code: ///////////////////////////////////////////////////////////////////////////
  //                   __                _      _   ________               //
  //                  / /   ____  ____ _(_)____/ | / / ____/               //
  //                 / /   / __ \/ __ `/ / ___/  |/ / / __                 //
  //                / /___/ /_/ / /_/ / / /__/ /|  / /_/ /                 //
  //               /_____/\____/\__, /_/\___/_/ |_/\____/                  //
  //                           /____/                                      //
  //                                                                       //
  //               The Next Generation Logic Library                       //
  //                                                                       //
  ///////////////////////////////////////////////////////////////////////////
  //                                                                       //
  //  Copyright 2015-20xx Christoph Zengler                                //
  //                                                                       //
  //  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.logicng.transformations;
  
  import static org.assertj.core.api.Assertions.assertThat;
  
  import org.junit.jupiter.api.BeforeEach;
  import org.junit.jupiter.api.Test;
  import org.logicng.TestWithExampleFormulas;
  import org.logicng.formulas.Formula;
  import org.logicng.formulas.FormulaFactory;
  import org.logicng.formulas.FormulaFactoryConfig;
  import org.logicng.io.parsers.ParserException;
  import org.logicng.io.parsers.PseudoBooleanParser;
  import org.logicng.transformations.cnf.TseitinTransformation;
  
  /**
   * Unit tests for {@link FormulaFactoryImporter}.
   * @version 2.0.0
   * @since 1.3.1
   */
  public class FormulaFactoryImporterTest extends TestWithExampleFormulas {
  
      private FormulaFactory myF;
      private FormulaFactory myG;
      private FormulaFactoryImporter importer;
  
      @BeforeEach
      public void initialize() {
          this.myF = this.f;
          this.myG = new FormulaFactory(FormulaFactoryConfig.builder().name("Factory G").build());
          this.importer = new FormulaFactoryImporter(this.myG);
      }
  
      @Test
      public void testSameFactory() {
          final FormulaFactoryImporter sameImporter = new FormulaFactoryImporter(this.myF);
          assertThat(this.NOT1.factory()).isSameAs(this.myF);
          assertThat(this.NOT2.factory()).isSameAs(this.myF);
          assertThat(sameImporter.apply(this.NOT1, false).factory()).isSameAs(this.myF);
          assertThat(sameImporter.apply(this.NOT2, false).factory()).isSameAs(this.myF);
          assertThat(sameImporter.apply(this.NOT1, false)).isEqualTo(this.NOT1);
          assertThat(sameImporter.apply(this.NOT2, false)).isEqualTo(this.NOT2);
      }
  
      @Test
      public void testConstants() {
          assertThat(this.TRUE.factory()).isSameAs(this.myF);
          assertThat(this.FALSE.factory()).isSameAs(this.myF);
          assertThat(imp(this.TRUE).factory()).isSameAs(this.myG);
          assertThat(imp(this.FALSE).factory()).isSameAs(this.myG);
          assertThat(imp(this.TRUE)).isEqualTo(this.TRUE);
          assertThat(imp(this.FALSE)).isEqualTo(this.FALSE);
      }
  
      @Test
      public void testLiteral() {
          assertThat(this.A.factory()).isSameAs(this.myF);
          assertThat(this.NA.factory()).isSameAs(this.myF);
          assertThat(imp(this.A).factory()).isSameAs(this.myG);
          assertThat(imp(this.NA).factory()).isSameAs(this.myG);
          assertThat(imp(this.A)).isEqualTo(this.A);
          assertThat(imp(this.NA)).isEqualTo(this.NA);
          assertThat(this.myG.statistics().positiveLiterals()).isEqualTo(1);
          assertThat(this.myG.statistics().negativeLiterals()).isEqualTo(1);
      }
  
      @Test
      public void testNot() {
          assertThat(this.NOT1.factory()).isSameAs(this.myF);
          assertThat(this.NOT2.factory()).isSameAs(this.myF);
          assertThat(imp(this.NOT1).factory()).isSameAs(this.myG);
          assertThat(imp(this.NOT2).factory()).isSameAs(this.myG);
          assertThat(imp(this.NOT1)).isEqualTo(this.NOT1);
          assertThat(imp(this.NOT2)).isEqualTo(this.NOT2);
          assertThat(this.myG.statistics().positiveLiterals()).isEqualTo(4);
          assertThat(this.myG.statistics().negativeLiterals()).isEqualTo(0);
          assertThat(this.myG.statistics().conjunctions2()).isEqualTo(1);
          assertThat(this.myG.statistics().disjunctions2()).isEqualTo(1);
          assertThat(this.myG.statistics().negations()).isEqualTo(2);
      }
  
