator for every value in the tree within
// the range (pivot, last], until iterator returns false.
func (t *BTree) DescendGreaterThan(pivot Item, iterator ItemIterator) {
if t.root == nil {
return
}
t.root.iterate(descend, nil, pivot, false, false, iterator)
}
// Descend calls the iterator for every value in the tree within the range
// [last, first], until iterator returns false.
func (t *BTree) Descend(iterator ItemIterator) {
if t.root == nil {
return
}
t.root.iterate(descend, nil, nil, false, false, iterator)
t.root.iterate(
func(a Item) bool { return true },
func(a Item) bool { return true },
iterator)
}
// Get looks for the key item in the tree, returning it. It returns nil if
@ -842,45 +640,6 @@ func (t *BTree) Len() int {
return t.length
}
// Clear removes all items from the btree. If addNodesToFreelist is true,
// t's nodes are added to its freelist as part of this call, until the freelist
// is full. Otherwise, the root node is simply dereferenced and the subtree
// left to Go's normal GC processes.
//
// This can be much faster
// than calling Delete on all elements, because that requires finding/removing
// each element in the tree and updating the tree accordingly. It also is
// somewhat faster than creating a new tree to replace the old one, because
// nodes from the old tree are reclaimed into the freelist for use by the new
// one, instead of being lost to the garbage collector.
//
// This call takes:
// O(1): when addNodesToFreelist is false, this is a single operation.
// O(1): when the freelist is already full, it breaks out immediately
// O(freelist size): when the freelist is empty and the nodes are all owned
// by this tree, nodes are added to the freelist until full.
// O(tree size): when all nodes are owned by another tree, all nodes are
// iterated over looking for nodes to add to the freelist, and due to
// ownership, none are.
func (t *BTree) Clear(addNodesToFreelist bool) {
if t.root != nil && addNodesToFreelist {
t.root.reset(t.cow)
}
t.root, t.length = nil, 0
}
// reset returns a subtree to the freelist. It breaks out immediately if the
// freelist is full, since the only benefit of iterating is to fill that
// freelist up. Returns true if parent reset call should continue.
func (n *node) reset(c *copyOnWriteContext) bool {
for _, child := range n.children {
if !child.reset(c) {
return false
}
}
return c.freeNode(n) != ftFreelistFull
}
// Int implements the Item interface for integers.
type Int int

1
vendor/github.com/google/uuid/go.mod generated vendored Normal file
View file

@ -0,0 +1 @@
module github.com/google/uuid

View file

@ -48,6 +48,7 @@ func setNodeInterface(name string) bool {
// does not specify a specific interface generate a random Node ID
// (section 4.1.6)
if name == "" {
ifname = "random"
randomBits(nodeID[:])
return true
}

View file

@ -1,4 +1,4 @@
// Copyright 2016 Google Inc. All rights reserved.
// Copyright 2018 Google Inc. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
@ -35,20 +35,43 @@ const (
var rander = rand.Reader // random function
// Parse decodes s into a UUID or returns an error. Both the UUID form of
// xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx and
// urn:uuid:xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx are decoded.
// Parse decodes s into a UUID or returns an error. Both the standard UUID
// forms of xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx and
// urn:uuid:xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx are decoded as well as the
// Microsoft encoding {xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx} and the raw hex
// encoding: xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx.
func Parse(s string) (UUID, error) {
var uuid UUID
if len(s) != 36 {
if len(s) != 36+9 {
return uuid, fmt.Errorf("invalid UUID length: %d", len(s))
}
switch len(s) {
// xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
case 36:
// urn:uuid:xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
case 36 + 9:
if strings.ToLower(s[:9]) != "urn:uuid:" {
return uuid, fmt.Errorf("invalid urn prefix: %q", s[:9])
}
s = s[9:]
// {xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx}
case 36 + 2:
s = s[1:]
// xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
case 32:
var ok bool
for i := range uuid {
uuid[i], ok = xtob(s[i*2], s[i*2+1])
if !ok {
return uuid, errors.New("invalid UUID format")
}
}
return uuid, nil
default:
return uuid, fmt.Errorf("invalid UUID length: %d", len(s))
}
// s is now at least 36 bytes long
// it must be of the form xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
if s[8] != '-' || s[13] != '-' || s[18] != '-' || s[23] != '-' {
return uuid, errors.New("invalid UUID format")
}
@ -70,15 +93,29 @@ func Parse(s string) (UUID, error) {
// ParseBytes is like Parse, except it parses a byte slice instead of a string.
func ParseBytes(b []byte) (UUID, error) {
var uuid UUID
if len(b) != 36 {
if len(b) != 36+9 {
return uuid, fmt.Errorf("invalid UUID length: %d", len(b))
}
switch len(b) {
case 36: // xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
case 36 + 9: // urn:uuid:xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
if !bytes.Equal(bytes.ToLower(b[:9]), []byte("urn:uuid:")) {
return uuid, fmt.Errorf("invalid urn prefix: %q", b[:9])
}
b = b[9:]
case 36 + 2: // {xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx}
b = b[1:]
case 32: // xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
var ok bool
for i := 0; i < 32; i += 2 {
uuid[i/2], ok = xtob(b[i], b[i+1])
if !ok {
return uuid, errors.New("invalid UUID format")
}
}
return uuid, nil
default:
return uuid, fmt.Errorf("invalid UUID length: %d", len(b))
}
// s is now at least 36 bytes long
// it must be of the form xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
if b[8] != '-' || b[13] != '-' || b[18] != '-' || b[23] != '-' {
return uuid, errors.New("invalid UUID format")
}
@ -97,6 +134,16 @@ func ParseBytes(b []byte) (UUID, error) {
return uuid, nil
}
// MustParse is like Parse but panics if the string cannot be parsed.
// It simplifies safe initialization of global variables holding compiled UUIDs.
func MustParse(s string) UUID {
uuid, err := Parse(s)
if err != nil {
panic(`uuid: Parse(` + s + `): ` + err.Error())
}
return uuid
}
// FromBytes creates a new UUID from a byte slice. Returns an error if the slice
// does not have a length of 16. The bytes are copied from the slice.
func FromBytes(b []byte) (uuid UUID, err error) {
@ -130,7 +177,7 @@ func (uuid UUID) URN() string {
}
func encodeHex(dst []byte, uuid UUID) {
hex.Encode(dst[:], uuid[:4])
hex.Encode(dst, uuid[:4])
dst[8] = '-'
hex.Encode(dst[9:13], uuid[4:6])
dst[13] = '-'