Fix conversion of "'n" and "\'{n}" from LaTeX to Unicode (#2464)

CHANGELOG.md

@@ -18,7 +18,7 @@ We refer to [GitHub issues](https://github.com/JabRef/jabref/issues) by using `#
 - Backslashes in content selectors are now correctly escaped. Fixes [#2426](https://github.com/JabRef/jabref/issues/2426).
 - Non-ISO timestamp settings prevented the opening of the entry editor (see [#2447](https://github.com/JabRef/jabref/issues/2447))
 - When pressing <kbd>Ctrl</kbd> + <kbd>F</kbd> and the searchbar is already focused the text will be selected.
-- LaTeX symbols are now displayed as Unicode for the author column in the main table. Fixes [#2458](https://github.com/JabRef/jabref/issues/2458).
+- LaTeX symbols are now displayed as Unicode for the author column in the main table. "'n" and "\'{n}" are parsed correctly. Fixes [#2458](https://github.com/JabRef/jabref/issues/2458).
 
 ### Removed
 

src/main/java/net/sf/jabref/model/strings/LatexToUnicode.java

@@ -62,6 +62,12 @@ public String format(String inField) {
                     || StringUtil.SPECIAL_COMMAND_CHARS.contains(String.valueOf(c))) {
                 escaped = false;
 
+                // a single ' can also be a command
+                if('\'' == c){
+                    incommand = true;
+                    currentCommand = new StringBuilder();
+                }
+
                 if (!incommand) {
                     sb.append(c);
                 } else {
@@ -83,7 +89,7 @@ public String format(String inField) {
                         } else {
                             commandBody = field.substring(i, i + 1);
                         }
-                        String result = CHARS.get(command + commandBody);
+                        String result = fixCollidingCommand(CHARS.get(command + commandBody), c);
 
                         if (result == null) {
                             // Use combining accents if argument is single character or empty
@@ -206,4 +212,13 @@ public String format(String inField) {
         return result;
 
     }
+
+    private String fixCollidingCommand(String currentChar, Character bracket) {
+        // when stripping Latex, there is a collision between unicode characters 324 and 329. Hence, this needs to be checked
+        if (!("ʼn".equals(currentChar) && '{' == bracket)) {
+            return currentChar;
+        } else {
+            return "ń";
+        }
+    }
 }

src/test/java/net/sf/jabref/logic/layout/format/LatexToUnicodeFormatterTest.java

@@ -92,4 +92,10 @@ public void unknownCommandWithEmptyArgumentIsKept() {
     public void testTildeN () {
         assertEquals("Montaña", formatter.format("Monta\\~{n}a"));
     }
+
+    @Test
+    public void testApostrophN () {
+        assertEquals("Maliński", formatter.format("Mali\\'{n}ski"));
+        assertEquals("Maliʼnski", formatter.format("Mali'nski"));
+    }
 }