mirror of
https://github.com/golang/go
synced 2024-11-26 05:07:59 -07:00
cmd/compile: fix case where func-valued field of a generic type is called
Added test example orderedmap.go (binary search tree) that requires this fix (calling function compare in _Map). Also added new tests slices.go and metrics.go that just work. Change-Id: Ifa5f42ab6eee9aa54c40f0eca19e00a87f8f608a Reviewed-on: https://go-review.googlesource.com/c/go/+/301829 Trust: Dan Scales <danscales@google.com> Trust: Robert Griesemer <gri@golang.org> Reviewed-by: Robert Griesemer <gri@golang.org>
This commit is contained in:
Dan Scales
parent
c236095638
commit
96aecdcb36
@ -389,6 +389,13 @@ func (subst *subster) node(n ir.Node) ir.Node {
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typecheck.Callee(call.X)
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call.SetTypecheck(0)
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typecheck.Call(call)
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} else if call.X.Op() == ir.ODOT || call.X.Op() == ir.ODOTPTR {
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// An OXDOT for a generic receiver was resolved to
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// an access to a field which has a function
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// value. Typecheck the call to that function, now
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// that the OXDOT was resolved.
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call.SetTypecheck(0)
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typecheck.Call(call)
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} else if call.X.Op() != ir.OFUNCINST {
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// A call with an OFUNCINST will get typechecked
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// in stencil() once we have created & attached the
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196
test/typeparam/metrics.go
Normal file
196
test/typeparam/metrics.go
Normal file
@ -0,0 +1,196 @@
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// run -gcflags=-G=3
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// Copyright 2021 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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// Package metrics provides tracking arbitrary metrics composed of
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// values of comparable types.
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package main
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import (
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"fmt"
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"sort"
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"sync"
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)
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// _Metric1 tracks metrics of values of some type.
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type _Metric1[T comparable] struct {
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mu sync.Mutex
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m map[T]int
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}
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// Add adds another instance of some value.
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func (m *_Metric1[T]) Add(v T) {
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m.mu.Lock()
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defer m.mu.Unlock()
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if m.m == nil {
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m.m = make(map[T]int)
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}
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m.m[v]++
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}
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// Count returns the number of instances we've seen of v.
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func (m *_Metric1[T]) Count(v T) int {
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m.mu.Lock()
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defer m.mu.Unlock()
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return m.m[v]
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}
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// Metrics returns all the values we've seen, in an indeterminate order.
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func (m *_Metric1[T]) Metrics() []T {
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return _Keys(m.m)
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}
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type key2[T1, T2 comparable] struct {
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f1 T1
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f2 T2
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}
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// _Metric2 tracks metrics of pairs of values.
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type _Metric2[T1, T2 comparable] struct {
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mu sync.Mutex
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m map[key2[T1, T2]]int
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}
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// Add adds another instance of some pair of values.
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func (m *_Metric2[T1, T2]) Add(v1 T1, v2 T2) {
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m.mu.Lock()
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defer m.mu.Unlock()
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if m.m == nil {
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m.m = make(map[key2[T1, T2]]int)
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}
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m.m[key2[T1, T2]{v1, v2}]++
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}
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// Count returns the number of instances we've seen of v1/v2.
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func (m *_Metric2[T1, T2]) Count(v1 T1, v2 T2) int {
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m.mu.Lock()
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defer m.mu.Unlock()
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return m.m[key2[T1, T2]{v1, v2}]
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}
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// Metrics returns all the values we've seen, in an indeterminate order.
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func (m *_Metric2[T1, T2]) Metrics() (r1 []T1, r2 []T2) {
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for _, k := range _Keys(m.m) {
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r1 = append(r1, k.f1)
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r2 = append(r2, k.f2)
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}
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return r1, r2
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}
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type key3[T1, T2, T3 comparable] struct {
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f1 T1
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f2 T2
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f3 T3
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}
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// _Metric3 tracks metrics of triplets of values.
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type _Metric3[T1, T2, T3 comparable] struct {
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mu sync.Mutex
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m map[key3[T1, T2, T3]]int
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}
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// Add adds another instance of some triplet of values.
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func (m *_Metric3[T1, T2, T3]) Add(v1 T1, v2 T2, v3 T3) {
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m.mu.Lock()
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defer m.mu.Unlock()
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if m.m == nil {
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m.m = make(map[key3[T1, T2, T3]]int)
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}
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m.m[key3[T1, T2, T3]{v1, v2, v3}]++
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}
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// Count returns the number of instances we've seen of v1/v2/v3.
