diff --git a/bot/command.go b/bot/command.go index 58f9318..0973b9f 100644 --- a/bot/command.go +++ b/bot/command.go @@ -424,6 +424,29 @@ func (b *Bot) sendIntroduction(ctx context.Context, roomID id.RoomID) { b.SendNotice(ctx, roomID, msg.String()) } +func (b *Bot) getHelpValue(cfg config.Room, cmd command) string { + name := cmd.key + if name == commandSpamlist { + name = config.RoomSpamlist + } + + value := cfg.Get(name) + if cmd.sanitizer != nil { + switch value != "" { + case false: + return "(currently not set)" + case true: + txt := "(currently " + value + if cmd.key == config.RoomMailbox { + txt += " (" + utils.EmailsList(value, cfg.Domain()) + ")" + } + return txt + ")" + } + } + + return "" +} + func (b *Bot) sendHelp(ctx context.Context) { evt := eventFromContext(ctx) @@ -451,27 +474,7 @@ func (b *Bot) sendHelp(ctx context.Context) { msg.WriteString(cmd.key) msg.WriteString("`**") - name := cmd.key - if name == commandSpamlist { - name = config.RoomSpamlist - } - value := cfg.Get(name) - if cmd.sanitizer != nil { - switch value != "" { - case false: - msg.WriteString("(currently not set)") - case true: - msg.WriteString("(currently `") - msg.WriteString(value) - if cmd.key == config.RoomMailbox { - msg.WriteString(" (") - msg.WriteString(utils.EmailsList(value, cfg.Domain())) - msg.WriteString(")") - } - msg.WriteString("`)") - } - } - + msg.WriteString(b.getHelpValue(cfg, cmd)) msg.WriteString(" - ") msg.WriteString(cmd.description) diff --git a/bot/command_owner.go b/bot/command_owner.go index ef4462c..e79b3bd 100644 --- a/bot/command_owner.go +++ b/bot/command_owner.go @@ -3,11 +3,11 @@ package bot import ( "context" "fmt" - "slices" "strconv" "strings" "github.com/raja/argon2pw" + "golang.org/x/exp/slices" "gitlab.com/etke.cc/postmoogle/bot/config" "gitlab.com/etke.cc/postmoogle/utils" diff --git a/go.mod b/go.mod index a7a1e40..484e132 100644 --- a/go.mod +++ b/go.mod @@ -26,6 +26,7 @@ require ( gitlab.com/etke.cc/go/trysmtp v1.1.3 gitlab.com/etke.cc/go/validator v1.0.6 gitlab.com/etke.cc/linkpearl v0.0.0-20230920071429-25fe33ba08d0 + golang.org/x/exp v0.0.0-20230905200255-921286631fa9 maunium.net/go/mautrix v0.16.1 ) @@ -52,7 +53,6 @@ require ( github.com/yuin/goldmark v1.5.6 // indirect go.mau.fi/util v0.1.0 // indirect golang.org/x/crypto v0.13.0 // indirect - golang.org/x/exp v0.0.0-20230905200255-921286631fa9 // indirect golang.org/x/net v0.15.0 // indirect golang.org/x/sys v0.12.0 // indirect golang.org/x/text v0.13.0 // indirect diff --git a/vendor/golang.org/x/exp/constraints/constraints.go b/vendor/golang.org/x/exp/constraints/constraints.go new file mode 100644 index 0000000..2c033df --- /dev/null +++ b/vendor/golang.org/x/exp/constraints/constraints.go @@ -0,0 +1,50 @@ +// 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 constraints defines a set of useful constraints to be used +// with type parameters. +package constraints + +// Signed is a constraint that permits any signed integer type. +// If future releases of Go add new predeclared signed integer types, +// this constraint will be modified to include them. +type Signed interface { + ~int | ~int8 | ~int16 | ~int32 | ~int64 +} + +// Unsigned is a constraint that permits any unsigned integer type. +// If future releases of Go add new predeclared unsigned integer types, +// this constraint will be modified to include them. +type Unsigned interface { + ~uint | ~uint8 | ~uint16 | ~uint32 | ~uint64 | ~uintptr +} + +// Integer is a constraint that permits any integer type. +// If future releases of Go add new predeclared integer