Add some basic benchmarks to compare to native

Currently only benchmarking `Any`, `Select` and `Sort

benchmarks/dummy_obj.go

@@ -0,0 +1,11 @@
+package benchmarks
+
+// +gen * slice:"Any,Select[*dummyDestinationSelectObject],SortBy"
+type dummyObject struct {
+	Name string
+	Num  int
+}
+
+type dummyDestinationSelectObject struct {
+	Name string
+}

benchmarks/dummy_obj_test.go

@@ -0,0 +1,70 @@
+package benchmarks
+
+import (
+	"fmt"
+	"testing"
+)
+
+var (
+	dummyObjects      dummyObjectSlice
+	globalBoolResult  bool
+	globalSliceResult []*dummyDestinationSelectObject
+	globalSliceResul2 []*dummyObject
+)
+
+//Any
+func BenchmarkDummyObjAny_Generics(b *testing.B) {
+	for n := 0; n < b.N; n++ {
+		globalBoolResult = dummyObjects.Any(func(d *dummyObject) bool { return d.Num > 10000 })
+	}
+}
+
+func BenchmarkDummyObjAny_NativeLoop(b *testing.B) {
+	for n := 0; n < b.N; n++ {
+		any := false
+		for _, d := range dummyObjects {
+			if d.Num > 10000 {
+				any = true
+				break
+			}
+		}
+		globalBoolResult = any
+	}
+}
+
+//Select
+func BenchmarkDummyObjSelect_Generics(b *testing.B) {
+	for n := 0; n < b.N; n++ {
+		globalSliceResult = dummyObjects.SelectDummyDestinationSelectObject(func(d *dummyObject) *dummyDestinationSelectObject { return &dummyDestinationSelectObject{d.Name} })
+		globalBoolResult = len(globalSliceResult) == len(dummyObjects)
+	}
+}
+
+func BenchmarkDummyObjSelect_NativeLoop(b *testing.B) {
+	for n := 0; n < b.N; n++ {
+		globalSliceResult = []*dummyDestinationSelectObject{}
+		for _, d := range dummyObjects {
+			globalSliceResult = append(globalSliceResult, &dummyDestinationSelectObject{d.Name})
+		}
+		globalBoolResult = len(globalSliceResult) == len(dummyObjects)
+	}
+}
+
+//SortBy
+func BenchmarkDummyObjSortBy_Generics(b *testing.B) {
+	for n := 0; n < b.N; n++ {
+		globalSliceResul2 = dummyObjects.SortBy(func(a *dummyObject, b *dummyObject) (isLess bool) { return a.Num%3 == 0 })
+	}
+}
+
+/*TODO:
+func BenchmarkDummyObjSortBy_NativeLoop(b *testing.B) {
+
+}*/
+
+func init() {
+	dummyObjects = dummyObjectSlice([]*dummyObject{})
+	for i := 0; i < 10000; i++ {
+		dummyObjects = append(dummyObjects, &dummyObject{fmt.Sprintf("Name %d", i), i})
+	}
+}