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func (m *_Metric3[T1, T2, T3]) Count(v1 T1, v2 T2, v3 T3) int {
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m.mu.Lock()
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defer m.mu.Unlock()
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return m.m[key3[T1, T2, T3]{v1, v2, v3}]
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}
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// Metrics returns all the values we've seen, in an indeterminate order.
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func (m *_Metric3[T1, T2, T3]) Metrics() (r1 []T1, r2 []T2, r3 []T3) {
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for k := range m.m {
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r1 = append(r1, k.f1)
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r2 = append(r2, k.f2)
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r3 = append(r3, k.f3)
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}
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return r1, r2, r3
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}
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type S struct{ a, b, c string }
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func TestMetrics() {
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m1 := _Metric1[string]{}
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if got := m1.Count("a"); got != 0 {
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panic(fmt.Sprintf("Count(%q) = %d, want 0", "a", got))
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}
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m1.Add("a")
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m1.Add("a")
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if got := m1.Count("a"); got != 2 {
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panic(fmt.Sprintf("Count(%q) = %d, want 2", "a", got))
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}
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if got, want := m1.Metrics(), []string{"a"}; !_SlicesEqual(got, want) {
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panic(fmt.Sprintf("Metrics = %v, want %v", got, want))
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}
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m2 := _Metric2[int, float64]{}
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m2.Add(1, 1)
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m2.Add(2, 2)
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m2.Add(3, 3)
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m2.Add(3, 3)
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k1, k2 := m2.Metrics()
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sort.Ints(k1)
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w1 := []int{1, 2, 3}
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if !_SlicesEqual(k1, w1) {
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panic(fmt.Sprintf("_Metric2.Metrics first slice = %v, want %v", k1, w1))
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}
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sort.Float64s(k2)
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w2 := []float64{1, 2, 3}
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if !_SlicesEqual(k2, w2) {
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panic(fmt.Sprintf("_Metric2.Metrics first slice = %v, want %v", k2, w2))
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}
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m3 := _Metric3[string, S, S]{}
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m3.Add("a", S{"d", "e", "f"}, S{"g", "h", "i"})
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m3.Add("a", S{"d", "e", "f"}, S{"g", "h", "i"})
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m3.Add("a", S{"d", "e", "f"}, S{"g", "h", "i"})
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m3.Add("b", S{"d", "e", "f"}, S{"g", "h", "i"})
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if got := m3.Count("a", S{"d", "e", "f"}, S{"g", "h", "i"}); got != 3 {
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panic(fmt.Sprintf("Count(%v, %v, %v) = %d, want 3", "a", S{"d", "e", "f"}, S{"g", "h", "i"}, got))
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}
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}
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func main() {
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TestMetrics()
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}
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// _Equal reports whether two slices are equal: the same length and all
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// elements equal. All floating point NaNs are considered equal.
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func _SlicesEqual[Elem comparable](s1, s2 []Elem) bool {
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if len(s1) != len(s2) {
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return false
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}
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for i, v1 := range s1 {
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v2 := s2[i]
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if v1 != v2 {
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isNaN := func(f Elem) bool { return f != f }
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if !isNaN(v1) || !isNaN(v2) {
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return false
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}
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}
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}
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return true
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}
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// _Keys returns the keys of the map m.
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// The keys will be an indeterminate order.
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func _Keys[K comparable, V any](m map[K]V) []K {
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r := make([]K, 0, len(m))
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for k := range m {
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r = append(r, k)
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}
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return r
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}
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286
test/typeparam/orderedmap.go
Normal file
286
test/typeparam/orderedmap.go
Normal file
@ -0,0 +1,286 @@
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// run -gcflags=-G=3
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// Copyright 2021 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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// Package orderedmap provides an ordered map, implemented as a binary tree.
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package main
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import (
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"bytes"
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"context"
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"fmt"
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"runtime"
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)
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type Ordered interface {
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type int, int8, int16, int32, int64,
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uint, uint8, uint16, uint32, uint64, uintptr,
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float32, float64,
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string
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}
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// _Map is an ordered map.
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type _Map[K, V any] struct {
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root *node[K, V]
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compare func(K, K) int
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}
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// node is the type of a node in the binary tree.
