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-rw-r--r--vendor/golang.org/x/exp/slices/slices.go515
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diff --git a/vendor/golang.org/x/exp/slices/slices.go b/vendor/golang.org/x/exp/slices/slices.go
deleted file mode 100644
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--- a/vendor/golang.org/x/exp/slices/slices.go
+++ /dev/null
@@ -1,515 +0,0 @@
-// Copyright 2021 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 slices defines various functions useful with slices of any type.
-package slices
-
-import (
- "unsafe"
-
- "golang.org/x/exp/constraints"
-)
-
-// Equal reports whether two slices are equal: the same length and all
-// elements equal. If the lengths are different, Equal returns false.
-// Otherwise, the elements are compared in increasing index order, and the
-// comparison stops at the first unequal pair.
-// Floating point NaNs are not considered equal.
-func Equal[S ~[]E, E comparable](s1, s2 S) bool {
- if len(s1) != len(s2) {
- return false
- }
- for i := range s1 {
- if s1[i] != s2[i] {
- return false
- }
- }
- return true
-}
-
-// EqualFunc reports whether two slices are equal using an equality
-// function on each pair of elements. If the lengths are different,
-// EqualFunc returns false. Otherwise, the elements are compared in
-// increasing index order, and the comparison stops at the first index
-// for which eq returns false.
-func EqualFunc[S1 ~[]E1, S2 ~[]E2, E1, E2 any](s1 S1, s2 S2, eq func(E1, E2) bool) bool {
- if len(s1) != len(s2) {
- return false
- }
- for i, v1 := range s1 {
- v2 := s2[i]
- if !eq(v1, v2) {
- return false
- }
- }
- return true
-}
-
-// Compare compares the elements of s1 and s2, using [cmp.Compare] on each pair
-// of elements. The elements are compared sequentially, starting at index 0,
-// until one element is not equal to the other.
-// The result of comparing the first non-matching elements is returned.
-// If both slices are equal until one of them ends, the shorter slice is
-// considered less than the longer one.
-// The result is 0 if s1 == s2, -1 if s1 < s2, and +1 if s1 > s2.
-func Compare[S ~[]E, E constraints.Ordered](s1, s2 S) int {
- for i, v1 := range s1 {
- if i >= len(s2) {
- return +1
- }
- v2 := s2[i]
- if c := cmpCompare(v1, v2); c != 0 {
- return c
- }
- }
- if len(s1) < len(s2) {
- return -1
- }
- return 0
-}
-
-// CompareFunc is like [Compare] but uses a custom comparison function on each
-// pair of elements.
-// The result is the first non-zero result of cmp; if cmp always
-// returns 0 the result is 0 if len(s1) == len(s2), -1 if len(s1) < len(s2),
-// and +1 if len(s1) > len(s2).
-func CompareFunc[S1 ~[]E1, S2 ~[]E2, E1, E2 any](s1 S1, s2 S2, cmp func(E1, E2) int) int {
- for i, v1 := range s1 {
- if i >= len(s2) {
- return +1
- }
- v2 := s2[i]
- if c := cmp(v1, v2); c != 0 {
- return c
- }
- }
- if len(s1) < len(s2) {
- return -1
- }
- return 0
-}
-
-// Index returns the index of the first occurrence of v in s,
-// or -1 if not present.
-func Index[S ~[]E, E comparable](s S, v E) int {
- for i := range s {
- if v == s[i] {
- return i
- }
- }
- return -1
-}
-
-// IndexFunc returns the first index i satisfying f(s[i]),
-// or -1 if none do.
-func IndexFunc[S ~[]E, E any](s S, f func(E) bool) int {
- for i := range s {
- if f(s[i]) {
- return i
- }
- }
- return -1
-}
-
-// Contains reports whether v is present in s.
-func Contains[S ~[]E, E comparable](s S, v E) bool {
- return Index(s, v) >= 0
-}
-
-// ContainsFunc reports whether at least one
-// element e of s satisfies f(e).
-func ContainsFunc[S ~[]E, E any](s S, f func(E) bool) bool {
- return IndexFunc(s, f) >= 0
-}
-
-// Insert inserts the values v... into s at index i,
-// returning the modified slice.
-// The elements at s[i:] are shifted up to make room.