types, +// this constraint will be modified to include them. +type Integer interface { + Signed | Unsigned +} + +// Float is a constraint that permits any floating-point type. +// If future releases of Go add new predeclared floating-point types, +// this constraint will be modified to include them. +type Float interface { + ~float32 | ~float64 +} + +// Complex is a constraint that permits any complex numeric type. +// If future releases of Go add new predeclared complex numeric types, +// this constraint will be modified to include them. +type Complex interface { + ~complex64 | ~complex128 +} + +// Ordered is a constraint that permits any ordered type: any type +// that supports the operators < <= >= >. +// If future releases of Go add new ordered types, +// this constraint will be modified to include them. +type Ordered interface { + Integer | Float | ~string +} diff --git a/vendor/golang.org/x/exp/slices/cmp.go b/vendor/golang.org/x/exp/slices/cmp.go new file mode 100644 index 0000000..fbf1934 --- /dev/null +++ b/vendor/golang.org/x/exp/slices/cmp.go @@ -0,0 +1,44 @@ +// 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 slices + +import "golang.org/x/exp/constraints" + +// min is a version of the predeclared function from the Go 1.21 release. +func min[T constraints.Ordered](a, b T) T { + if a < b || isNaN(a) { + return a + } + return b +} + +// max is a version of the predeclared function from the Go 1.21 release. +func max[T constraints.Ordered](a, b T) T { + if a > b || isNaN(a) { + return a + } + return b +} + +// cmpLess is a copy of cmp.Less from the Go 1.21 release. +func cmpLess[T constraints.Ordered](x, y T) bool { + return (isNaN(x) && !isNaN(y)) || x < y +} + +// cmpCompare is a copy of cmp.Compare from the Go 1.21 release. +func cmpCompare[T constraints.Ordered](x, y T) int { + xNaN := isNaN(x) + yNaN := isNaN(y) + if xNaN && yNaN { + return 0 + } + if xNaN || x < y { + return -1 + } + if yNaN || x > y { + return +1 + } + return 0 +} diff --git a/vendor/golang.org/x/exp/slices/slices.go b/vendor/golang.org/x/exp/slices/slices.go new file mode 100644 index 0000000..5e8158b --- /dev/null +++ b/vendor/golang.org/x/exp/slices/slices.go @@ -0,0 +1,499 @@ +// 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 +} + +// Delete removes the elements s[i:j] from s, returning the modified slice. +// Delete panics if s[i:j] is not a valid slice of s. +// Delete is O(len(s)-j), 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 might not modify the elements s[len(s)-(j-i):len(s)]. If those +// elements contain pointers you might consider zeroing those elements so that +// objects they reference can be garbage collected. +func Delete[S ~[]E, E any](s S, i, j int) S { + _ = s[i:j] // bounds check + + return append(s[:i], s[j:]...) +} + +// DeleteFunc removes any elements from s for which del returns true, +// returning the modified slice. +// When DeleteFunc removes m elements, it might not modify the elements +// s[len(s)-m:len(s)]. If those elements contain pointers you might consider +// zeroing those elements so that objects they reference can be garbage +// collected. +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++ + } + } + 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. +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:]) + } + 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. +// When Compact discards m elements in total, it might not modify the elements +// s[len(s)-m:len(s)]. If those elements contain pointers you might consider +// zeroing those elements so that objects they