Add truncate as a BibTex key modifier

CHANGELOG.md

@@ -21,6 +21,7 @@ Note that this project **does not** adhere to [Semantic Versioning](http://semve
 - We implemented an option to download fulltext files while importing. [#6381](https://github.com/JabRef/jabref/pull/6381)
 - We added a progress-indicator showing the average progress of background tasks to the toolbar. Clicking it reveals a pop-over with a list of running background tasks. [6443](https://github.com/JabRef/jabref/pull/6443)
 - We fixed the bug when strike the delete key in the text field. [#6421](https://github.com/JabRef/jabref/issues/6421)
+- We added a BibTex key modifier for truncating strings. [#3915](https://github.com/JabRef/jabref/issues/3915)
 - We added support for jumping to target entry when typing letter/digit after sorting a column in maintable [#6146](https://github.com/JabRef/jabref/issues/6146)
 
 ### Changed
@@ -57,6 +58,8 @@ Note that this project **does not** adhere to [Semantic Versioning](http://semve
 - We fixed an issue where JabRef switched to discrete graphics under macOS [#5935](https://github.com/JabRef/jabref/issues/5935)
 - We fixed an issue where the Preferences entry preview will be unexpected modified leads to Value too long exception [#6198](https://github.com/JabRef/jabref/issues/6198)
 - We fixed an issue where custom jstyles for Open/LibreOffice would only be valid if a layout line for the entry type `default` was at the end of the layout section [#6303](https://github.com/JabRef/jabref/issues/6303)
+- We fixed an issue where long directory names created from patterns could create an exception. [#3915](https://github.com/JabRef/jabref/issues/3915)
+
 - We fixed an issue where sort on numeric cases was broken. [#6349](https://github.com/JabRef/jabref/issues/6349)
 - We fixed an issue where an "Not on FX thread" exception occured when saving on linux [#6453](https://github.com/JabRef/jabref/issues/6453)
 - We fixed an issue where the library sort order was lost. [#6091](https://github.com/JabRef/jabref/issues/6091)

src/main/java/org/jabref/logic/formatter/Formatters.java

@@ -5,6 +5,7 @@
 import java.util.List;
 import java.util.Objects;
 import java.util.Optional;
+import java.util.regex.Pattern;
 
 import org.jabref.logic.formatter.bibtexfields.CleanupUrlFormatter;
 import org.jabref.logic.formatter.bibtexfields.ClearFormatter;
@@ -29,10 +30,12 @@
 import org.jabref.logic.formatter.casechanger.TitleCaseFormatter;
 import org.jabref.logic.formatter.casechanger.UpperCaseFormatter;
 import org.jabref.logic.formatter.minifier.MinifyNameListFormatter;
+import org.jabref.logic.formatter.minifier.TruncateFormatter;
 import org.jabref.logic.layout.format.LatexToUnicodeFormatter;
 import org.jabref.model.cleanup.Formatter;
 
 public class Formatters {
+    private static final Pattern TRUNCATE_PATTERN = Pattern.compile("\\Atruncate\\d+\\z");
 
     private Formatters() {
     }
@@ -102,6 +105,9 @@ public static Optional<Formatter> getFormatterForModifier(String modifier) {
         if (modifier.startsWith(RegexFormatter.KEY)) {
             String regex = modifier.substring(RegexFormatter.KEY.length());
             return Optional.of(new RegexFormatter(regex));
+        } else if (TRUNCATE_PATTERN.matcher(modifier).matches()) {
+            int truncateAfter = Integer.parseInt(modifier.substring(8));
+            return Optional.of(new TruncateFormatter(truncateAfter));
         } else {
             return getAll().stream().filter(f -> f.getKey().equals(modifier)).findAny();
         }

