org.pitest.mutationtest.engine.gregor.mutators.MethodCallMethodVisitor.java Source code

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Here is the source code for org.pitest.mutationtest.engine.gregor.mutators.MethodCallMethodVisitor.java

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/*
 * Copyright 2010 Henry Coles
 * 
 * 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 org.pitest.mutationtest.engine.gregor.mutators;

import static org.objectweb.asm.Opcodes.DCONST_0;
import static org.objectweb.asm.Opcodes.FCONST_0;
import static org.objectweb.asm.Opcodes.ICONST_0;
import static org.objectweb.asm.Opcodes.INVOKESTATIC;
import static org.objectweb.asm.Opcodes.LCONST_0;
import static org.objectweb.asm.Opcodes.POP;
import static org.objectweb.asm.Opcodes.POP2;

import java.util.HashMap;
import java.util.Map;

import org.objectweb.asm.MethodVisitor;
import org.objectweb.asm.Opcodes;
import org.objectweb.asm.Type;
import org.pitest.functional.F2;
import org.pitest.mutationtest.engine.MutationIdentifier;
import org.pitest.mutationtest.engine.gregor.MethodInfo;
import org.pitest.mutationtest.engine.gregor.MethodMutatorFactory;
import org.pitest.mutationtest.engine.gregor.MutationContext;

class MethodCallMethodVisitor extends MethodVisitor {

    private static final Map<Type, Integer> RETURN_TYPE_MAP = new HashMap<Type, Integer>();

    private final F2<String, String, Boolean> filter;
    private final MethodMutatorFactory factory;
    private final MutationContext context;
    private final MethodInfo methodInfo;

    static {
        RETURN_TYPE_MAP.put(Type.INT_TYPE, ICONST_0);
        RETURN_TYPE_MAP.put(Type.BOOLEAN_TYPE, ICONST_0);
        RETURN_TYPE_MAP.put(Type.BYTE_TYPE, ICONST_0);
        RETURN_TYPE_MAP.put(Type.CHAR_TYPE, ICONST_0);
        RETURN_TYPE_MAP.put(Type.SHORT_TYPE, ICONST_0);
        RETURN_TYPE_MAP.put(Type.LONG_TYPE, LCONST_0);
        RETURN_TYPE_MAP.put(Type.FLOAT_TYPE, FCONST_0);
        RETURN_TYPE_MAP.put(Type.DOUBLE_TYPE, DCONST_0);
    }

    public MethodCallMethodVisitor(final MethodInfo methodInfo, final MutationContext context,
            final MethodVisitor writer, final MethodMutatorFactory factory,
            final F2<String, String, Boolean> filter) {
        super(Opcodes.ASM5, writer);
        this.factory = factory;
        this.filter = filter;
        this.context = context;
        this.methodInfo = methodInfo;
    }

    @Override
    public void visitMethodInsn(final int opcode, final String owner, final String name, final String desc,
            boolean itf) {

        if (!this.filter.apply(name, desc) || isCallToSuperOrOwnConstructor(name, owner)) {
            this.mv.visitMethodInsn(opcode, owner, name, desc, itf);
        } else {
            final MutationIdentifier newId = this.context.registerMutation(this.factory,
                    "removed call to " + owner + "::" + name);

            if (this.context.shouldMutate(newId)) {

                popStack(desc, name);
                popThisIfNotStatic(opcode);
                putReturnValueOnStack(desc, name);

            } else {
                this.mv.visitMethodInsn(opcode, owner, name, desc, itf);
            }
        }

    }

    private boolean isCallToSuperOrOwnConstructor(final String name, final String owner) {
        return this.methodInfo.isConstructor() && MethodInfo.isConstructor(name)
                && (owner.equals(this.context.getClassInfo().getName())
                        || this.context.getClassInfo().getSuperName().equals(owner));
    }

    private void popThisIfNotStatic(final int opcode) {
        if (!isStatic(opcode)) {
            this.mv.visitInsn(POP);
        }
    }

    private void popStack(final String desc, final String name) {
        final Type[] argTypes = Type.getArgumentTypes(desc);
        for (int i = argTypes.length - 1; i >= 0; i--) {
            final Type argumentType = argTypes[i];
            if (argumentType.getSize() != 1) {
                this.mv.visitInsn(POP2);
            } else {
                this.mv.visitInsn(POP);
            }
        }

        if (MethodInfo.isConstructor(name)) {
            this.mv.visitInsn(POP);
        }
    }

    private static boolean isStatic(final int opcode) {
        return INVOKESTATIC == opcode;
    }

    private void putReturnValueOnStack(final String desc, final String name) {
        final Type returnType = Type.getReturnType(desc);
        if (!returnType.equals(Type.VOID_TYPE)) {
            final Integer opCode = RETURN_TYPE_MAP.get(returnType);
            if (opCode == null) {
                this.mv.visitInsn(Opcodes.ACONST_NULL);
            } else {
                this.mv.visitInsn(opCode);
            }
        } else if (MethodInfo.isConstructor(name)) {
            this.mv.visitInsn(Opcodes.ACONST_NULL);
        }
    }

}