feat: implementing reverse operation (#11)

benchmark/reverse_test.go

@@ -0,0 +1,50 @@
+package benchmark
+
+import (
+	"github.com/wesovilabs/koazee"
+	"testing"
+)
+
+func BenchmarkReverseString10SumLen(b *testing.B) {
+	b.StopTimer()
+	input := strings10
+	for i := 0; i < b.N; i++ {
+		stream := koazee.
+			StreamOf(input)
+		b.StartTimer()
+		stream.Reverse().Do()
+	}
+}
+
+func BenchmarkReverseString100SumLen(b *testing.B) {
+	b.StopTimer()
+	input := strings100
+	for i := 0; i < b.N; i++ {
+		stream := koazee.
+			StreamOf(input)
+		b.StartTimer()
+		stream.Reverse().Do()
+	}
+}
+
+func BenchmarkReverseString1000SumLen(b *testing.B) {
+	b.StopTimer()
+	input := strings1000
+	for i := 0; i < b.N; i++ {
+		stream := koazee.
+			StreamOf(input)
+		b.StartTimer()
+		stream.Reverse().Do()
+	}
+}
+
+func BenchmarkReverseString5000SumLen(b *testing.B) {
+	b.StopTimer()
+	input := strings5000
+	for i := 0; i < b.N; i++ {
+		stream := koazee.
+			StreamOf(input)
+		b.StartTimer()
+		stream.Reverse().Do()
+	}
+}

go.mod

@@ -4,6 +4,7 @@ require (
 	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/divan/depscheck v0.0.0-20160406124124-bf02ca53aeea // indirect
 	github.com/golangci/golangci-lint v1.12.3 // indirect
+	github.com/magiconair/properties v1.7.6
 	github.com/mattn/go-runewidth v0.0.3 // indirect
 	github.com/olekukonko/tablewriter v0.0.1 // indirect
 	github.com/stretchr/testify v1.2.2

