test

binary/genome_test.go

@@ -1,4 +1,69 @@
 // Copyright (c) Roman Atachiants and contributors. All rights reserved.
 // Licensed under the MIT license. See LICENSE file in the project root for details.
 
-package binary
+package binary_test
+
+import (
+	"testing"
+
+	"github.com/kelindar/evolve"
+	"github.com/kelindar/evolve/binary"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestEvolve(t *testing.T) {
+	const target = "abc"
+	const n = 200
+	population := make([]evolve.Evolver, 0, n)
+	for i := 0; i < n; i++ {
+		population = append(population, new(text))
+	}
+
+	fit := fitnessFor(target)
+	pop := evolve.New(population, fit, binary.Make(len(target)))
+
+	// Evolve
+	i, last := 0, ""
+	for ; i < 100000; i++ {
+		pop.Evolve()
+		if last = toString(pop.Fittest().Genome()); last == target {
+			break
+		}
+	}
+
+	assert.Equal(t, target, toString(pop.Fittest().Genome()))
+}
+
+// fitnessFor returns a fitness function for a string
+func fitnessFor(text string) evolve.Fitness {
+	target := []byte(text)
+	return func(v evolve.Evolver) float32 {
+		var score float32
+		genome := v.Genome().(*binary.Genome)
+		for i, v := range *genome {
+			if v == target[i] {
+				score++
+			}
+		}
+		return score / float32(len(target))
+	}
+}
+
+// Text represents a text with a dna (text itself in this case)
+type text struct {
+	dna evolve.Genome
+}
+
+// Genome returns the genome
+func (t *text) Genome() evolve.Genome {
+	return t.dna
+}
+
+// Evolve updates the genome
+func (t *text) Evolve(v evolve.Genome) {
+	t.dna = v
+}
+
+func toString(v evolve.Genome) string {
+	return string(*v.(*binary.Genome))
+}