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type node[K, V any] struct {
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key K
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val V
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left, right *node[K, V]
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}
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// _New returns a new map. It takes a comparison function that compares two
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// keys and returns < 0 if the first is less, == 0 if they are equal,
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// > 0 if the first is greater.
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func _New[K, V any](compare func(K, K) int) *_Map[K, V] {
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return &_Map[K, V]{compare: compare}
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}
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// _NewOrdered returns a new map whose key is an ordered type.
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// This is like _New, but does not require providing a compare function.
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// The map compare function uses the obvious key ordering.
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func _NewOrdered[K Ordered, V any]() *_Map[K, V] {
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return _New[K, V](func(k1, k2 K) int {
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switch {
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case k1 < k2:
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return -1
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case k1 == k2:
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return 0
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default:
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return 1
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}
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})
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}
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// find looks up key in the map, returning either a pointer to the slot of the
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// node holding key, or a pointer to the slot where should a node would go.
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func (m *_Map[K, V]) find(key K) **node[K, V] {
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pn := &m.root
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for *pn != nil {
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switch cmp := m.compare(key, (*pn).key); {
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case cmp < 0:
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pn = &(*pn).left
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case cmp > 0:
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pn = &(*pn).right
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default:
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return pn
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}
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}
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return pn
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}
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// Insert inserts a new key/value into the map.
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// If the key is already present, the value is replaced.
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// Reports whether this is a new key.
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func (m *_Map[K, V]) Insert(key K, val V) bool {
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pn := m.find(key)
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if *pn != nil {
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(*pn).val = val
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return false
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}
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*pn = &node[K, V]{key: key, val: val}
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return true
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}
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// Find returns the value associated with a key, or the zero value
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// if not present. The found result reports whether the key was found.
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func (m *_Map[K, V]) Find(key K) (V, bool) {
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pn := m.find(key)
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if *pn == nil {
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var zero V
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return zero, false
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}
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return (*pn).val, true
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}
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// keyValue is a pair of key and value used while iterating.
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type keyValue[K, V any] struct {
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key K
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val V
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}
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// iterate returns an iterator that traverses the map.
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func (m *_Map[K, V]) Iterate() *_Iterator[K, V] {
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sender, receiver := _Ranger[keyValue[K, V]]()
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var f func(*node[K, V]) bool
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f = func(n *node[K, V]) bool {
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if n == nil {
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return true
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}
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// Stop the traversal if Send fails, which means that
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// nothing is listening to the receiver.
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return f(n.left) &&
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sender.Send(context.Background(), keyValue[K, V]{n.key, n.val}) &&
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f(n.right)
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}
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go func() {
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f(m.root)
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sender.Close()
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}()
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return &_Iterator[K, V]{receiver}
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}
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// _Iterator is used to iterate over the map.
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type _Iterator[K, V any] struct {
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r *_Receiver[keyValue[K, V]]
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}
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// Next returns the next key and value pair, and a boolean that reports
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// whether they are valid. If not valid, we have reached the end of the map.
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func (it *_Iterator[K, V]) Next() (K, V, bool) {
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keyval, ok := it.r.Next(context.Background())
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if !ok {
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var zerok K
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var zerov V
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return zerok, zerov, false
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}
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return keyval.key, keyval.val, true
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}
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func TestMap() {
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m := _New[[]byte, int](bytes.Compare)
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if _, found := m.Find([]byte("a")); found {
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panic(fmt.Sprintf("unexpectedly found %q in empty map", []byte("a")))
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}
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if !m.Insert([]byte("a"), 'a') {
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panic(fmt.Sprintf("key %q unexpectedly already present", []byte("a")))
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}
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if !m.Insert([]byte("c"), 'c') {
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panic(fmt.Sprintf("key %q unexpectedly already present", []byte("c")))
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}
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if !m.Insert([]byte("b"), 'b') {
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panic(fmt.Sprintf("key %q unexpectedly already present", []byte("b")))
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}
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if m.Insert([]byte("c"), 'x') {
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panic(fmt.Sprintf("key %q unexpectedly not present", []byte("c")))
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}
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if v, found := m.Find([]byte("a")); !found {
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panic(fmt.Sprintf("did not find %q", []byte("a")))
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} else if v != 'a' {
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panic(fmt.Sprintf("key %q returned wrong value %c, expected %c", []byte("a"), v, 'a'))
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}
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if v, found := m.Find([]byte("c")); !found {
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panic(fmt.Sprintf("did not find %q", []byte("c")))
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} else if v != 'x' {
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panic(fmt.Sprintf("key %q returned wrong value %c, expected %c", []byte("c"), v, 'x'))
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}
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if _, found := m.Find([]byte("d")); found {
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panic(fmt.Sprintf("unexpectedly found %q", []byte("d")))
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}
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gather := func(it *_Iterator[[]byte, int]) []int {
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var r []int
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for {
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_, v, ok := it.Next()
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if !ok {
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return r
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}
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r = append(r, v)
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}
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}
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got := gather(m.Iterate())
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want := []int{'a', 'b', 'x'}
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if !_SliceEqual(got, want) {
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panic(fmt.Sprintf("Iterate returned %v, want %v", got, want))
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}
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}
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func main() {
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TestMap()
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}
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|
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// _Equal reports whether two slices are equal: the same length and all
|
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// elements equal. All floating point NaNs are considered equal.