reference can be garbage collected. +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++ + } + } + 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. +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++ + } + } + 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] + } +} diff --git a/vendor/golang.org/x/exp/slices/sort.go b/vendor/golang.org/x/exp/slices/sort.go new file mode 100644 index 0000000..b67897f --- /dev/null +++ b/vendor/golang.org/x/exp/slices/sort.go @@ -0,0 +1,195 @@ +// Copyright 2022 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. + +//go:generate go run $GOROOT/src/sort/gen_sort_variants.go -exp + +package slices + +import ( + "math/bits" + + "golang.org/x/exp/constraints" +) + +// Sort sorts a slice of any ordered type in ascending order. +// When sorting floating-point numbers, NaNs are ordered before other values. +func Sort[S ~[]E, E constraints.Ordered](x S) { + n := len(x) + pdqsortOrdered(x, 0, n, bits.Len(uint(n))) +} + +// SortFunc sorts the slice x in ascending order as determined by the cmp +// function. This sort is not guaranteed to be stable. +// cmp(a, b) should return a negative number when a < b, a positive number when +// a > b and zero when a == b. +// +// SortFunc requires that cmp is a strict weak ordering. +// See https://en.wikipedia.org/wiki/Weak_ordering#Strict_weak_orderings. +func SortFunc[S ~[]E, E any](x S, cmp func(a, b E) int) { + n := len(x) + pdqsortCmpFunc(x, 0, n, bits.Len(uint(n)), cmp) +} + +// SortStableFunc sorts the slice x while keeping the original order of equal +// elements, using cmp to compare elements in the same way as [SortFunc]. +func SortStableFunc[S ~[]E, E any](x S, cmp func(a, b E) int) { + stableCmpFunc(x, len(x), cmp) +} + +// IsSorted reports whether x is sorted in ascending order. +func IsSorted[S ~[]E, E constraints.Ordered](x S) bool { + for i := len(x) - 1; i > 0; i-- { + if cmpLess(x[i], x[i-1]) { + return false + } + } + return true +} + +// IsSortedFunc reports whether x is sorted in ascending order, with cmp as the +// comparison function as defined by [SortFunc]. +func IsSortedFunc[S ~[]E, E any](x S, cmp func(a, b E) int) bool { + for i := len(x) - 1; i > 0; i-- { + if cmp(x[i], x[i-1]) < 0 { + return false + } + } + return true +} + +// Min returns the minimal value in x. It panics if x is empty. +// For floating-point numbers, Min propagates NaNs (any NaN value in x +// forces the output to be NaN). +func Min[S ~[]E, E constraints.Ordered](x S) E { + if len(x) < 1 { + panic("slices.Min: empty list") + } + m := x[0] + for i := 1; i < len(x); i++ { + m = min(m, x[i]) + } + return m +} + +// MinFunc returns the minimal value in x, using cmp to compare elements. +// It panics if x is empty. If there is more than one minimal element +// according to the cmp function, MinFunc returns the first one. +func MinFunc[S ~[]E, E any](x S, cmp func(a, b E) int) E { + if len(x) < 1 { + panic("slices.MinFunc: empty list") + } + m := x[0] + for i := 1; i < len(x); i++ { + if cmp(x[i], m) < 0 { + m = x[i] + } + } + return m +} + +// Max returns the maximal value in x. It panics if x is empty. +// For floating-point E, Max propagates NaNs (any NaN value in x +// forces the output to be NaN). +func Max[S ~[]E, E constraints.Ordered](x S) E { + if len(x) < 1 { + panic("slices.Max: empty list") + } + m := x[0] + for i := 1; i < len(x); i++ { + m = max(m, x[i]) + } + return m +} + +// MaxFunc returns the maximal value in x, using cmp to compare elements. +// It panics if x is empty. If there is more than one maximal element +// according to the cmp function, MaxFunc returns the first one. +func MaxFunc[S ~[]E, E any](x S, cmp func(a, b E) int) E { + if len(x) < 1 { + panic("slices.MaxFunc: empty list") + } + m := x[0] + for i := 1; i < len(x); i++ { + if cmp(x[i], m) > 0 { + m = x[i] + } + } + return m +} + +// BinarySearch searches for target in a sorted slice and returns the position +// where target is found, or the position where target would appear in the +// sort order; it also returns a bool saying whether the target is really found +// in the slice. The slice must be sorted in increasing order. +func BinarySearch[S ~[]E, E constraints.Ordered](x S, target E) (int, bool) { + // Inlining is faster than calling BinarySearchFunc with a lambda. + n := len(x) + // Define x[-1] < target and x[n] >= target. + // Invariant: x[i-1] < target, x[j] >= target. + i, j := 0, n + for i < j { + h := int(uint(i+j) >> 1) // avoid overflow when computing h + // i ≤ h < j + if cmpLess(x[h], target) { + i = h + 1 // preserves x[i-1] < target + } else { + j = h // preserves x[j] >= target + } + } + // i == j, x[i-1] < target, and x[j] (= x[i]) >= target => answer is i. + return i, i < n && (x[i] == target || (isNaN(x[i]) && isNaN(target))) +} + +// BinarySearchFunc works like [BinarySearch], but uses a custom comparison +// function. The slice must be sorted in increasing order, where "increasing" +// is defined by cmp. cmp should return 0 if the slice element matches +// the target, a negative number if the slice element precedes the target, +// or a positive number if the slice element follows the target. +// cmp must implement the same ordering as the slice, such that if +// cmp(a, t) < 0 and cmp(b, t) >= 0, then a must precede b in the slice. +func BinarySearchFunc[S ~[]E, E, T any](x S, target T, cmp func(E, T) int) (int, bool) { + n := len(x) + // Define cmp(x[-1], target) < 0 and cmp(x[n], target) >= 0 . + // Invariant: cmp(x[i - 1], target) < 0, cmp(x[j], target) >= 0. + i, j := 0, n + for i < j { + h := int(uint(i+j) >> 1) // avoid overflow when computing h + // i ≤ h < j + if cmp(x[h], target) < 0 { + i = h + 1 // preserves cmp(x[i - 1], target) < 0 + } else { + j = h // preserves cmp(x[j], target) >= 0 + } + } + // i == j, cmp(x[i-1], target) < 0, and cmp(x[j], target) (= cmp(x[i], target)) >= 0 => answer is i. + return i, i < n && cmp(x[i], target) == 0 +} + +type sortedHint int // hint for pdqsort when choosing the pivot + +const ( + unknownHint sortedHint = iota + increasingHint + decreasingHint +) + +// xorshift paper: https://www.jstatsoft.org/article/view/v008i14/xorshift.pdf +type xorshift uint64 + +func (r *xorshift) Next() uint64 { + *r ^= *r << 13 + *r ^= *r >> 17 + *r ^= *r << 5 + return uint64(*r) +} + +func nextPowerOfTwo(length int) uint { + return 1 << bits.Len(uint(length)) +} + +// isNaN reports whether x is a NaN without requiring the math package. +// This will always return false if T is not floating-point. +func isNaN[T constraints.Ordered](x T) bool { + return x != x +} diff --git a/vendor/golang.org/x/exp/slices/zsortanyfunc.go b/vendor/golang.org/x/exp/slices/zsortanyfunc.go new file mode 100644 index 0000000..06f2c7a --- /dev/null +++ b/vendor/golang.org/x/exp/slices/zsortanyfunc.go @@ -0,0 +1,479 @@ +// Code generated by gen_sort_variants.go; DO NOT EDIT. + +// Copyright 2022 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 + +// insertionSortCmpFunc sorts data[a:b] using insertion sort. +func insertionSortCmpFunc[E any](data []E, a, b int, cmp func(a, b E) int) { + for i := a + 1; i < b; i++ { + for j := i; j > a && (cmp(data[j], data[j-1]) < 0); j-- { + data[j], data[j-1] = data[j-1], data[j] + } + } +} + +// siftDownCmpFunc implements the heap property on data[lo:hi]. +// first is an offset into the array where the root of the heap lies. +func siftDownCmpFunc[E any](data []E, lo, hi, first int, cmp func(a, b E) int) { + root := lo + for { + child := 2*root + 1 + if child >= hi { + break + } + if child+1 < hi && (cmp(data[first+child], data[first+child+1]) < 0) { + child++ + } + if !