      @Test
      public void testImplication() {
          assertThat(this.IMP1.factory()).isSameAs(this.myF);
          assertThat(this.IMP2.factory()).isSameAs(this.myF);
          assertThat(this.IMP3.factory()).isSameAs(this.myF);
          assertThat(this.IMP4.factory()).isSameAs(this.myF);
          assertThat(imp(this.IMP1).factory()).isSameAs(this.myG);
          assertThat(imp(this.IMP2).factory()).isSameAs(this.myG);
          assertThat(imp(this.IMP3).factory()).isSameAs(this.myG);
          assertThat(imp(this.IMP4).factory()).isSameAs(this.myG);
          assertThat(imp(this.IMP1)).isEqualTo(this.IMP1);
          assertThat(imp(this.IMP2)).isEqualTo(this.IMP2);
          assertThat(imp(this.IMP3)).isEqualTo(this.IMP3);
          assertThat(imp(this.IMP4)).isEqualTo(this.IMP4);
          assertThat(this.myG.statistics().positiveLiterals()).isEqualTo(4);
          assertThat(this.myG.statistics().negativeLiterals()).isEqualTo(4);
          assertThat(this.myG.statistics().conjunctions2()).isEqualTo(1);
          assertThat(this.myG.statistics().disjunctions2()).isEqualTo(1);
          assertThat(this.myG.statistics().negations()).isEqualTo(0);
          assertThat(this.myG.statistics().implications()).isEqualTo(4);
          assertThat(this.myG.statistics().equivalences()).isEqualTo(2);
      }
  
      @Test
      public void testEquivalence() {
          assertThat(this.EQ1.factory()).isSameAs(this.myF);
          assertThat(this.EQ2.factory()).isSameAs(this.myF);
          assertThat(this.EQ3.factory()).isSameAs(this.myF);
          assertThat(this.EQ4.factory()).isSameAs(this.myF);
          assertThat(imp(this.EQ1).factory()).isSameAs(this.myG);
          assertThat(imp(this.EQ2).factory()).isSameAs(this.myG);
          assertThat(imp(this.EQ3).factory()).isSameAs(this.myG);
          assertThat(imp(this.EQ4).factory()).isSameAs(this.myG);
          assertThat(imp(this.EQ1)).isEqualTo(this.EQ1);
          assertThat(imp(this.EQ2)).isEqualTo(this.EQ2);
          assertThat(imp(this.EQ3)).isEqualTo(this.EQ3);
          assertThat(imp(this.EQ4)).isEqualTo(this.EQ4);
          assertThat(this.myG.statistics().positiveLiterals()).isEqualTo(4);
          assertThat(this.myG.statistics().negativeLiterals()).isEqualTo(2);
          assertThat(this.myG.statistics().conjunctions2()).isEqualTo(1);
          assertThat(this.myG.statistics().disjunctions2()).isEqualTo(1);
          assertThat(this.myG.statistics().negations()).isEqualTo(0);
          assertThat(this.myG.statistics().implications()).isEqualTo(2);
          assertThat(this.myG.statistics().equivalences()).isEqualTo(4);
      }
  
      @Test
      public void testOr() {
          assertThat(this.OR1.factory()).isSameAs(this.myF);
          assertThat(this.OR2.factory()).isSameAs(this.myF);
          assertThat(this.OR3.factory()).isSameAs(this.myF);
          assertThat(imp(this.OR1).factory()).isSameAs(this.myG);
          assertThat(imp(this.OR2).factory()).isSameAs(this.myG);
          assertThat(imp(this.OR3).factory()).isSameAs(this.myG);
          assertThat(imp(this.OR1)).isEqualTo(this.OR1);
          assertThat(imp(this.OR2)).isEqualTo(this.OR2);
          assertThat(imp(this.OR3)).isEqualTo(this.OR3);
          assertThat(this.myG.statistics().positiveLiterals()).isEqualTo(4);
          assertThat(this.myG.statistics().negativeLiterals()).isEqualTo(4);
          assertThat(this.myG.statistics().conjunctions2()).isEqualTo(2);
          assertThat(this.myG.statistics().disjunctions2()).isEqualTo(3);
          assertThat(this.myG.statistics().negations()).isEqualTo(0);
          assertThat(this.myG.statistics().implications()).isEqualTo(0);
          assertThat(this.myG.statistics().equivalences()).isEqualTo(0);
      }
  