|
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func _SliceEqual[Elem comparable](s1, s2 []Elem) bool {
|
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if len(s1) != len(s2) {
|
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return false
|
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}
|
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for i, v1 := range s1 {
|
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v2 := s2[i]
|
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if v1 != v2 {
|
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isNaN := func(f Elem) bool { return f != f }
|
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if !isNaN(v1) || !isNaN(v2) {
|
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return false
|
||||
}
|
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}
|
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}
|
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return true
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}
|
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|
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// Ranger returns a Sender and a Receiver. The Receiver provides a
|
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// Next method to retrieve values. The Sender provides a Send method
|
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// to send values and a Close method to stop sending values. The Next
|
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// method indicates when the Sender has been closed, and the Send
|
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// method indicates when the Receiver has been freed.
|
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//
|
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// This is a convenient way to exit a goroutine sending values when
|
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// the receiver stops reading them.
|
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func _Ranger[Elem any]() (*_Sender[Elem], *_Receiver[Elem]) {
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c := make(chan Elem)
|
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d := make(chan struct{})
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s := &_Sender[Elem]{
|
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values: c,
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done: d,
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}
|
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r := &_Receiver[Elem] {
|
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values: c,
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done: d,
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}
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runtime.SetFinalizer(r, (*_Receiver[Elem]).finalize)
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return s, r
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}
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|
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// A _Sender is used to send values to a Receiver.
|
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type _Sender[Elem any] struct {
|
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values chan<- Elem
|
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done <-chan struct{}
|
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}
|
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|
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// Send sends a value to the receiver. It reports whether the value was sent.
|
||||
// The value will not be sent if the context is closed or the receiver
|
||||
// is freed.
|
||||
func (s *_Sender[Elem]) Send(ctx context.Context, v Elem) bool {
|
||||
select {
|
||||
case <-ctx.Done():
|
||||
return false
|
||||
case s.values <- v:
|
||||
return true
|
||||
case <-s.done:
|
||||
return false
|
||||
}
|
||||
}
|
||||
|
||||
// Close tells the receiver that no more values will arrive.
|
||||
// After Close is called, the _Sender may no longer be used.
|
||||
func (s *_Sender[Elem]) Close() {
|
||||
close(s.values)
|
||||
}
|
||||
|
||||
// A _Receiver receives values from a _Sender.
|
||||
type _Receiver[Elem any] struct {
|
||||
values <-chan Elem
|
||||
done chan<- struct{}
|
||||
}
|
||||
|
||||
// Next returns the next value from the channel. The bool result indicates
|
||||
// whether the value is valid.
|
||||
func (r *_Receiver[Elem]) Next(ctx context.Context) (v Elem, ok bool) {
|
||||
select {
|
||||
case <-ctx.Done():
|
||||
case v, ok = <-r.values:
|
||||
}
|
||||
return v, ok
|
||||
}
|
||||
|
||||
// finalize is a finalizer for the receiver.
|
||||
func (r *_Receiver[Elem]) finalize() {
|
||||
close(r.done)
|
||||
}
|
||||
318
test/typeparam/slices.go
Normal file
318
test/typeparam/slices.go
Normal file
@ -0,0 +1,318 @@
|
||||
// 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 slices provides functions for basic operations on
|
||||
// slices of any element type.
