Merge pull request #34 from laher/sets

Set + SortedSet with tests

Author: benbjohnson

sets.go

@@ -0,0 +1,170 @@
+package immutable
+
+type Set[T comparable] struct {
+	m *Map[T, struct{}]
+}
+
+func NewSet[T comparable](hasher Hasher[T]) Set[T] {
+	return Set[T]{
+		m: NewMap[T, struct{}](hasher),
+	}
+}
+
+func (s Set[T]) Set(val T) Set[T] {
+	return Set[T]{
+		m: s.m.Set(val, struct{}{}),
+	}
+}
+
+func (s Set[T]) Delete(val T) Set[T] {
+	return Set[T]{
+		m: s.m.Delete(val),
+	}
+}
+
+func (s Set[T]) Has(val T) bool {
+	_, ok := s.m.Get(val)
+	return ok
+}
+
+func (s Set[K]) Len() int {
+	return s.m.Len()
+}
+
+func (s Set[T]) Iterator() *SetIterator[T] {
+	itr := &SetIterator[T]{mi: s.m.Iterator()}
+	itr.mi.First()
+	return itr
+}
+
+type SetIterator[T comparable] struct {
+	mi *MapIterator[T, struct{}]
+}
+
+func (itr *SetIterator[T]) Done() bool {
+	return itr.mi.Done()
+}
+
+func (itr *SetIterator[T]) First() {
+	itr.mi.First()
+}
+
+func (itr *SetIterator[T]) Next() (val T, ok bool) {
+	val, _, ok = itr.mi.Next()
+	return
+}
+
+type SetBuilder[T comparable] struct {
+	s Set[T]
+}
+
+func NewSetBuilder[T comparable](hasher Hasher[T]) *SetBuilder[T] {
+	return &SetBuilder[T]{s: NewSet(hasher)}
+}
+
+func (s SetBuilder[T]) Set(val T) {
+	s.s.m = s.s.m.set(val, struct{}{}, true)
+}
+
+func (s SetBuilder[T]) Delete(val T) {
+	s.s.m = s.s.m.delete(val, true)
+}
+
+func (s SetBuilder[T]) Has(val T) bool {
+	return s.s.Has(val)
+}
+
+func (s SetBuilder[T]) Len() int {
+	return s.s.Len()
+}
+
+type SortedSet[T comparable] struct {
+	m *SortedMap[T, struct{}]
+}
+
+func NewSortedSet[T comparable](comparer Comparer[T]) SortedSet[T] {
+	return SortedSet[T]{
+		m: NewSortedMap[T, struct{}](comparer),
+	}
+}
+
+func (s SortedSet[T]) Put(val T) SortedSet[T] {
+	return SortedSet[T]{
+		m: s.m.Set(val, struct{}{}),
+	}
+}
+
+func (s SortedSet[T]) Delete(val T) SortedSet[T] {
+	return SortedSet[T]{
+		m: s.m.Delete(val),
+	}
+}
+
+func (s SortedSet[T]) Has(val T) bool {
+	_, ok := s.m.Get(val)
+	return ok
+}
+
+func (s SortedSet[K]) Len() int {
+	return s.m.Len()
+}
+
+func (s SortedSet[T]) Iterator() *SortedSetIterator[T] {
+	itr := &SortedSetIterator[T]{mi: s.m.Iterator()}
+	itr.mi.First()
+	return itr
+}
+
+type SortedSetIterator[T comparable] struct {
+	mi *SortedMapIterator[T, struct{}]
+}
+
+func (itr *SortedSetIterator[T]) Done() bool {
+	return itr.mi.Done()
+}
+
+func (itr *SortedSetIterator[T]) First() {
+	itr.mi.First()
+}
+
+func (itr *SortedSetIterator[T]) Last() {
+	itr.mi.Last()
+}
+
+func (itr *SortedSetIterator[T]) Next() (val T, ok bool) {
+	val, _, ok = itr.mi.Next()
+	return
+}
+
+func (itr *SortedSetIterator[T]) Prev() (val T, ok bool) {
+	val, _, ok = itr.mi.Prev()
+	return
+}
+
+func (itr *SortedSetIterator[T]) Seek(val T) {
+	itr.mi.Seek(val)
+}
+
+type SortedSetBuilder[T comparable] struct {
+	s SortedSet[T]
+}
+
+func NewSortedSetBuilder[T comparable](comparer Comparer[T]) *SortedSetBuilder[T] {
+	return &SortedSetBuilder[T]{s: NewSortedSet(comparer)}
+}
+
+func (s SortedSetBuilder[T]) Set(val T) {
+	s.s.m = s.s.m.set(val, struct{}{}, true)
+}
+
+func (s SortedSetBuilder[T]) Delete(val T) {
+	s.s.m = s.s.m.delete(val, true)
+}
+
+func (s SortedSetBuilder[T]) Has(val T) bool {
+	return s.s.Has(val)
+}
+
+func (s SortedSetBuilder[T]) Len() int {
+	return s.s.Len()
+}