(cmp(data[first+root], data[first+child]) < 0) { + return + } + data[first+root], data[first+child] = data[first+child], data[first+root] + root = child + } +} + +func heapSortCmpFunc[E any](data []E, a, b int, cmp func(a, b E) int) { + first := a + lo := 0 + hi := b - a + + // Build heap with greatest element at top. + for i := (hi - 1) / 2; i >= 0; i-- { + siftDownCmpFunc(data, i, hi, first, cmp) + } + + // Pop elements, largest first, into end of data. + for i := hi - 1; i >= 0; i-- { + data[first], data[first+i] = data[first+i], data[first] + siftDownCmpFunc(data, lo, i, first, cmp) + } +} + +// pdqsortCmpFunc sorts data[a:b]. +// The algorithm based on pattern-defeating quicksort(pdqsort), but without the optimizations from BlockQuicksort. +// pdqsort paper: https://arxiv.org/pdf/2106.05123.pdf +// C++ implementation: https://github.com/orlp/pdqsort +// Rust implementation: https://docs.rs/pdqsort/latest/pdqsort/ +// limit is the number of allowed bad (very unbalanced) pivots before falling back to heapsort. +func pdqsortCmpFunc[E any](data []E, a, b, limit int, cmp func(a, b E) int) { + const maxInsertion = 12 + + var ( + wasBalanced = true // whether the last partitioning was reasonably balanced + wasPartitioned = true // whether the slice was already partitioned + ) + + for { + length := b - a + + if length <= maxInsertion { + insertionSortCmpFunc(data, a, b, cmp) + return + } + + // Fall back to heapsort if too many bad choices were made. + if limit == 0 { + heapSortCmpFunc(data, a, b, cmp) + return + } + + // If the last partitioning was imbalanced, we need to breaking patterns. + if !wasBalanced { + breakPatternsCmpFunc(data, a, b, cmp) + limit-- + } + + pivot, hint := choosePivotCmpFunc(data, a, b, cmp) + if hint == decreasingHint { + reverseRangeCmpFunc(data, a, b, cmp) + // The chosen pivot was pivot-a elements after the start of the array. + // After reversing it is pivot-a elements before the end of the array. + // The idea came from Rust's implementation. + pivot = (b - 1) - (pivot - a) + hint = increasingHint + } + + // The slice is likely already sorted. + if wasBalanced && wasPartitioned && hint == increasingHint { + if partialInsertionSortCmpFunc(data, a, b, cmp) { + return + } + } + + // Probably the slice contains many duplicate elements, partition the slice into + // elements equal to and elements greater than the pivot. + if a > 0 && !(cmp(data[a-1], data[pivot]) < 0) { + mid := partitionEqualCmpFunc(data, a, b, pivot, cmp) + a = mid + continue + } + + mid, alreadyPartitioned := partitionCmpFunc(data, a, b, pivot, cmp) + wasPartitioned = alreadyPartitioned + + leftLen, rightLen := mid-a, b-mid + balanceThreshold := length / 8 + if leftLen < rightLen { + wasBalanced = leftLen >= balanceThreshold + pdqsortCmpFunc(data, a, mid, limit, cmp) + a = mid + 1 + } else { + wasBalanced = rightLen >= balanceThreshold + pdqsortCmpFunc(data, mid+1, b, limit, cmp) + b = mid + } + } +} + +// partitionCmpFunc does one quicksort partition. +// Let p = data[pivot] +// Moves elements in data[a:b] around, so that data[i]
=p for i =p for i