|
||||
package main
|
||||
|
||||
import (
|
||||
"fmt"
|
||||
"math"
|
||||
"strings"
|
||||
)
|
||||
|
||||
type Ordered interface {
|
||||
type int, int8, int16, int32, int64,
|
||||
uint, uint8, uint16, uint32, uint64, uintptr,
|
||||
float32, float64,
|
||||
string
|
||||
}
|
||||
|
||||
type Integer interface {
|
||||
type int, int8, int16, int32, int64,
|
||||
uint, uint8, uint16, uint32, uint64, uintptr
|
||||
}
|
||||
|
||||
// Max returns the maximum of two values of some ordered type.
|
||||
func _Max[T Ordered](a, b T) T {
|
||||
if a > b {
|
||||
return a
|
||||
}
|
||||
return b
|
||||
}
|
||||
|
||||
// Min returns the minimum of two values of some ordered type.
|
||||
func _Min[T Ordered](a, b T) T {
|
||||
if a < b {
|
||||
return a
|
||||
}
|
||||
return b
|
||||
}
|
||||
|
||||
// _Equal reports whether two slices are equal: the same length and all
|
||||
// elements equal. All floating point NaNs are considered equal.
|
||||
func _Equal[Elem comparable](s1, s2 []Elem) bool {
|
||||
if len(s1) != len(s2) {
|
||||
return false
|
||||
}
|
||||
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
|
||||
}
|
||||
|
||||
// _EqualFn reports whether two slices are equal using a comparision
|
||||
// function on each element.
|
||||
func _EqualFn[Elem any](s1, s2 []Elem, eq func(Elem, Elem) 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
|
||||
}
|
||||
|
||||
// _Map turns a []Elem1 to a []Elem2 using a mapping function.
|
||||
func _Map[Elem1, Elem2 any](s []Elem1, f func(Elem1) Elem2) []Elem2 {
|
||||
r := make([]Elem2, len(s))
|
||||
for i, v := range s {
|
||||
r[i] = f(v)
|
||||
}
|
||||
return r
|
||||
}
|
||||
|
||||
// _Reduce reduces a []Elem1 to a single value of type Elem2 using
|
||||
// a reduction function.
|
||||
func _Reduce[Elem1, Elem2 any](s []Elem1, initializer Elem2, f func(Elem2, Elem1) Elem2) Elem2 {
|
||||
r := initializer
|
||||
for _, v := range s {
|
||||
r = f(r, v)
|
||||
}
|
||||
return r
|
||||
}
|
||||
|
||||
// _Filter filters values from a slice using a filter function.
|
||||
func _Filter[Elem any](s []Elem, f func(Elem) bool) []Elem {
|
||||
var r []Elem
|
||||
for _, v := range s {
|
||||
if f(v) {
|
||||
r = append(r, v)
|
||||
}
|
||||
}
|
||||
return r
|
||||
}
|
||||
|
||||
// _Max returns the maximum element in a slice of some ordered type.
|
||||
// If the slice is empty it returns the zero value of the element type.
|
||||
func _SliceMax[Elem Ordered](s []Elem) Elem {
|
||||
if len(s) == 0 {
|
||||
var zero Elem
|
||||
return zero
|
||||
}
|
||||
return _Reduce(s[1:], s[0], _Max[Elem])
|
||||
}
|
||||
|
||||
// _Min returns the minimum element in a slice of some ordered type.
|
||||
// If the slice is empty it returns the zero value of the element type.
|
||||
func _SliceMin[Elem Ordered](s []Elem) Elem {
|
||||
if len(s) == 0 {
|
||||
var zero Elem
|
||||
return zero
|
||||
}
|
||||
return _Reduce(s[1:], s[0], _Min[Elem])
|
||||
}
|
||||
|
||||
// _Append adds values to the end of a slice, returning a new slice.
|
||||
// This is like the predeclared append function; it's an example
|
||||
// of how to write it using generics. We used to write code like
|
||||
// this before append was added to the language, but we had to write
|
||||
// a separate copy for each type.
|
||||
func _Append[T any](s []T, t ...T) []T {
|
||||
lens := len(s)
|
||||
tot := lens + len(t)
|
||||
if tot <= cap(s) {
|
||||
s = s[:tot]
|
||||
} else {
|
||||
news := make([]T, tot, tot + tot/2)
|
||||
_Copy(news, s)
|
||||
s = news
|
||||
}
|
||||
_Copy(s[lens:tot], t)
|
||||
return s
|
||||
}
|
||||
|
||||
// _Copy copies values from t to s, stopping when either slice is full,
|
||||
// returning the number of values copied. This is like the predeclared
|
||||
// copy function; it's an example of how to write it using generics.
