From 59011fcde6586150148792e3309cd3e15fe9e74a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Kamil=20=C5=9Aliwak?= <kamil.sliwak@codepoets.it>
Date: Wed, 11 Mar 2020 23:45:46 +0100
Subject: [PATCH] [yul-phaser] Mutations: Add mutationSequence()

---
 test/yulPhaser/Mutations.cpp  | 33 +++++++++++++++++++++++++++++++++
 tools/yulPhaser/Mutations.cpp | 12 ++++++++++++
 tools/yulPhaser/Mutations.h   |  3 +++
 3 files changed, 48 insertions(+)

diff --git a/test/yulPhaser/Mutations.cpp b/test/yulPhaser/Mutations.cpp
index d98fa7604..33c623f84 100644
--- a/test/yulPhaser/Mutations.cpp
+++ b/test/yulPhaser/Mutations.cpp
@@ -212,6 +212,39 @@ BOOST_AUTO_TEST_CASE(alternativeMutations_should_always_choose_second_mutation_i
 		BOOST_TEST(mutation(chromosome) == Chromosome("f"));
 }
 
+BOOST_AUTO_TEST_CASE(mutationSequence_should_apply_all_mutations)
+{
+	Chromosome chromosome("aaaaa");
+	function<Mutation> mutation = mutationSequence({
+		geneSubstitution(3, Chromosome("g").optimisationSteps()[0]),
+		geneSubstitution(2, Chromosome("f").optimisationSteps()[0]),
+		geneSubstitution(1, Chromosome("c").optimisationSteps()[0]),
+	});
+
+	BOOST_TEST(mutation(chromosome) == Chromosome("acfga"));
+}
+
+BOOST_AUTO_TEST_CASE(mutationSequence_apply_mutations_in_the_order_they_are_given)
+{
+	Chromosome chromosome("aa");
+	function<Mutation> mutation = mutationSequence({
+		geneSubstitution(0, Chromosome("g").optimisationSteps()[0]),
+		geneSubstitution(1, Chromosome("c").optimisationSteps()[0]),
+		geneSubstitution(0, Chromosome("f").optimisationSteps()[0]),
+		geneSubstitution(1, Chromosome("o").optimisationSteps()[0]),
+	});
+
+	BOOST_TEST(mutation(chromosome) == Chromosome("fo"));
+}
+
+BOOST_AUTO_TEST_CASE(mutationSequence_should_return_unmodified_chromosome_if_given_no_mutations)
+{
+	Chromosome chromosome("aa");
+	function<Mutation> mutation = mutationSequence({});
+
+	BOOST_TEST(mutation(chromosome) == chromosome);
+}
+
 BOOST_AUTO_TEST_CASE(randomPointCrossover_should_swap_chromosome_parts_at_random_point)
 {
 	function<Crossover> crossover = randomPointCrossover();
diff --git a/tools/yulPhaser/Mutations.cpp b/tools/yulPhaser/Mutations.cpp
index 9cf741707..98689a810 100644
--- a/tools/yulPhaser/Mutations.cpp
+++ b/tools/yulPhaser/Mutations.cpp
@@ -95,6 +95,18 @@ function<Mutation> phaser::alternativeMutations(
 	};
 }
 
+function<Mutation> phaser::mutationSequence(vector<function<Mutation>> _mutations)
+{
+	return [=](Chromosome const& _chromosome)
+	{
+		Chromosome mutatedChromosome = _chromosome;
+		for (size_t i = 0; i < _mutations.size(); ++i)
+			mutatedChromosome = _mutations[i](move(mutatedChromosome));
+
+		return mutatedChromosome;
+	};
+}
+
 namespace
 {
 
diff --git a/tools/yulPhaser/Mutations.h b/tools/yulPhaser/Mutations.h
index 5554a1d2d..d545aa093 100644
--- a/tools/yulPhaser/Mutations.h
+++ b/tools/yulPhaser/Mutations.h
@@ -58,6 +58,9 @@ std::function<Mutation> alternativeMutations(
 	std::function<Mutation> _mutation2
 );
 
+/// Creates a mutation operator that sequentially applies all the operators given in @a _mutations.
+std::function<Mutation> mutationSequence(std::vector<std::function<Mutation>> _mutations);
+
 // CROSSOVER
 
 /// Creates a crossover operator that randomly selects a number between 0 and 1 and uses it as the