-// In the returned slice r, r[i] == v[0],
-// and r[i+len(v)] == value originally at r[i].
-// Insert panics if i is out of range.
-// This function is O(len(s) + len(v)).
-func Insert[S ~[]E, E any](s S, i int, v ...E) S {
- m := len(v)
- if m == 0 {
- return s
- }
- n := len(s)
- if i == n {
- return append(s, v...)
- }
- if n+m > cap(s) {
- // Use append rather than make so that we bump the size of
- // the slice up to the next storage class.
- // This is what Grow does but we don't call Grow because
- // that might copy the values twice.
- s2 := append(s[:i], make(S, n+m-i)...)
- copy(s2[i:], v)
- copy(s2[i+m:], s[i:])
- return s2
- }
- s = s[:n+m]
-
- // before:
- // s: aaaaaaaabbbbccccccccdddd
- // ^ ^ ^ ^
- // i i+m n n+m
- // after:
- // s: aaaaaaaavvvvbbbbcccccccc
- // ^ ^ ^ ^
- // i i+m n n+m
- //
- // a are the values that don't move in s.
- // v are the values copied in from v.
- // b and c are the values from s that are shifted up in index.
- // d are the values that get overwritten, never to be seen again.
-
- if !overlaps(v, s[i+m:]) {
- // Easy case - v does not overlap either the c or d regions.
- // (It might be in some of a or b, or elsewhere entirely.)
- // The data we copy up doesn't write to v at all, so just do it.
-
- copy(s[i+m:], s[i:])
-
- // Now we have
- // s: aaaaaaaabbbbbbbbcccccccc
- // ^ ^ ^ ^
- // i i+m n n+m
- // Note the b values are duplicated.
-
- copy(s[i:], v)
-
- // Now we have
- // s: aaaaaaaavvvvbbbbcccccccc
- // ^ ^ ^ ^
- // i i+m n n+m
- // That's the result we want.
- return s
- }
-
- // The hard case - v overlaps c or d. We can't just shift up
- // the data because we'd move or clobber the values we're trying
- // to insert.
- // So instead, write v on top of d, then rotate.
- copy(s[n:], v)
-
- // Now we have
- // s: aaaaaaaabbbbccccccccvvvv
- // ^ ^ ^ ^
- // i i+m n n+m
-
- rotateRight(s[i:], m)
-
- // Now we have
- // s: aaaaaaaavvvvbbbbcccccccc
- // ^ ^ ^ ^
- // i i+m n n+m
- // That's the result we want.
- return s
-}
-
-// clearSlice sets all elements up to the length of s to the zero value of E.
-// We may use the builtin clear func instead, and remove clearSlice, when upgrading
-// to Go 1.21+.
-func clearSlice[S ~[]E, E any](s S) {
- var zero E
- for i := range s {
- s[i] = zero
- }
-}
-
-// Delete removes the elements s[i:j] from s, returning the modified slice.
-// Delete panics if j > len(s) or s[i:j] is not a valid slice of s.
-// Delete is O(len(s)-i), so if many items must be deleted, it is better to
-// make a single call deleting them all together than to delete one at a time.
-// Delete zeroes the elements s[len(s)-(j-i):len(s)].
-func Delete[S ~[]E, E any](s S, i, j int) S {
- _ = s[i:j:len(s)] // bounds check
-
- if i == j {
- return s
- }
-
- oldlen := len(s)
- s = append(s[:i], s[j:]...)
- clearSlice(s[len(s):oldlen]) // zero/nil out the obsolete elements, for GC
- return s
-}
-
-// DeleteFunc removes any elements from s for which del returns true,
-// returning the modified slice.
-// DeleteFunc zeroes the elements between the new length and the original length.
-func DeleteFunc[S ~[]E, E any](s S, del func(E) bool) S {
- i := IndexFunc(s, del)
- if i == -1 {
- return s
- }
- // Don't start copying elements until we find one to delete.
- for j := i + 1; j < len(s); j++ {
- if v := s[j]; !del(v) {
- s[i] = v
- i++
- }
- }
- clearSlice(s[i:]) // zero/nil out the obsolete elements, for GC
- return s[:i]
-}
-
-// Replace replaces the elements s[i:j] by the given v, and returns the
-// modified slice. Replace panics if s[i:j] is not a valid slice of s.