|
||||
func _Copy[T any](s, t []T) int {
|
||||
i := 0
|
||||
for ; i < len(s) && i < len(t); i++ {
|
||||
s[i] = t[i]
|
||||
}
|
||||
return i
|
||||
}
|
||||
|
||||
func TestEqual() {
|
||||
s1 := []int{1, 2, 3}
|
||||
if !_Equal(s1, s1) {
|
||||
panic(fmt.Sprintf("_Equal(%v, %v) = false, want true", s1, s1))
|
||||
}
|
||||
s2 := []int{1, 2, 3}
|
||||
if !_Equal(s1, s2) {
|
||||
panic(fmt.Sprintf("_Equal(%v, %v) = false, want true", s1, s2))
|
||||
}
|
||||
s2 = append(s2, 4)
|
||||
if _Equal(s1, s2) {
|
||||
panic(fmt.Sprintf("_Equal(%v, %v) = true, want false", s1, s2))
|
||||
}
|
||||
|
||||
s3 := []float64{1, 2, math.NaN()}
|
||||
if !_Equal(s3, s3) {
|
||||
panic(fmt.Sprintf("_Equal(%v, %v) = false, want true", s3, s3))
|
||||
}
|
||||
|
||||
if _Equal(s1, nil) {
|
||||
panic(fmt.Sprintf("_Equal(%v, nil) = true, want false", s1))
|
||||
}
|
||||
if _Equal(nil, s1) {
|
||||
panic(fmt.Sprintf("_Equal(nil, %v) = true, want false", s1))
|
||||
}
|
||||
if !_Equal(s1[:0], nil) {
|
||||
panic(fmt.Sprintf("_Equal(%v, nil = false, want true", s1[:0]))
|
||||
}
|
||||
}
|
||||
|
||||
func offByOne[Elem Integer](a, b Elem) bool {
|
||||
return a == b + 1 || a == b - 1
|
||||
}
|
||||
|
||||
func TestEqualFn() {
|
||||
s1 := []int{1, 2, 3}
|
||||
s2 := []int{2, 3, 4}
|
||||
if _EqualFn(s1, s1, offByOne[int]) {
|
||||
panic(fmt.Sprintf("_EqualFn(%v, %v, offByOne) = true, want false", s1, s1))
|
||||
}
|
||||
if !_EqualFn(s1, s2, offByOne[int]) {
|
||||
panic(fmt.Sprintf("_EqualFn(%v, %v, offByOne) = false, want true", s1, s2))
|
||||
}
|
||||
|
||||
if !_EqualFn(s1[:0], nil, offByOne[int]) {
|
||||
panic(fmt.Sprintf("_EqualFn(%v, nil, offByOne) = false, want true", s1[:0]))
|
||||
}
|
||||
|
||||
s3 := []string{"a", "b", "c"}
|
||||
s4 := []string{"A", "B", "C"}
|
||||
if !_EqualFn(s3, s4, strings.EqualFold) {
|
||||
panic(fmt.Sprintf("_EqualFn(%v, %v, strings.EqualFold) = false, want true", s3, s4))
|
||||
}
|
||||
}
|
||||
|
||||
func TestMap() {
|
||||
s1 := []int{1, 2, 3}
|
||||
s2 := _Map(s1, func(i int) float64 { return float64(i) * 2.5 })
|
||||
if want := []float64{2.5, 5, 7.5}; !_Equal(s2, want) {
|
||||
panic(fmt.Sprintf("_Map(%v, ...) = %v, want %v", s1, s2, want))
|
||||
}
|
||||
|
||||
s3 := []string{"Hello", "World"}
|
||||
s4 := _Map(s3, strings.ToLower)
|
||||
if want := []string{"hello", "world"}; !_Equal(s4, want) {
|
||||
panic(fmt.Sprintf("_Map(%v, strings.ToLower) = %v, want %v", s3, s4, want))
|
||||
}
|
||||
|
||||
s5 := _Map(nil, func(i int) int { return i })
|
||||
if len(s5) != 0 {
|
||||
panic(fmt.Sprintf("_Map(nil, identity) = %v, want empty slice", s5))
|
||||
}
|
||||
}
|
||||
|
||||
func TestReduce() {
|
||||
s1 := []int{1, 2, 3}
|
||||
