considering multiple spaces as separate user block by replacing it with " and " (#12757)

* considering multiple spaces as separate user block by replacing it with " and "

* considering multiple spaces as separate user block by replacing it with " and "

* considering multiple spaces as separate user block by replacing it with " and "

* considering multiple spaces as separate user block by replacing it with " and "

* considering multiple spaces as separate user block by replacing it with " and "

* Revert "considering multiple spaces as separate user block by replacing it with " and ""

This reverts commit ca6e337

* considering multiple spaces as separate user block by replacing it with " and "

* considering multiple spaces as separate user block by replacing it with " and "

* considering multiple spaces as separate user block by replacing it with " and "

* Update CHANGELOG.md

Co-authored-by: Oliver Kopp <kopp.dev@gmail.com>

* considering multiple spaces as separate user block by replacing it with " and "

---------

Co-authored-by: Oliver Kopp <kopp.dev@gmail.com>

Author: rishivardhanmm

CHANGELOG.md

@@ -22,6 +22,7 @@ Note that this project **does not** adhere to [Semantic Versioning](https://semv
 - We added an integrity check if a URL appears in a title. [#12354](https://github.com/JabRef/jabref/issues/12354)
 - We added a feature for enabling drag-and-drop of files into groups  [#12540](https://github.com/JabRef/jabref/issues/12540)
 - We added support for reordering keywords via drag and drop, automatic alphabetical ordering, and improved pasting and editing functionalities in the keyword editor. [#10984](https://github.com/JabRef/jabref/issues/10984)
+- We added a new functionality where author names having multiple spaces in-between will be considered as separate user block as it does for " and ". [#12701](https://github.com/JabRef/jabref/issues/12701)
 
 ### Changed
 

src/main/java/org/jabref/logic/importer/AuthorListParser.java

@@ -39,6 +39,10 @@ public class AuthorListParser {
 
     private static final Pattern STARTS_WITH_CAPITAL_LETTER_DOT_OR_DASH = Pattern.compile("^[A-Z](\\.[ -]| ?-)");
 
+    private static final Pattern MULTIPLE_SPACE_PATTERN = Pattern.compile("\\s{2,}");
+
+    private static final Pattern NEW_LINE_PATTERN = Pattern.compile("\\s*\\n\\s*");
+
     /**
      * the raw bibtex author/editor field
      */
@@ -100,6 +104,10 @@ private record SimpleNormalFormResult(String authors, boolean andOthersPresent)
 
     private static SimpleNormalFormResult getSimpleNormalForm(String listOfNames) {
         listOfNames = listOfNames.replace(" -", "-").trim();
+        if (!listOfNames.contains(",") && (MULTIPLE_SPACE_PATTERN.matcher(listOfNames).find() || listOfNames.contains("\n"))) {
+            listOfNames = NEW_LINE_PATTERN.matcher(listOfNames).replaceAll(" and ");
+            listOfNames = MULTIPLE_SPACE_PATTERN.matcher(listOfNames).replaceAll(" and ");
+        }
 
         // Handling of "and others"
         // Remove it from the list; it will be added at the very end of this method as special Author.OTHERS

src/test/java/org/jabref/logic/importer/AuthorListParserTest.java

@@ -79,7 +79,37 @@ private static Stream<Arguments> parseMultipleCorrectly() {
                                 new Author("Thomas", "T.", null, "Lai", null)
                         ),
                         "U, Vivian and Lai, Thomas"
-                )
+                ),
+                Arguments.of(
+                        AuthorList.of(
+                                new Author("I.", "I.", null, "Podadera", null),
+                                new Author("J. M.", "J. M.", null, "Carmona", null),
+                                new Author("A.", "A.", null, "Ibarra", null),
+                                new Author("J.", "J.", null, "Molla", null)
+                        ),
+                        "I. Podadera      J. M. Carmona     A. Ibarra     J. Molla"),
+                Arguments.of(
+                        AuthorList.of(
+                                new Author("Alexander", "A.", null, "Artemenko", null),
+                                new Author("I.", "I.", null, "Podadera", null),
+                                new Author("J. M.", "J. M.", null, "Carmona", null)
+                        ),
+                        """
+                        Alexander Artemenko
+                        I. Podadera
+                        J. M. Carmona
+                        """),
+                Arguments.of(
+                        AuthorList.of(
+                                new Author("First1", "F.", null, "Last1", null),
+                                new Author("First2", "F.", null, "Last2", null),
+                                new Author("First3", "F.", null, "Last3", null)
+                        ),
+                        """
+                        First1 Last1
+                            First2 Last2
+                            First3 Last3
+                        """)
         );
     }