src/main/java/org/jabref/logic/formatter/minifier/TruncateFormatter.java

@@ -0,0 +1,51 @@
+package org.jabref.logic.formatter.minifier;
+
+import java.util.Objects;
+
+import org.jabref.logic.l10n.Localization;
+import org.jabref.model.cleanup.Formatter;
+
+public class TruncateFormatter extends Formatter {
+    private final int TRUNCATE_AFTER;
+    private final String KEY;
+
+    /**
+     * The TruncateFormatter truncates a string after the given index and removes trailing whitespaces.
+     *
+     * @param truncateIndex truncate a string after this index.
+     */
+    public TruncateFormatter(final int truncateIndex) {
+        TRUNCATE_AFTER = (truncateIndex >= 0) ? truncateIndex : Integer.MAX_VALUE;
+        KEY = "truncate" + TRUNCATE_AFTER;
+    }
+
+    @Override
+    public String getName() {
+        return Localization.lang("Truncate");
+    }
+
+    @Override
+    public String getKey() {
+        return KEY;
+    }
+
+    /**
+     * Truncates a string after the given index.
+     */
+    @Override
+    public String format(final String input) {
+        Objects.requireNonNull(input);
+        final int index = Math.min(TRUNCATE_AFTER, input.length());
+        return input.substring(0, index).stripTrailing();
+    }
+
+    @Override
+    public String getDescription() {
+        return Localization.lang("Truncates a string after a given index.");
+    }
+
+    @Override
+    public String getExampleInput() {
+        return "Truncate this sentence.";
+    }
+}

src/main/java/org/jabref/logic/util/io/FileUtil.java

@@ -272,22 +272,23 @@ public static String createFileNameFromPattern(BibDatabase database, BibEntry en
     }
 
     /**
-     * Determines filename provided by an entry in a database
+     * Determines directory name provided by an entry in a database
      *
      * @param database        the database, where the entry is located
-     * @param entry           the entry to which the file should be linked to
-     * @param fileNamePattern the filename pattern
-     * @return a suggested fileName
+     * @param entry           the entry to which the directory should be linked to
+     * @param directoryNamePattern the dirname pattern
+     * @return a suggested dirName
      */
-    public static String createDirNameFromPattern(BibDatabase database, BibEntry entry, String fileNamePattern) {
-        String targetName = BracketedPattern.expandBrackets(fileNamePattern, ';', entry, database);
+    public static String createDirNameFromPattern(BibDatabase database, BibEntry entry, String directoryNamePattern) {
+        String targetName = BracketedPattern.expandBrackets(directoryNamePattern, ';', entry, database);
 
         if (targetName.isEmpty()) {
             targetName = entry.getCiteKeyOptional().orElse("default");
         }
 
-        // Removes illegal characters from filename
+        // Removes illegal characters from directory name
         targetName = FileNameCleaner.cleanDirectoryName(targetName);
+
         return targetName;
     }
 

src/main/resources/l10n/JabRef_en.properties

@@ -2241,5 +2241,6 @@ Computer\ software.\ The\ standard\ styles\ will\ treat\ this\ entry\ type\ as\
 A\ data\ set\ or\ a\ similar\ collection\ of\ (mostly)\ raw\ data.=A data set or a similar collection of (mostly) raw data.
 
 Display\ count\ of\ items\ in\ group=Display count of items in group
-
 Remove\ the\ following\ characters\:=Remove the following characters:
+Truncate=Truncate
+Truncates\ a\ string\ after\ a\ given\ index.=Truncates a string after a given index.

src/test/java/org/jabref/logic/util/BracketedPatternTest.java → src/test/java/org/jabref/logic/bibtexkeypattern/BracketedPatternTest.java

@@ -1,6 +1,5 @@
-package org.jabref.logic.util;
+package org.jabref.logic.bibtexkeypattern;
 
-import org.jabref.logic.bibtexkeypattern.BracketedPattern;
 import org.jabref.model.database.BibDatabase;
 import org.jabref.model.entry.BibEntry;
 import org.jabref.model.entry.BibtexString;
@@ -21,7 +20,7 @@ class BracketedPatternTest {
     private BibEntry dbentry;
 
