Add simple unit tests

src/test/java/org/jabref/gui/autocompleter/SuggestionProvidersTest.java

@@ -0,0 +1,49 @@
+package org.jabref.gui.autocompleter;
+
+import org.jabref.logic.journals.JournalAbbreviationRepository;
+import org.jabref.model.database.BibDatabase;
+import org.jabref.model.entry.BibEntry;
+import org.jabref.model.entry.field.Field;
+import org.jabref.model.entry.field.FieldFactory;
+import org.jabref.model.entry.field.SpecialField;
+import org.jabref.model.entry.field.StandardField;
+
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertSame;
+import static org.mockito.Mockito.mock;
+
+class SuggestionProvidersTest {
+
+  @Test
+  void getForFieldTest() {
+      BibDatabase database = new BibDatabase();
+      JournalAbbreviationRepository abbreviationRepository = mock(JournalAbbreviationRepository.class);
+      BibEntry entry = new BibEntry();
+      Field personEntryField = StandardField.AUTHOR;
+      Field singleEntryField = StandardField.XREF;
+      Field multipleEntryField = StandardField.XDATA;
+      Field journalEntryField = StandardField.JOURNAL;
+      Field publisherEntryField = StandardField.PUBLISHER;
+      Field specialEntryField = SpecialField.PRINTED;
+      AutoCompletePreferences autoCompletePreferences = new AutoCompletePreferences(true, AutoCompleteFirstNameMode.BOTH, AutoCompletePreferences.NameFormat.BOTH, FieldFactory.parseFieldList(personEntryField.getName() + ";" + singleEntryField.getName() + ";" + multipleEntryField.getName() + ";" + journalEntryField.getName() + ";" + publisherEntryField.getName() + ";" + specialEntryField.getName()), null);
+      SuggestionProviders sp = new SuggestionProviders(database, abbreviationRepository, autoCompletePreferences);
+      SuggestionProviders empty = new SuggestionProviders();
+
+      entry.setField(personEntryField, "Goethe");
+      entry.setField(singleEntryField, "Single");
+      entry.setField(multipleEntryField, "Multiple");
+      entry.setField(journalEntryField, "Journal");
+      entry.setField(publisherEntryField, "Publisher");
+      entry.setField(specialEntryField, "2000");
+      database.insertEntry(entry);
+
+      assertSame("org.jabref.gui.autocompleter.EmptySuggestionProvider", empty.getForField(personEntryField).getClass().getName());
+      assertSame("org.jabref.gui.autocompleter.PersonNameSuggestionProvider", sp.getForField(personEntryField).getClass().getName());
+      assertSame("org.jabref.gui.autocompleter.BibEntrySuggestionProvider", sp.getForField(singleEntryField).getClass().getName());
+      assertSame("org.jabref.gui.autocompleter.BibEntrySuggestionProvider", sp.getForField(multipleEntryField).getClass().getName());
+      assertSame("org.jabref.gui.autocompleter.JournalsSuggestionProvider", sp.getForField(journalEntryField).getClass().getName());
+      assertSame("org.jabref.gui.autocompleter.JournalsSuggestionProvider", sp.getForField(publisherEntryField).getClass().getName());
+      assertSame("org.jabref.gui.autocompleter.WordSuggestionProvider", sp.getForField(specialEntryField).getClass().getName());
+  }
+}

src/test/java/org/jabref/logic/citationkeypattern/CitationKeyGeneratorTest.java

@@ -747,6 +747,9 @@ void testLastPage() {
         assertEquals("97", CitationKeyGenerator.lastPage("7,41,73--97"));
         assertEquals("97", CitationKeyGenerator.lastPage("7,41,97--73"));
         assertEquals("43", CitationKeyGenerator.lastPage("43+"));
+        assertEquals("0", CitationKeyGenerator.lastPage("00--0"));
+        assertEquals("1", CitationKeyGenerator.lastPage("1--1"));
+
     }
 
