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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
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package com.oracle.svm.hosted.lambda;

import java.util.HashSet;
import java.util.List;
import java.util.Set;

import org.graalvm.compiler.java.LambdaUtils;

import com.oracle.graal.pointsto.meta.AnalysisType;
import com.oracle.svm.core.SubstrateUtil;
import com.oracle.svm.core.feature.InternalFeature;
import com.oracle.svm.core.feature.AutomaticallyRegisteredFeature;
import com.oracle.svm.hosted.FeatureImpl.AfterAnalysisAccessImpl;
import com.oracle.svm.hosted.FeatureImpl.DuringSetupAccessImpl;

/**
 * @see LambdaProxyRenamingSubstitutionProcessor
 */
@AutomaticallyRegisteredFeature
final class StableLambdaProxyNameFeature implements InternalFeature {

    @Override
    public void duringSetup(DuringSetupAccess a) {
        DuringSetupAccessImpl access = (DuringSetupAccessImpl) a;
        LambdaProxyRenamingSubstitutionProcessor lSubst = new LambdaProxyRenamingSubstitutionProcessor(access.getBigBang());
        access.registerSubstitutionProcessor(lSubst);
    }

    @Override
    public void afterAnalysis(AfterAnalysisAccess access) {
        assert checkLambdaNames(((AfterAnalysisAccessImpl) access).getUniverse().getTypes());
    }

    private static boolean checkLambdaNames(List<AnalysisType> types) {
        if (!SubstrateUtil.assertionsEnabled()) {
            throw new AssertionError("Expensive check: should only run with assertions enabled.");
        }
        /* There should be no random lambda names visible to the analysis. */
        if (types.stream().anyMatch(type -> LambdaUtils.isLambdaType(type) && type.getWrapped().getClass() != LambdaSubstitutionType.class)) {
            throw new AssertionError("All lambda proxies should be substituted.");
        }

        /* Lambda names should be unique. */
        Set<String> lambdaNames = new HashSet<>();
        types.stream()
                        .map(AnalysisType::getName)
                        .filter(x -> x.contains(LambdaUtils.LAMBDA_CLASS_NAME_SUBSTRING))
                        .forEach(name -> {
                            if (lambdaNames.contains(name)) {
                                throw new AssertionError("Duplicate lambda name: " + name);
                            }
                            lambdaNames.add(name);
                        });
        return true;
    }
}