benchmarks/dummyobject_slice.go

@@ -0,0 +1,219 @@
+// Generated by: gen
+// TypeWriter: slice
+// Directive: +gen on *dummyObject
+
+package benchmarks
+
+// Sort implementation is a modification of http://golang.org/pkg/sort/#Sort
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found at http://golang.org/LICENSE.
+
+// dummyObjectSlice is a slice of type *dummyObject. Use it where you would use []*dummyObject.
+type dummyObjectSlice []*dummyObject
+
+// Any verifies that one or more elements of dummyObjectSlice return true for the passed func. See: http://clipperhouse.github.io/gen/#Any
+func (rcv dummyObjectSlice) Any(fn func(*dummyObject) bool) bool {
+	for _, v := range rcv {
+		if fn(v) {
+			return true
+		}
+	}
+	return false
+}
+
+// SelectDummyDestinationSelectObject projects a slice of *dummyDestinationSelectObject from dummyObjectSlice, typically called a map in other frameworks. See: http://clipperhouse.github.io/gen/#Select
+func (rcv dummyObjectSlice) SelectDummyDestinationSelectObject(fn func(*dummyObject) *dummyDestinationSelectObject) (result []*dummyDestinationSelectObject) {
+	for _, v := range rcv {
+		result = append(result, fn(v))
+	}
+	return
+}
+
+// SortBy returns a new ordered dummyObjectSlice, determined by a func defining ‘less’. See: http://clipperhouse.github.io/gen/#SortBy
+func (rcv dummyObjectSlice) SortBy(less func(*dummyObject, *dummyObject) bool) dummyObjectSlice {
+	result := make(dummyObjectSlice, len(rcv))
+	copy(result, rcv)
+	// Switch to heapsort if depth of 2*ceil(lg(n+1)) is reached.
+	n := len(result)
+	maxDepth := 0
+	for i := n; i > 0; i >>= 1 {
+		maxDepth++
+	}
+	maxDepth *= 2
+	quickSortdummyObjectSlice(result, less, 0, n, maxDepth)
+	return result
+}
+
+// Sort implementation based on http://golang.org/pkg/sort/#Sort, see top of this file
+
+func swapdummyObjectSlice(rcv dummyObjectSlice, a, b int) {
+	rcv[a], rcv[b] = rcv[b], rcv[a]
+}
+
+// Insertion sort
+func insertionSortdummyObjectSlice(rcv dummyObjectSlice, less func(*dummyObject, *dummyObject) bool, a, b int) {
+	for i := a + 1; i < b; i++ {
+		for j := i; j > a && less(rcv[j], rcv[j-1]); j-- {
+			swapdummyObjectSlice(rcv, j, j-1)
+		}
+	}
+}
+
+// siftDown implements the heap property on rcv[lo, hi).
+// first is an offset into the array where the root of the heap lies.
+func siftDowndummyObjectSlice(rcv dummyObjectSlice, less func(*dummyObject, *dummyObject) bool, lo, hi, first int) {
+	root := lo
+	for {
+		child := 2*root + 1
+		if child >= hi {
+			break
+		}
+		if child+1 < hi && less(rcv[first+child], rcv[first+child+1]) {
+			child++
+		}
+		if !less(rcv[first+root], rcv[first+child]) {
+			return
+		}
+		swapdummyObjectSlice(rcv, first+root, first+child)
+		root = child
+	}
+}
+
+func heapSortdummyObjectSlice(rcv dummyObjectSlice, less func(*dummyObject, *dummyObject) bool, a, b int) {
+	first := a
+	lo := 0
+	hi := b - a
+
+	// Build heap with greatest element at top.
+	for i := (hi - 1) / 2; i >= 0; i-- {
+		siftDowndummyObjectSlice(rcv, less, i, hi, first)
+	}
+
+	// Pop elements, largest first, into end of rcv.
+	for i := hi - 1; i >= 0; i-- {
+		swapdummyObjectSlice(rcv, first, first+i)
+		siftDowndummyObjectSlice(rcv, less, lo, i, first)
+	}
+}
+