     @BeforeEach
-    void setUp() throws Exception {
+    void setUp() {
         bibentry = new BibEntry();
         bibentry.setField(StandardField.AUTHOR, "O. Kitsune");
         bibentry.setField(StandardField.YEAR, "2017");
@@ -253,4 +252,19 @@ void testEmptyBrackets() {
         assertEquals("2003-Organization Science",
                 BracketedPattern.expandBrackets("[year][]-[journal]", ';', dbentry, database));
     }
+
+    /**
+     * Test the [:truncate] modifier
+     */
+    @Test
+    void expandBracketsChainsTwoTruncateModifiers() {
+        assertEquals("Open",
+                BracketedPattern.expandBrackets("[fulltitle:truncate6:truncate5]", ';', dbentry, database));
+    }
+
+    @Test
+    void expandBracketsDoesNotTruncateWithoutAnArgumentToTruncateModifier() {
+        assertEquals("Open Source Software and the \"Private-Collective\" Innovation Model: Issues for Organization Science",
+                BracketedPattern.expandBrackets("[fulltitle:truncate]", ';', dbentry, database));
+    }
 }

src/test/java/org/jabref/logic/formatter/FormatterTest.java

@@ -6,6 +6,7 @@
 import java.util.stream.Stream;
 
 import org.jabref.logic.formatter.casechanger.ProtectTermsFormatter;
+import org.jabref.logic.formatter.minifier.TruncateFormatter;
 import org.jabref.logic.protectedterms.ProtectedTermsLoader;
 import org.jabref.logic.protectedterms.ProtectedTermsPreferences;
 import org.jabref.model.cleanup.Formatter;
@@ -111,10 +112,12 @@ public static Stream<Formatter> getFormatters() {
                 Formatters.getAll().stream(),
                 // following formatters are not contained in the list of all formatters, because
                 // - the IdentityFormatter is not offered to the user,
-                // - the ProtectTermsFormatter needs more configuration
+                // - the ProtectTermsFormatter needs more configuration,
+                // - the TruncateFormatter needs setup,
                 Stream.of(
                         new IdentityFormatter(),
-                        new ProtectTermsFormatter(protectedTermsLoader)));
+                        new ProtectTermsFormatter(protectedTermsLoader),
+                        new TruncateFormatter(0)));
         // @formatter:on
     }
 }

src/test/java/org/jabref/logic/formatter/minifier/TruncateFormatterTest.java

@@ -0,0 +1,55 @@
+package org.jabref.logic.formatter.minifier;
+
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+/**
+ * Tests in addition to the general tests from {@link org.jabref.logic.formatter.FormatterTest}
+ */
+public class TruncateFormatterTest {
+    private final String TITLE = "A Title";
+
+    @Test
+    void formatWorksWith0Index() {
+        TruncateFormatter formatter = new TruncateFormatter(0);
+        assertEquals("", formatter.format(TITLE));
+    }
+
+    @Test
+    void formatRemovesTrailingWhitespace() {
+        TruncateFormatter formatter = new TruncateFormatter(2);
+        assertEquals("A", formatter.format(TITLE));
+    }
+
+    @Test
+    void formatKeepsInternalWhitespace() {
+        TruncateFormatter formatter = new TruncateFormatter(3);
+        assertEquals("A T", formatter.format(TITLE));
+    }
+
+    @Test
+    void formatWorksWith9999Length() {
+        TruncateFormatter formatter = new TruncateFormatter(9999);
+        assertEquals(TITLE, formatter.format(TITLE));
+    }
+
+    @Test
+    void formatIgnoresNegativeIndex() {
+        TruncateFormatter formatter = new TruncateFormatter(-1);
+        assertEquals(TITLE, formatter.format(TITLE));
+    }
+
+    @Test
+    void formatWorksWithEmptyString() {
+        TruncateFormatter formatter = new TruncateFormatter(9999);
+        assertEquals("", formatter.format(""));
+    }
+
+    @Test
+    void formatThrowsExceptionNullString() {
+        TruncateFormatter formatter = new TruncateFormatter(9999);
+        assertThrows(NullPointerException.class, () -> formatter.format(null));
+    }
+}