[search] Fix corner cases when using quotes in filenames

The `filename` term in a search query is enclosed into quotes.
As the user can have additional quotes in the search term, there were several
corner cases where the parsing would fail to correctly split the terms

New test cases have been added to cover this possibility
Previous tests still passes to avoid regressions

BEFORE:
```
(filename/quoted) Compared values are not the same
Actual   (query.text()): "xyz\"\""
Expected (expectedText): "\"abc xyz\""

(filename/mixed) Compared values are not the same
Actual   (query.text()): "xyz\" tuv\""
Expected (expectedText): "\"abc xyz\" tuv"

(content+filename/quoted) Compared values are not the same
Actual   (query.text()): "abc xyz xyz\"\""
Expected (expectedText): "abc xyz filename:\"\"abc xyz\"\""
```

1 files changed, 5 insertions, 1 deletions

diff --git a/src/search/dolphinquery.cpp b/src/search/dolphinquery.cpp
index 0581a02ec..663ed9909 100644
--- a/src/search/dolphinquery.cpp
+++ b/src/search/dolphinquery.cpp
@@ -59,7 +59,11 @@ namespace {
 
     QStringList splitOutsideQuotes(const QString& text)
     {
-        const QRegularExpression subTermsRegExp("(\\S*?\"[^\"]*?\"|(?<=\\s|^)\\S+(?=\\s|$))");
+        // Match groups on 3 possible conditions:
+        //   - Groups with two leading quotes must close both on them (filename:""abc xyz" tuv")
+        //   - Groups enclosed in quotes
+        //   - Words separated by spaces
+        const QRegularExpression subTermsRegExp("(\\S*?\"\"[^\"]+\"[^\"]+\"+|\\S*?\"[^\"]+\"+|(?<=\\s|^)\\S+(?=\\s|$))");
         auto subTermsMatchIterator = subTermsRegExp.globalMatch(text);
 
         QStringList textParts;