+// Quicksort, following Bentley and McIlroy,
+// Engineering a Sort Function, SP&E November 1993.
+
+// medianOfThree moves the median of the three values rcv[a], rcv[b], rcv[c] into rcv[a].
+func medianOfThreedummyObjectSlice(rcv dummyObjectSlice, less func(*dummyObject, *dummyObject) bool, a, b, c int) {
+	m0 := b
+	m1 := a
+	m2 := c
+	// bubble sort on 3 elements
+	if less(rcv[m1], rcv[m0]) {
+		swapdummyObjectSlice(rcv, m1, m0)
+	}
+	if less(rcv[m2], rcv[m1]) {
+		swapdummyObjectSlice(rcv, m2, m1)
+	}
+	if less(rcv[m1], rcv[m0]) {
+		swapdummyObjectSlice(rcv, m1, m0)
+	}
+	// now rcv[m0] <= rcv[m1] <= rcv[m2]
+}
+
+func swapRangedummyObjectSlice(rcv dummyObjectSlice, a, b, n int) {
+	for i := 0; i < n; i++ {
+		swapdummyObjectSlice(rcv, a+i, b+i)
+	}
+}
+
+func doPivotdummyObjectSlice(rcv dummyObjectSlice, less func(*dummyObject, *dummyObject) bool, lo, hi int) (midlo, midhi int) {
+	m := lo + (hi-lo)/2 // Written like this to avoid integer overflow.
+	if hi-lo > 40 {
+		// Tukey's Ninther, median of three medians of three.
+		s := (hi - lo) / 8
+		medianOfThreedummyObjectSlice(rcv, less, lo, lo+s, lo+2*s)
+		medianOfThreedummyObjectSlice(rcv, less, m, m-s, m+s)
+		medianOfThreedummyObjectSlice(rcv, less, hi-1, hi-1-s, hi-1-2*s)
+	}
+	medianOfThreedummyObjectSlice(rcv, less, lo, m, hi-1)
+
+	// Invariants are:
+	//	rcv[lo] = pivot (set up by ChoosePivot)
+	//	rcv[lo <= i < a] = pivot
+	//	rcv[a <= i < b] < pivot
+	//	rcv[b <= i < c] is unexamined
+	//	rcv[c <= i < d] > pivot
+	//	rcv[d <= i < hi] = pivot
+	//
+	// Once b meets c, can swap the "= pivot" sections
+	// into the middle of the slice.
+	pivot := lo
+	a, b, c, d := lo+1, lo+1, hi, hi
+	for {
+		for b < c {
+			if less(rcv[b], rcv[pivot]) { // rcv[b] < pivot
+				b++
+			} else if !less(rcv[pivot], rcv[b]) { // rcv[b] = pivot
+				swapdummyObjectSlice(rcv, a, b)
+				a++
+				b++
+			} else {
+				break
+			}
+		}
+		for b < c {
+			if less(rcv[pivot], rcv[c-1]) { // rcv[c-1] > pivot
+				c--
+			} else if !less(rcv[c-1], rcv[pivot]) { // rcv[c-1] = pivot
+				swapdummyObjectSlice(rcv, c-1, d-1)
+				c--
+				d--
+			} else {
+				break
+			}
+		}
+		if b >= c {
+			break
+		}
+		// rcv[b] > pivot; rcv[c-1] < pivot
+		swapdummyObjectSlice(rcv, b, c-1)
+		b++
+		c--
+	}
+
+	min := func(a, b int) int {
+		if a < b {
+			return a
+		}
+		return b
+	}
+
+	n := min(b-a, a-lo)
+	swapRangedummyObjectSlice(rcv, lo, b-n, n)
+
+	n = min(hi-d, d-c)
+	swapRangedummyObjectSlice(rcv, c, hi-n, n)
+
+	return lo + b - a, hi - (d - c)
+}
+
+func quickSortdummyObjectSlice(rcv dummyObjectSlice, less func(*dummyObject, *dummyObject) bool, a, b, maxDepth int) {
+	for b-a > 7 {
+		if maxDepth == 0 {
+			heapSortdummyObjectSlice(rcv, less, a, b)
+			return
+		}
+		maxDepth--
+		mlo, mhi := doPivotdummyObjectSlice(rcv, less, a, b)
+		// Avoiding recursion on the larger subproblem guarantees
+		// a stack depth of at most lg(b-a).
+		if mlo-a < b-mhi {
+			quickSortdummyObjectSlice(rcv, less, a, mlo, maxDepth)
+			a = mhi // i.e., quickSortdummyObjectSlice(rcv, mhi, b)
+		} else {
+			quickSortdummyObjectSlice(rcv, less, mhi, b, maxDepth)
+			b = mlo // i.e., quickSortdummyObjectSlice(rcv, a, mlo)
+		}
+	}
+	if b-a > 1 {
+		insertionSortdummyObjectSlice(rcv, less, a, b)
+	}
+}