      @Test
      public void testAnd() {
          assertThat(this.AND1.factory()).isSameAs(this.myF);
          assertThat(this.AND2.factory()).isSameAs(this.myF);
          assertThat(this.AND3.factory()).isSameAs(this.myF);
          assertThat(imp(this.AND1).factory()).isSameAs(this.myG);
          assertThat(imp(this.AND2).factory()).isSameAs(this.myG);
          assertThat(imp(this.AND3).factory()).isSameAs(this.myG);
          assertThat(imp(this.AND1)).isEqualTo(this.AND1);
          assertThat(imp(this.AND2)).isEqualTo(this.AND2);
          assertThat(imp(this.AND3)).isEqualTo(this.AND3);
          assertThat(this.myG.statistics().positiveLiterals()).isEqualTo(4);
          assertThat(this.myG.statistics().negativeLiterals()).isEqualTo(4);
          assertThat(this.myG.statistics().conjunctions2()).isEqualTo(3);
          assertThat(this.myG.statistics().disjunctions2()).isEqualTo(2);
          assertThat(this.myG.statistics().negations()).isEqualTo(0);
          assertThat(this.myG.statistics().implications()).isEqualTo(0);
          assertThat(this.myG.statistics().equivalences()).isEqualTo(0);
      }
  
      @Test
      public void testPBC() {
          assertThat(this.PBC1.factory()).isSameAs(this.myF);
          assertThat(this.PBC2.factory()).isSameAs(this.myF);
          assertThat(this.PBC3.factory()).isSameAs(this.myF);
          assertThat(this.PBC4.factory()).isSameAs(this.myF);
          assertThat(this.PBC5.factory()).isSameAs(this.myF);
          assertThat(imp(this.PBC1).factory()).isSameAs(this.myG);
          assertThat(imp(this.PBC2).factory()).isSameAs(this.myG);
          assertThat(imp(this.PBC3).factory()).isSameAs(this.myG);
          assertThat(imp(this.PBC4).factory()).isSameAs(this.myG);
          assertThat(imp(this.PBC5).factory()).isSameAs(this.myG);
          assertThat(imp(this.PBC1)).isEqualTo(this.PBC1);
          assertThat(imp(this.PBC2)).isEqualTo(this.PBC2);
          assertThat(imp(this.PBC3)).isEqualTo(this.PBC3);
          assertThat(imp(this.PBC4)).isEqualTo(this.PBC4);
          assertThat(imp(this.PBC5)).isEqualTo(this.PBC5);
          assertThat(this.myG.statistics().positiveLiterals()).isEqualTo(3);
          assertThat(this.myG.statistics().negativeLiterals()).isEqualTo(0);
          assertThat(this.myG.statistics().conjunctions2()).isEqualTo(0);
          assertThat(this.myG.statistics().disjunctions2()).isEqualTo(0);
          assertThat(this.myG.statistics().negations()).isEqualTo(0);
          assertThat(this.myG.statistics().implications()).isEqualTo(0);
          assertThat(this.myG.statistics().equivalences()).isEqualTo(0);
      }
  
      @Test
      public void testAdjustCounters() throws ParserException {
          final FormulaFactory f = new FormulaFactory(FormulaFactoryConfig.builder().name("Factory").build());
          final PseudoBooleanParser p = new PseudoBooleanParser(f);
          final Formula cc = p.parse("A + B + C + D + E <= 2").cnf();
          final Formula pbc = p.parse("2*A + -2*B + 3*C + D + 2*E <= 3").cnf();
          final Formula cnf = p.parse("A & B & C | C & D & ~A").transform(new TseitinTransformation(0));
  
          final FormulaFactory g = new FormulaFactory();
          g.newCNFVariable();
          g.newCNFVariable();
          g.newCCVariable();
          g.newCCVariable();
          g.newCCVariable();
          g.newPBVariable();
          g.newPBVariable();
          g.newPBVariable();
          g.importFormula(cc);
          g.importFormula(pbc);
          g.importFormula(cnf);
          assertThat(g.statistics().cnfCounter()).isEqualTo(2);
          assertThat(g.statistics().ccCounter()).isEqualTo(13);
          assertThat(g.statistics().pbCounter()).isEqualTo(25);
      }
  
      /**
       * Imports the given formula in the new formula factory.
       * @param formula the formula to import
       * @return the imported formula
       */
      private Formula imp(final Formula formula) {
          return this.importer.apply(formula, false);
      }
  }
  