r := _Reduce(s1, 0, func(f float64, i int) float64 { return float64(i) * 2.5 + f })
|
||||
if want := 15.0; r != want {
|
||||
panic(fmt.Sprintf("_Reduce(%v, 0, ...) = %v, want %v", s1, r, want))
|
||||
}
|
||||
|
||||
if got := _Reduce(nil, 0, func(i, j int) int { return i + j}); got != 0 {
|
||||
panic(fmt.Sprintf("_Reduce(nil, 0, add) = %v, want 0", got))
|
||||
}
|
||||
}
|
||||
|
||||
func TestFilter() {
|
||||
s1 := []int{1, 2, 3}
|
||||
s2 := _Filter(s1, func(i int) bool { return i%2 == 0 })
|
||||
if want := []int{2}; !_Equal(s2, want) {
|
||||
panic(fmt.Sprintf("_Filter(%v, even) = %v, want %v", s1, s2, want))
|
||||
}
|
||||
|
||||
if s3 := _Filter(s1[:0], func(i int) bool { return true }); len(s3) > 0 {
|
||||
panic(fmt.Sprintf("_Filter(%v, identity) = %v, want empty slice", s1[:0], s3))
|
||||
}
|
||||
}
|
||||
|
||||
func TestMax() {
|
||||
s1 := []int{1, 2, 3, -5}
|
||||
if got, want := _SliceMax(s1), 3; got != want {
|
||||
panic(fmt.Sprintf("_Max(%v) = %d, want %d", s1, got, want))
|
||||
}
|
||||
|
||||
s2 := []string{"aaa", "a", "aa", "aaaa"}
|
||||
if got, want := _SliceMax(s2), "aaaa"; got != want {
|
||||
panic(fmt.Sprintf("_Max(%v) = %q, want %q", s2, got, want))
|
||||
}
|
||||
|
||||
if got, want := _SliceMax(s2[:0]), ""; got != want {
|
||||
panic(fmt.Sprintf("_Max(%v) = %q, want %q", s2[:0], got, want))
|
||||
}
|
||||
}
|
||||
|
||||
func TestMin() {
|
||||
s1 := []int{1, 2, 3, -5}
|
||||
if got, want := _SliceMin(s1), -5; got != want {
|
||||
panic(fmt.Sprintf("_Min(%v) = %d, want %d", s1, got, want))
|
||||
}
|
||||
|
||||
s2 := []string{"aaa", "a", "aa", "aaaa"}
|
||||
if got, want := _SliceMin(s2), "a"; got != want {
|
||||
panic(fmt.Sprintf("_Min(%v) = %q, want %q", s2, got, want))
|
||||
}
|
||||
|
||||
if got, want := _SliceMin(s2[:0]), ""; got != want {
|
||||
panic(fmt.Sprintf("_Min(%v) = %q, want %q", s2[:0], got, want))
|
||||
}
|
||||
}
|
||||
|
||||
func TestAppend() {
|
||||
s := []int{1, 2, 3}
|
||||
s = _Append(s, 4, 5, 6)
|
||||
want := []int{1, 2, 3, 4, 5, 6}
|
||||
if !_Equal(s, want) {
|
||||
panic(fmt.Sprintf("after _Append got %v, want %v", s, want))
|
||||
}
|
||||
}
|
||||
|
||||
func TestCopy() {
|
||||
s1 := []int{1, 2, 3}
|
||||
s2 := []int{4, 5}
|
||||
if got := _Copy(s1, s2); got != 2 {
|
||||
panic(fmt.Sprintf("_Copy returned %d, want 2", got))
|
||||
}
|
||||
want := []int{4, 5, 3}
|
||||
if !_Equal(s1, want) {
|
||||
panic(fmt.Sprintf("after _Copy got %v, want %v", s1, want))
|
||||
}
|
||||
}
|
||||
func main() {
|
||||
TestEqual()
|
||||
TestEqualFn()
|
||||
TestMap()
|
||||
TestReduce()
|
||||
TestFilter()
|
||||
TestMax()
|
||||
TestMin()
|
||||
TestAppend()
|
||||
TestCopy()
|
||||
}
|
||||
Loading…
Reference in New Issue
Block a user