     @SuppressWarnings("ConstantConditions")

src/test/java/org/jabref/logic/citationstyle/CitationStyleCacheTest.java

@@ -0,0 +1,34 @@
+package org.jabref.logic.citationstyle;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import org.jabref.model.database.BibDatabase;
+import org.jabref.model.database.BibDatabaseContext;
+import org.jabref.model.entry.BibEntry;
+
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+
+class CitationStyleCacheTest {
+
+  private BibEntry bibEntry;
+  private List<BibEntry> entries;
+  private BibDatabase database;
+  private BibDatabaseContext databaseContext;
+  private CitationStyleCache csCache;
+
+  @Test
+  void getCitationForTest() {
+    BibEntry bibEntry = new BibEntry();
+    bibEntry.setCitationKey("test");
+    List<BibEntry> entries = new ArrayList<>();
+    entries.add(0, bibEntry);
+    BibDatabase database = new BibDatabase(entries);
+    BibDatabaseContext databaseContext = new BibDatabaseContext(database);
+    CitationStyleCache csCache = new CitationStyleCache(databaseContext);
+
+    assertNotNull(csCache.getCitationFor(bibEntry));
+  }
+}

src/test/java/org/jabref/logic/formatter/casechanger/UpperCaseFormatterTest.java

@@ -24,6 +24,9 @@ public void test() {
         assertEquals("UPPER", formatter.format("UPPER"));
         assertEquals("UPPER {lower}", formatter.format("upper {lower}"));
         assertEquals("UPPER {l}OWER", formatter.format("upper {l}ower"));
+        assertEquals("1", formatter.format("1"));
+        assertEquals("!", formatter.format("!"));
+
     }
 
     @Test

src/test/java/org/jabref/logic/integrity/HTMLCharacterCheckerTest.java

@@ -9,12 +9,22 @@
 import org.junit.jupiter.api.Test;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 
 public class HTMLCharacterCheckerTest {
 
     private final HTMLCharacterChecker checker = new HTMLCharacterChecker();
     private final BibEntry entry = new BibEntry();
 
+    @Test
+    void fieldNullValueCheck() {
+        Exception exception = assertThrows(
+                NullPointerException.class,
+                () -> entry.setField(StandardField.AUTHOR, null),
+                "field value must not be null"
+        );
+    }
+
     @Test
     void titleAcceptsNonHTMLEncodedCharacters() {
         entry.setField(StandardField.TITLE, "Not a single {HTML} character");

src/test/java/org/jabref/logic/journals/AbbreviationTest.java

@@ -3,6 +3,8 @@
 import org.junit.jupiter.api.Test;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 
 class AbbreviationTest {
 
@@ -101,4 +103,18 @@ void testDefaultAndShortestUniqueAbbreviationsAreSame() {
         Abbreviation abbreviation = new Abbreviation("Long Name", "L N");
         assertEquals(abbreviation.getAbbreviation(), abbreviation.getShortestUniqueAbbreviation());
     }
+
+    @Test
+    void testToString() {
+      Abbreviation abbreviation = new Abbreviation("Long Name", "L N", "LN");
+      assertEquals(abbreviation.toString(), "Abbreviation{name=Long Name, abbreviation=L N, medlineAbbreviation=L N, shortestUniqueAbbreviation=LN}");
+    }
+
+    @Test
+    void testEquals() {
+      Abbreviation abbreviation = new Abbreviation("Long Name", "L N", "LN");
+      Abbreviation otherAbbreviation = new Abbreviation("Long Name", "L N", "LN");
+      assertTrue(abbreviation.equals(otherAbbreviation));
+      assertFalse(abbreviation.equals("String"));
+    }
 }