-// When len(v) < (j-i), Replace zeroes the elements between the new length and the original length.
-func Replace[S ~[]E, E any](s S, i, j int, v ...E) S {
- _ = s[i:j] // verify that i:j is a valid subslice
-
- if i == j {
- return Insert(s, i, v...)
- }
- if j == len(s) {
- return append(s[:i], v...)
- }
-
- tot := len(s[:i]) + len(v) + len(s[j:])
- if tot > cap(s) {
- // Too big to fit, allocate and copy over.
- s2 := append(s[:i], make(S, tot-i)...) // See Insert
- copy(s2[i:], v)
- copy(s2[i+len(v):], s[j:])
- return s2
- }
-
- r := s[:tot]
-
- if i+len(v) <= j {
- // Easy, as v fits in the deleted portion.
- copy(r[i:], v)
- if i+len(v) != j {
- copy(r[i+len(v):], s[j:])
- }
- clearSlice(s[tot:]) // zero/nil out the obsolete elements, for GC
- return r
- }
-
- // We are expanding (v is bigger than j-i).
- // The situation is something like this:
- // (example has i=4,j=8,len(s)=16,len(v)=6)
- // s: aaaaxxxxbbbbbbbbyy
- // ^ ^ ^ ^
- // i j len(s) tot
- // a: prefix of s
- // x: deleted range
- // b: more of s
- // y: area to expand into
-
- if !overlaps(r[i+len(v):], v) {
- // Easy, as v is not clobbered by the first copy.
- copy(r[i+len(v):], s[j:])
- copy(r[i:], v)
- return r
- }
-
- // This is a situation where we don't have a single place to which
- // we can copy v. Parts of it need to go to two different places.
- // We want to copy the prefix of v into y and the suffix into x, then
- // rotate |y| spots to the right.
- //
- // v[2:] v[:2]
- // | |
- // s: aaaavvvvbbbbbbbbvv
- // ^ ^ ^ ^
- // i j len(s) tot
- //
- // If either of those two destinations don't alias v, then we're good.
- y := len(v) - (j - i) // length of y portion
-
- if !overlaps(r[i:j], v) {
- copy(r[i:j], v[y:])
- copy(r[len(s):], v[:y])
- rotateRight(r[i:], y)
- return r
- }
- if !overlaps(r[len(s):], v) {
- copy(r[len(s):], v[:y])
- copy(r[i:j], v[y:])
- rotateRight(r[i:], y)
- return r
- }
-
- // Now we know that v overlaps both x and y.
- // That means that the entirety of b is *inside* v.
- // So we don't need to preserve b at all; instead we
- // can copy v first, then copy the b part of v out of
- // v to the right destination.
- k := startIdx(v, s[j:])
- copy(r[i:], v)
- copy(r[i+len(v):], r[i+k:])
- return r
-}
-
-// Clone returns a copy of the slice.
-// The elements are copied using assignment, so this is a shallow clone.
-func Clone[S ~[]E, E any](s S) S {
- // Preserve nil in case it matters.
- if s == nil {
- return nil
- }
- return append(S([]E{}), s...)
-}
-
-// Compact replaces consecutive runs of equal elements with a single copy.
-// This is like the uniq command found on Unix.
-// Compact modifies the contents of the slice s and returns the modified slice,
-// which may have a smaller length.
-// Compact zeroes the elements between the new length and the original length.
-func Compact[S ~[]E, E comparable](s S) S {
- if len(s) < 2 {
- return s
- }
- i := 1
- for k := 1; k < len(s); k++ {
- if s[k] != s[k-1] {
- if i != k {
- s[i] = s[k]
- }
- i++
- }
- }
- clearSlice(s[i:]) // zero/nil out the obsolete elements, for GC
- return s[:i]
-}
-
-// CompactFunc is like [Compact] but uses an equality function to compare elements.
-// For runs of elements that compare equal, CompactFunc keeps the first one.
-// CompactFunc zeroes the elements between the new length and the original length.