internal/reverse/dispatcher.go

@@ -0,0 +1,313 @@
+
+package reverse
+
+import (
+	"reflect"
+)
+
+
+type dispatchFunction func(items reflect.Value)interface{} 
+
+var dispatcher = map[string]dispatchFunction{
+	"string":  reverseString,
+	"*string":  reverseStringPtr,
+	"bool":  reverseBool,
+	"*bool":  reverseBoolPtr,
+	"int":  reverseInt,
+	"*int":  reverseIntPtr,
+	"int8":  reverseInt8,
+	"*int8":  reverseInt8Ptr,
+	"int16":  reverseInt16,
+	"*int16":  reverseInt16Ptr,
+	"int32":  reverseInt32,
+	"*int32":  reverseInt32Ptr,
+	"int64":  reverseInt64,
+	"*int64":  reverseInt64Ptr,
+	"uint":  reverseUint,
+	"*uint":  reverseUintPtr,
+	"uint8":  reverseUint8,
+	"*uint8":  reverseUint8Ptr,
+	"uint16":  reverseUint16,
+	"*uint16":  reverseUint16Ptr,
+	"uint32":  reverseUint32,
+	"*uint32":  reverseUint32Ptr,
+	"uint64":  reverseUint64,
+	"*uint64":  reverseUint64Ptr,
+	"float32":  reverseFloat32,
+	"*float32":  reverseFloat32Ptr,
+	"float64":  reverseFloat64,
+	"*float64":  reverseFloat64Ptr,
+}
+
+func dispatch(items reflect.Value, itemsType reflect.Type) (bool,interface{}) {
+	if fnVal, ok := dispatcher[itemsType.String()]; ok {
+		return true,fnVal(items)
+	}
+	return false,nil
+}
+func reverseString(itemsValue reflect.Value) interface{}{
+	input := itemsValue.Interface().([]string)
+	len := len(input)
+	output := make([]string, len)
+	for index := 0; index < (len/2)+1; index++ {
+		output[index], output[len-1-index] = input[len-1-index], input[index]
+	}
+	return output
+}
+
+func reverseStringPtr(itemsValue reflect.Value) interface{}{
+	input := itemsValue.Interface().([]*string)
+	len := len(input)
+	output := make([]*string, len)
+	for index := 0; index < (len/2)+1; index++ {
+		output[index], output[len-1-index] = input[len-1-index], input[index]
+	}
+	return output
+}
+func reverseBool(itemsValue reflect.Value) interface{}{
+	input := itemsValue.Interface().([]bool)
+	len := len(input)
+	output := make([]bool, len)
+	for index := 0; index < (len/2)+1; index++ {
+		output[index], output[len-1-index] = input[len-1-index], input[index]
+	}
+	return output
+}
+
+func reverseBoolPtr(itemsValue reflect.Value) interface{}{
+	input := itemsValue.Interface().([]*bool)
+	len := len(input)
+	output := make([]*bool, len)
+	for index := 0; index < (len/2)+1; index++ {
+		output[index], output[len-1-index] = input[len-1-index], input[index]
+	}
+	return output
+}
+func reverseInt(itemsValue reflect.Value) interface{}{
+	input := itemsValue.Interface().([]int)
+	len := len(input)
+	output := make([]int, len)
+	for index := 0; index < (len/2)+1; index++ {
+		output[index], output[len-1-index] = input[len-1-index], input[index]
+	}
+	return output
+}
+
+func reverseIntPtr(itemsValue reflect.Value) interface{}{
+	input := itemsValue.Interface().([]*int)
+	len := len(input)
+	output := make([]*int, len)
+	for index := 0; index < (len/2)+1; index++ {
+		output[index], output[len-1-index] = input[len-1-index], input[index]
+	}
+	return output
+}
+func reverseInt8(itemsValue reflect.Value) interface{}{
+	input := itemsValue.Interface().([]int8)
+	len := len(input)
+	output := make([]int8, len)
+	for index := 0; index < (len/2)+1; index++ {
+		output[index], output[len-1-index] = input[len-1-index], input[index]
+	}
+	return output
+}
+
+func reverseInt8Ptr(itemsValue reflect.Value) interface{}{
+	input := itemsValue.Interface().([]*int8)
+	len := len(input)
+	output := make([]*int8, len)
+	for index := 0; index < (len/2)+1; index++ {
+		output[index], output[len-1-index] = input[len-1-index], input[index]
+	}
+	return output
+}
+func reverseInt16(itemsValue reflect.Value) interface{}{
+	input := itemsValue.Interface().([]int16)
+	len := len(input)
+	output := make([]int16, len)
+	for index := 0; index < (len/2)+1; index++ {
+		output[index], output[len-1-index] = input[len-1-index], input[index]
+	}
+	return output
+}
+
+func reverseInt16Ptr(itemsValue reflect.Value) interface{}{
+	input := itemsValue.Interface().([]*int16)
+	len := len(input)
+	output := make([]*int16, len)
+	for index := 0; index < (len/2)+1; index++ {
+		output[index], output[len-1-index] = input[len-1-index], input[index]
+	}
+	return output
+}
+func reverseInt32(itemsValue reflect.Value) interface{}{
+	input := itemsValue.Interface().([]int32)
+	len := len(input)
+	output := make([]int32, len)
+	for index := 0; index < (len/2)+1; index++ {
+		output[index], output[len-1-index] = input[len-1-index], input[index]
+	}
+	return output
+}
+
+func reverseInt32Ptr(itemsValue reflect.Value) interface{}{
+	input := itemsValue.Interface().([]*int32)
+	len := len(input)
+	output := make([]*int32, len)
+	for index := 0; index < (len/2)+1; index++ {
+		output[index], output[len-1-index] = input[len-1-index], input[index]
+	}
+	return output
+}