src/test/java/org/jabref/model/FieldChangeTest.java

@@ -0,0 +1,63 @@
+package org.jabref.model;
+
+import org.jabref.model.entry.BibEntry;
+import org.jabref.model.entry.field.Field;
+import org.jabref.model.entry.field.StandardField;
+
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+class FieldChangeTest {
+
+  private FieldChange Fieldchange;
+
+  @Test
+  void testHashCode() {
+    FieldChange fcNull = new FieldChange(null, null, null, null);
+    assertEquals(923521, fcNull.hashCode());
+  }
+
+  @Test
+  void testEquals() {
+    BibEntry entry = new BibEntry();
+    BibEntry entryOther = new BibEntry();
+    final Field field = StandardField.DOI;
+    final Field fieldOther = StandardField.DOI;
+    entry.setField(StandardField.DOI, "foo");
+    final String oldValue = "foo";
+    final String newValue = "bar";
+    final String oldValueOther = "fooX";
+    final String newValueOther = "barX";
+
+    FieldChange fc = new FieldChange(entry, field, oldValue, newValue);
+    FieldChange fcOther = new FieldChange(entryOther, fieldOther, oldValueOther, newValueOther);
+    FieldChange fcBlankAll = new FieldChange(null, null, null, null);
+    FieldChange fcBlankField = new FieldChange(entry, null, oldValue, newValue);
+    FieldChange fcBlankOldValue = new FieldChange(entry, field, null, newValue);
+    FieldChange fcBlankNewValue = new FieldChange(entry, field, oldValue, null);
+
+    assertFalse(fc.equals("foo"));
+    assertTrue(fc.equals(fc));
+    assertFalse(fcBlankAll.equals(fc));
+    assertFalse(fc.equals(fcOther));
+    assertFalse(fcBlankField.equals(fc));
+    assertFalse(fcBlankOldValue.equals(fc));
+    assertFalse(fcBlankNewValue.equals(fc));
+    assertTrue(fcBlankAll.equals(fcBlankAll));
+  }
+
+  @Test
+  void testToString() {
+    BibEntry entry = new BibEntry();
+    Field field = StandardField.DOI;
+    entry.setCitationKey("CitationKey");
+    final String oldValue = "Old";
+    final String newValue = "New";
+
+    FieldChange fc = new FieldChange(entry, field, oldValue, newValue);
+    assertEquals("FieldChange [entry=CitationKey, field=DOI, oldValue=Old, newValue=New]", fc.toString());
+  }
+}

src/test/java/org/jabref/model/entry/EntryLinkListTest.java

@@ -10,6 +10,7 @@
 import org.junit.jupiter.api.Test;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
 import static org.junit.jupiter.api.Assertions.assertTrue;
 
 public class EntryLinkListTest {
@@ -21,6 +22,7 @@ public class EntryLinkListTest {
     private ParsedEntryLink link;
     private BibEntry source;
     private BibEntry target;
+    private BibEntry entry;
 
     @BeforeEach
     public void before() {
@@ -29,6 +31,7 @@ public void before() {
         link = links.get(0);
         source = create("source");
         target = create("target");
+        entry = create("entry");
     }
 
     private BibEntry create(String citeKey) {
@@ -59,6 +62,12 @@ public void givenFieldValueAndDatabaseWhenParsingThenExpectLink() {
         assertEquals(expected, link);
     }
 
+    @Test
+    public void givenBibEntryWhenParsingThenExpectLink() {
+      ParsedEntryLink expected = new ParsedEntryLink(entry);
+      assertFalse(expected.getLinkedEntry().isEmpty());
+    }
+
     @Test
     public void givenNullFieldValueAndDatabaseWhenParsingThenExpectLinksIsEmpty() {
         links = EntryLinkList.parse(null, database);

src/test/java/org/jabref/model/util/FileHelperTest.java

@@ -1,5 +1,6 @@
 package org.jabref.model.util;
 
+import java.nio.file.Path;
 import java.util.Optional;
 
 import org.junit.jupiter.api.Test;
@@ -18,4 +19,10 @@ public void fileExtensionFromUrl() {
         final String filePath = "https://link.springer.com/content/pdf/10.1007%2Fs40955-018-0121-9.pdf";
         assertEquals(Optional.of("pdf"), FileHelper.getFileExtension(filePath));
     }
+
+    @Test
+    public void testFileNameEmpty() {
+      Path path = Path.of("/");
+      assertEquals(Optional.of(path), FileHelper.find("", path));
+    }
 }