sets_test.go

@@ -0,0 +1,102 @@
+package immutable
+
+import (
+	"testing"
+)
+
+func TestSetsPut(t *testing.T) {
+	s := NewSet[string](nil)
+	s2 := s.Set("1").Set("1")
+	if s.Len() != 0 {
+		t.Fatalf("Unexpected mutation of set")
+	}
+	if s.Has("1") {
+		t.Fatalf("Unexpected set element")
+	}
+	if s2.Len() != 1 {
+		t.Fatalf("Unexpected non-mutation of set")
+	}
+	if !s2.Has("1") {
+		t.Fatalf("Set element missing")
+	}
+	itr := s2.Iterator()
+	counter := 0
+	for !itr.Done() {
+		i, v := itr.Next()
+		t.Log(i, v)
+		counter++
+	}
+	if counter != 1 {
+		t.Fatalf("iterator wrong length")
+	}
+}
+
+func TestSetsDelete(t *testing.T) {
+	s := NewSet[string](nil)
+	s2 := s.Set("1")
+	s3 := s.Delete("1")
+	if s2.Len() != 1 {
+		t.Fatalf("Unexpected non-mutation of set")
+	}
+	if !s2.Has("1") {
+		t.Fatalf("Set element missing")
+	}
+	if s3.Len() != 0 {
+		t.Fatalf("Unexpected set length after delete")
+	}
+	if s3.Has("1") {
+		t.Fatalf("Unexpected set element after delete")
+	}
+}
+
+func TestSortedSetsPut(t *testing.T) {
+	s := NewSortedSet[string](nil)
+	s2 := s.Put("1").Put("1").Put("0")
+	if s.Len() != 0 {
+		t.Fatalf("Unexpected mutation of set")
+	}
+	if s.Has("1") {
+		t.Fatalf("Unexpected set element")
+	}
+	if s2.Len() != 2 {
+		t.Fatalf("Unexpected non-mutation of set")
+	}
+	if !s2.Has("1") {
+		t.Fatalf("Set element missing")
+	}
+
+	itr := s2.Iterator()
+	counter := 0
+	for !itr.Done() {
+		i, v := itr.Next()
+		t.Log(i, v)
+		if counter == 0 && i != "0" {
+			t.Fatalf("sort did not work for first el")
+		}
+		if counter == 1 && i != "1" {
+			t.Fatalf("sort did not work for second el")
+		}
+		counter++
+	}
+	if counter != 2 {
+		t.Fatalf("iterator wrong length")
+	}
+}
+
+func TestSortedSetsDelete(t *testing.T) {
+	s := NewSortedSet[string](nil)
+	s2 := s.Put("1")
+	s3 := s.Delete("1")
+	if s2.Len() != 1 {
+		t.Fatalf("Unexpected non-mutation of set")
+	}
+	if !s2.Has("1") {
+		t.Fatalf("Set element missing")
+	}
+	if s3.Len() != 0 {
+		t.Fatalf("Unexpected set length after delete")
+	}
+	if s3.Has("1") {
+		t.Fatalf("Unexpected set element after delete")
+	}
+}