+func reverseInt64(itemsValue reflect.Value) interface{}{
+	input := itemsValue.Interface().([]int64)
+	len := len(input)
+	output := make([]int64, len)
+	for index := 0; index < (len/2)+1; index++ {
+		output[index], output[len-1-index] = input[len-1-index], input[index]
+	}
+	return output
+}
+
+func reverseInt64Ptr(itemsValue reflect.Value) interface{}{
+	input := itemsValue.Interface().([]*int64)
+	len := len(input)
+	output := make([]*int64, len)
+	for index := 0; index < (len/2)+1; index++ {
+		output[index], output[len-1-index] = input[len-1-index], input[index]
+	}
+	return output
+}
+func reverseUint(itemsValue reflect.Value) interface{}{
+	input := itemsValue.Interface().([]uint)
+	len := len(input)
+	output := make([]uint, len)
+	for index := 0; index < (len/2)+1; index++ {
+		output[index], output[len-1-index] = input[len-1-index], input[index]
+	}
+	return output
+}
+
+func reverseUintPtr(itemsValue reflect.Value) interface{}{
+	input := itemsValue.Interface().([]*uint)
+	len := len(input)
+	output := make([]*uint, len)
+	for index := 0; index < (len/2)+1; index++ {
+		output[index], output[len-1-index] = input[len-1-index], input[index]
+	}
+	return output
+}
+func reverseUint8(itemsValue reflect.Value) interface{}{
+	input := itemsValue.Interface().([]uint8)
+	len := len(input)
+	output := make([]uint8, len)
+	for index := 0; index < (len/2)+1; index++ {
+		output[index], output[len-1-index] = input[len-1-index], input[index]
+	}
+	return output
+}
+
+func reverseUint8Ptr(itemsValue reflect.Value) interface{}{
+	input := itemsValue.Interface().([]*uint8)
+	len := len(input)
+	output := make([]*uint8, len)
+	for index := 0; index < (len/2)+1; index++ {
+		output[index], output[len-1-index] = input[len-1-index], input[index]
+	}
+	return output
+}
+func reverseUint16(itemsValue reflect.Value) interface{}{
+	input := itemsValue.Interface().([]uint16)
+	len := len(input)
+	output := make([]uint16, len)
+	for index := 0; index < (len/2)+1; index++ {
+		output[index], output[len-1-index] = input[len-1-index], input[index]
+	}
+	return output
+}
+
+func reverseUint16Ptr(itemsValue reflect.Value) interface{}{
+	input := itemsValue.Interface().([]*uint16)
+	len := len(input)
+	output := make([]*uint16, len)
+	for index := 0; index < (len/2)+1; index++ {
+		output[index], output[len-1-index] = input[len-1-index], input[index]
+	}
+	return output
+}
+func reverseUint32(itemsValue reflect.Value) interface{}{
+	input := itemsValue.Interface().([]uint32)
+	len := len(input)
+	output := make([]uint32, len)
+	for index := 0; index < (len/2)+1; index++ {
+		output[index], output[len-1-index] = input[len-1-index], input[index]
+	}
+	return output
+}
+
+func reverseUint32Ptr(itemsValue reflect.Value) interface{}{
+	input := itemsValue.Interface().([]*uint32)
+	len := len(input)
+	output := make([]*uint32, len)
+	for index := 0; index < (len/2)+1; index++ {
+		output[index], output[len-1-index] = input[len-1-index], input[index]
+	}
+	return output
+}
+func reverseUint64(itemsValue reflect.Value) interface{}{
+	input := itemsValue.Interface().([]uint64)
+	len := len(input)
+	output := make([]uint64, len)
+	for index := 0; index < (len/2)+1; index++ {
+		output[index], output[len-1-index] = input[len-1-index], input[index]
+	}
+	return output
+}
+
+func reverseUint64Ptr(itemsValue reflect.Value) interface{}{
+	input := itemsValue.Interface().([]*uint64)
+	len := len(input)
+	output := make([]*uint64, len)
+	for index := 0; index < (len/2)+1; index++ {
+		output[index], output[len-1-index] = input[len-1-index], input[index]
+	}
+	return output
+}
+func reverseFloat32(itemsValue reflect.Value) interface{}{
+	input := itemsValue.Interface().([]float32)
+	len := len(input)
+	output := make([]float32, len)
+	for index := 0; index < (len/2)+1; index++ {
+		output[index], output[len-1-index] = input[len-1-index], input[index]
+	}
+	return output
+}
+
+func reverseFloat32Ptr(itemsValue reflect.Value) interface{}{
+	input := itemsValue.Interface().([]*float32)
+	len := len(input)
+	output := make([]*float32, len)
+	for index := 0; index < (len/2)+1; index++ {
+		output[index], output[len-1-index] = input[len-1-index], input[index]
+	}
+	return output
+}
+func reverseFloat64(itemsValue reflect.Value) interface{}{
+	input := itemsValue.Interface().([]float64)
+	len := len(input)
+	output := make([]float64, len)
+	for index := 0; index < (len/2)+1; index++ {
+		output[index], output[len-1-index] = input[len-1-index], input[index]
+	}
+	return output
+}
+
+func reverseFloat64Ptr(itemsValue reflect.Value) interface{}{
+	input := itemsValue.Interface().([]*float64)
+	len := len(input)
+	output := make([]*float64, len)
+	for index := 0; index < (len/2)+1; index++ {
+		output[index], output[len-1-index] = input[len-1-index], input[index]
+	}
+	return output
+}