1 files changed, 89 insertions, 0 deletions
diff --git a/src/main/java/com/code_intelligence/jazzer/mutation/combinator/PostComposedMutator.java b/src/main/java/com/code_intelligence/jazzer/mutation/combinator/PostComposedMutator.java
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+++ b/src/main/java/com/code_intelligence/jazzer/mutation/combinator/PostComposedMutator.java
@@ -0,0 +1,89 @@
+/*
+ * Copyright 2023 Code Intelligence GmbH
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.code_intelligence.jazzer.mutation.combinator;
+
+import static java.util.Objects.requireNonNull;
+
+import com.code_intelligence.jazzer.mutation.api.Debuggable;
+import com.code_intelligence.jazzer.mutation.api.PseudoRandom;
+import com.code_intelligence.jazzer.mutation.api.SerializingMutator;
+import java.io.DataInputStream;
+import java.io.DataOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.util.function.Function;
+import java.util.function.Predicate;
+import net.jodah.typetools.TypeResolver;
+
+abstract class PostComposedMutator<T, R> extends SerializingMutator<R> {
+  private final SerializingMutator<T> mutator;
+  private final Function<T, R> map;
+  private final Function<R, T> inverse;
+
+  PostComposedMutator(SerializingMutator<T> mutator, Function<T, R> map, Function<R, T> inverse) {
+    this.mutator = requireNonNull(mutator);
+    this.map = requireNonNull(map);
+    this.inverse = requireNonNull(inverse);
+  }
+
+  @Override
+  public R detach(R value) {
+    return map.apply(mutator.detach(inverse.apply(value)));
+  }
+
+  @Override
+  public final R init(PseudoRandom prng) {
+    return map.apply(mutator.init(prng));
+  }
+
+  @Override
+  public final R mutate(R value, PseudoRandom prng) {
+    return map.apply(mutator.mutate(inverse.apply(value), prng));
+  }
+
+  @Override
+  public R crossOver(R value, R otherValue, PseudoRandom prng) {
+    return map.apply(mutator.crossOver(inverse.apply(value), inverse.apply(otherValue), prng));
+  }
+
+  @Override
+  public final R read(DataInputStream in) throws IOException {
+    return map.apply(mutator.read(in));
+  }
+
+  @Override
+  public final void write(R value, DataOutputStream out) throws IOException {
+    mutator.write(inverse.apply(value), out);
+  }
+
+  @Override
+  public final R readExclusive(InputStream in) throws IOException {
+    return map.apply(mutator.readExclusive(in));
+  }
+
+  @Override
+  public final void writeExclusive(R value, OutputStream out) throws IOException {
+    mutator.writeExclusive(inverse.apply(value), out);
+  }
+
+  @Override
+  public String toDebugString(Predicate<Debuggable> isInCycle) {
+    Class<?> returnType = TypeResolver.resolveRawArguments(Function.class, map.getClass())[1];
+    return mutator.toDebugString(isInCycle) + " -> " + returnType.getSimpleName();
+  }
+}