blob: 0f539d659c39785752cd29083cfad45161bd29ec [file] [log] [blame]
// run -gcflags=-G=3
// 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 main
import (
"fmt"
"math"
"sort"
)
type Ordered interface {
~int | ~int8 | ~int16 | ~int32 | ~int64 |
~uint | ~uint8 | ~uint16 | ~uint32 | ~uint64 | ~uintptr |
~float32 | ~float64 |
~string
}
type orderedSlice[Elem Ordered] []Elem
func (s orderedSlice[Elem]) Len() int { return len(s) }
func (s orderedSlice[Elem]) Less(i, j int) bool {
if s[i] < s[j] {
return true
}
isNaN := func(f Elem) bool { return f != f }
if isNaN(s[i]) && !isNaN(s[j]) {
return true
}
return false
}
func (s orderedSlice[Elem]) Swap(i, j int) { s[i], s[j] = s[j], s[i] }
func _OrderedSlice[Elem Ordered](s []Elem) {
sort.Sort(orderedSlice[Elem](s))
}
var ints = []int{74, 59, 238, -784, 9845, 959, 905, 0, 0, 42, 7586, -5467984, 7586}
var float64s = []float64{74.3, 59.0, math.Inf(1), 238.2, -784.0, 2.3, math.NaN(), math.NaN(), math.Inf(-1), 9845.768, -959.7485, 905, 7.8, 7.8}
var strings = []string{"", "Hello", "foo", "bar", "foo", "f00", "%*&^*&^&", "***"}
func TestSortOrderedInts() bool {
return testOrdered("ints", ints, sort.Ints)
}
func TestSortOrderedFloat64s() bool {
return testOrdered("float64s", float64s, sort.Float64s)
}
func TestSortOrderedStrings() bool {
return testOrdered("strings", strings, sort.Strings)
}
func testOrdered[Elem Ordered](name string, s []Elem, sorter func([]Elem)) bool {
s1 := make([]Elem, len(s))
copy(s1, s)
s2 := make([]Elem, len(s))
copy(s2, s)
_OrderedSlice(s1)
sorter(s2)
ok := true
if !sliceEq(s1, s2) {
fmt.Printf("%s: got %v, want %v", name, s1, s2)
ok = false
}
for i := len(s1) - 1; i > 0; i-- {
if s1[i] < s1[i-1] {
fmt.Printf("%s: element %d (%v) < element %d (%v)", name, i, s1[i], i-1, s1[i-1])
ok = false
}
}
return ok
}
func sliceEq[Elem Ordered](s1, s2 []Elem) bool {
for i, v1 := range s1 {
v2 := s2[i]
if v1 != v2 {
isNaN := func(f Elem) bool { return f != f }
if !isNaN(v1) || !isNaN(v2) {
return false
}
}
}
return true
}
func main() {
if !TestSortOrderedInts() || !TestSortOrderedFloat64s() || !TestSortOrderedStrings() {
panic("failure")
}
}