-func CompactFunc[S ~[]E, E any](s S, eq func(E, E) bool) S {
- if len(s) < 2 {
- return s
- }
- i := 1
- for k := 1; k < len(s); k++ {
- if !eq(s[k], s[k-1]) {
- if i != k {
- s[i] = s[k]
- }
- i++
- }
- }
- clearSlice(s[i:]) // zero/nil out the obsolete elements, for GC
- return s[:i]
-}
-
-// Grow increases the slice's capacity, if necessary, to guarantee space for
-// another n elements. After Grow(n), at least n elements can be appended
-// to the slice without another allocation. If n is negative or too large to
-// allocate the memory, Grow panics.
-func Grow[S ~[]E, E any](s S, n int) S {
- if n < 0 {
- panic("cannot be negative")
- }
- if n -= cap(s) - len(s); n > 0 {
- // TODO(https://go.dev/issue/53888): Make using []E instead of S
- // to workaround a compiler bug where the runtime.growslice optimization
- // does not take effect. Revert when the compiler is fixed.
- s = append([]E(s)[:cap(s)], make([]E, n)...)[:len(s)]
- }
- return s
-}
-
-// Clip removes unused capacity from the slice, returning s[:len(s):len(s)].
-func Clip[S ~[]E, E any](s S) S {
- return s[:len(s):len(s)]
-}
-
-// Rotation algorithm explanation:
-//
-// rotate left by 2
-// start with
-// 0123456789
-// split up like this
-// 01 234567 89
-// swap first 2 and last 2
-// 89 234567 01
-// join first parts
-// 89234567 01
-// recursively rotate first left part by 2
-// 23456789 01
-// join at the end
-// 2345678901
-//
-// rotate left by 8
-// start with
-// 0123456789
-// split up like this
-// 01 234567 89
-// swap first 2 and last 2
-// 89 234567 01
-// join last parts
-// 89 23456701
-// recursively rotate second part left by 6
-// 89 01234567
-// join at the end
-// 8901234567
-
-// TODO: There are other rotate algorithms.
-// This algorithm has the desirable property that it moves each element exactly twice.
-// The triple-reverse algorithm is simpler and more cache friendly, but takes more writes.
-// The follow-cycles algorithm can be 1-write but it is not very cache friendly.
-
-// rotateLeft rotates b left by n spaces.
-// s_final[i] = s_orig[i+r], wrapping around.
-func rotateLeft[E any](s []E, r int) {
- for r != 0 && r != len(s) {
- if r*2 <= len(s) {
- swap(s[:r], s[len(s)-r:])
- s = s[:len(s)-r]
- } else {
- swap(s[:len(s)-r], s[r:])
- s, r = s[len(s)-r:], r*2-len(s)
- }
- }
-}
-func rotateRight[E any](s []E, r int) {
- rotateLeft(s, len(s)-r)
-}
-
-// swap swaps the contents of x and y. x and y must be equal length and disjoint.
-func swap[E any](x, y []E) {
- for i := 0; i < len(x); i++ {
- x[i], y[i] = y[i], x[i]
- }
-}
-
-// overlaps reports whether the memory ranges a[0:len(a)] and b[0:len(b)] overlap.
-func overlaps[E any](a, b []E) bool {
- if len(a) == 0 || len(b) == 0 {
- return false
- }
- elemSize := unsafe.Sizeof(a[0])
- if elemSize == 0 {
- return false
- }
- // TODO: use a runtime/unsafe facility once one becomes available. See issue 12445.
- // Also see crypto/internal/alias/alias.go:AnyOverlap
- return uintptr(unsafe.Pointer(&a[0])) <= uintptr(unsafe.Pointer(&b[len(b)-1]))+(elemSize-1) &&
- uintptr(unsafe.Pointer(&b[0])) <= uintptr(unsafe.Pointer(&a[len(a)-1]))+(elemSize-1)
-}
-
-// startIdx returns the index in haystack where the needle starts.
-// prerequisite: the needle must be aliased entirely inside the haystack.
-func startIdx[E any](haystack, needle []E) int {
- p := &needle[0]
- for i := range haystack {
- if p == &haystack[i] {
- return i
- }
- }
- // TODO: what if the overlap is by a non-integral number of Es?
- panic("needle not found")
-}
-
-// Reverse reverses the elements of the slice in place.
-func Reverse[S ~[]E, E any](s S) {
- for i, j := 0, len(s)-1; i < j; i, j = i+1, j-1 {
- s[i], s[j] = s[j], s[i]
- }
-}