Fix not escaping special characters in search pattern (#5938)

* Fix not escaping special characters in search pattern

fixes #5892

* add method to get search pattern for searched words with escaped
 javascript regexp special characters (for search without regular
 expressions)

* in preview viewer use search pattern with escaped javascript regexp
 special characters

* Refactoring and performance improvement

* use enum to specify special characters escape mode

* use compiled regex pattern instead of string

* Refactoring: braces in if..else

* Refactoring, minor changes: names, comments

* Add tests of escaping special characters in search patterns

src/main/java/org/jabref/gui/preview/PreviewViewer.java

@@ -85,7 +85,7 @@ public class PreviewViewer extends ScrollPane implements InvalidationListener {
     private boolean registered;
 
     private ChangeListener<Optional<SearchQuery>> listener = (queryObservable, queryOldValue, queryNewValue) -> {
-        searchHighlightPattern = queryNewValue.flatMap(SearchQuery::getPatternForWords);
+        searchHighlightPattern = queryNewValue.flatMap(SearchQuery::getJavaScriptPatternForWords);
         highlightSearchPattern();
     };
 
@@ -131,7 +131,7 @@ public void setTheme(String theme) {
 
     private void highlightSearchPattern() {
         if (searchHighlightPattern.isPresent()) {
-            String pattern = searchHighlightPattern.get().pattern().replace("\\Q", "").replace("\\E", "");
+            String pattern = searchHighlightPattern.get().pattern();
 
             previewView.getEngine().executeScript(
                     "var markInstance = new Mark(document.getElementById(\"content\"));" +

src/main/java/org/jabref/logic/search/SearchQuery.java

@@ -18,6 +18,25 @@
 
 public class SearchQuery implements SearchMatcher {
 
+    /**
+     * Regex pattern for escaping special characters in javascript regular expressions
+     */
+    public static final Pattern JAVASCRIPT_ESCAPED_CHARS_PATTERN = Pattern.compile("[\\.\\*\\+\\?\\^\\$\\{\\}\\(\\)\\|\\[\\]\\\\/]");
+
+    /**
+     * The mode of escaping special characters in regular expressions
+     */
+    private enum EscapeMode {
+        /**
+         * using \Q and \E marks
+         */
+        JAVA,
+        /**
+         * escaping all javascript regex special characters separately
+         */
+        JAVASCRIPT
+    }
+
     private final String query;
     private final boolean caseSensitive;
     private final boolean regularExpression;
@@ -124,6 +143,18 @@ public List<String> getSearchWords() {
 
     // Returns a regular expression pattern in the form (w1)|(w2)| ... wi are escaped if no regular expression search is enabled
     public Optional<Pattern> getPatternForWords() {
+        return joinWordsToPattern(EscapeMode.JAVA);
+    }
+
+    // Returns a regular expression pattern in the form (w1)|(w2)| ... wi are escaped for javascript if no regular expression search is enabled
+    public Optional<Pattern> getJavaScriptPatternForWords() {
+        return joinWordsToPattern(EscapeMode.JAVASCRIPT);
+    }
+
+    /** Returns a regular expression pattern in the form (w1)|(w2)| ... wi are escaped if no regular expression search is enabled
+     * @param escapeMode the mode of escaping special characters in wi
+     */
+    private Optional<Pattern> joinWordsToPattern(EscapeMode escapeMode) {
         List<String> words = getSearchWords();
 
         if ((words == null) || words.isEmpty() || words.get(0).isEmpty()) {
@@ -133,7 +164,20 @@ public Optional<Pattern> getPatternForWords() {
         // compile the words to a regular expression in the form (w1)|(w2)|(w3)
         StringJoiner joiner = new StringJoiner(")|(", "(", ")");
         for (String word : words) {
-            joiner.add(regularExpression ? word : Pattern.quote(word));
+            if (regularExpression) {
+                joiner.add(word);
+            } else {
+                switch (escapeMode) {
+                    case JAVA:
+                        joiner.add(Pattern.quote(word));
+                        break;
+                    case JAVASCRIPT:
+                        joiner.add(JAVASCRIPT_ESCAPED_CHARS_PATTERN.matcher(word).replaceAll("\\\\$0"));
+                        break;
+                    default:
+                        throw new IllegalArgumentException("Unknown special characters escape mode: " + escapeMode);
+                }
+            }
         }
         String searchPattern = joiner.toString();
 

src/test/java/org/jabref/logic/search/SearchQueryTest.java

@@ -203,4 +203,38 @@ public void testGetPattern() {
         //We can't directly compare the pattern objects
         assertEquals(Optional.of(pattern.toString()), result.getPatternForWords().map(Pattern::toString));
     }
+
+    @Test
+    public void testGetRegexpPattern() {
+        String queryText = "[a-c]\\d* \\d*";
+        SearchQuery regexQuery = new SearchQuery(queryText, false, true);
+        Pattern pattern = Pattern.compile("([a-c]\\d* \\d*)");
+        assertEquals(Optional.of(pattern.toString()), regexQuery.getPatternForWords().map(Pattern::toString));
+    }
+
+    @Test
+    public void testGetRegexpJavascriptPattern() {
+        String queryText = "[a-c]\\d* \\d*";
+        SearchQuery regexQuery = new SearchQuery(queryText, false, true);
+        Pattern pattern = Pattern.compile("([a-c]\\d* \\d*)");
+        assertEquals(Optional.of(pattern.toString()), regexQuery.getJavaScriptPatternForWords().map(Pattern::toString));
+    }
+
+    @Test
+    public void testEscapingInPattern() {
+        //first word contain all java special regex characters
+        String queryText = "<([{\\\\^-=$!|]})?*+.> word1 word2.";
+        SearchQuery textQueryWithSpecialChars = new SearchQuery(queryText, false, false);
+        String pattern = "(\\Q<([{\\^-=$!|]})?*+.>\\E)|(\\Qword1\\E)|(\\Qword2.\\E)";
+        assertEquals(Optional.of(pattern), textQueryWithSpecialChars.getPatternForWords().map(Pattern::toString));
+    }
+
+    @Test
+    public void testEscapingInJavascriptPattern() {
+        //first word contain all javascript special regex characters that should be escaped individually in text based search
+        String queryText = "([{\\\\^$|]})?*+./ word1 word2.";
+        SearchQuery textQueryWithSpecialChars = new SearchQuery(queryText, false, false);
+        String pattern = "(\\(\\[\\{\\\\\\^\\$\\|\\]\\}\\)\\?\\*\\+\\.\\/)|(word1)|(word2\\.)";
+        assertEquals(Optional.of(pattern), textQueryWithSpecialChars.getJavaScriptPatternForWords().map(Pattern::toString));
+    }
 }