Fix reading of XDG style semicolon separated lists with escaped ';'

Previously the warning "Invalid escape sequence "\;"." would appear and
"\;" was replaced with just the backslash as is done for all
unrecognized escape sequences. Keep both characters so that
readXdgListEntry() works with values containing semicolons

REVIEW: 119074

autotests/kconfigtest.cpp

@@ -1672,6 +1672,33 @@ void KConfigTest::testNewlines()
 
 }
 
+void KConfigTest::testXdgListEntry()
+{
+    QTemporaryFile file;
+    QVERIFY(file.open());
+    QTextStream out(&file);
+    out <<  "[General]" << endl
+        << "Key1=" << endl // empty list
+        // emtpty entries
+        << "Key2=;" << endl
+        << "Key3=;;" << endl
+        << "Key4=;;;" << endl
+        << "Key5=\\;" << endl
+        << "Key6=1;2\\;3;;" << endl;
+    out.flush();
+    file.close();
+    KConfig anonConfig(file.fileName(), KConfig::SimpleConfig);
+    KConfigGroup grp = anonConfig.group("General");
+    QStringList invalidList; // use this as a default when an empty list is expected
+    invalidList << "Error! Default value read!";
+    QCOMPARE(grp.readXdgListEntry("Key1", invalidList), QStringList());
+    QCOMPARE(grp.readXdgListEntry("Key2", invalidList), QStringList() << QString());
+    QCOMPARE(grp.readXdgListEntry("Key3", invalidList), QStringList() << QString() << QString());
+    QCOMPARE(grp.readXdgListEntry("Key4", invalidList), QStringList()<< QString() << QString() << QString());
+    QCOMPARE(grp.readXdgListEntry("Key5", invalidList), QStringList() << ";");
+    QCOMPARE(grp.readXdgListEntry("Key6", invalidList), QStringList() << "1" << "2;3" << QString());
+}
+
 #include <QThreadPool>
 #include <qtconcurrentrun.h>
 

autotests/kconfigtest.h

@@ -76,6 +76,7 @@ private Q_SLOTS:
     void testDirtyAfterRevert();
     void testKdeGlobals();
     void testNewlines();
+    void testXdgListEntry();
 
     void testThreads();
 

autotests/kdesktopfiletest.cpp

@@ -142,21 +142,35 @@ void KDesktopFileTest::testActionGroup()
     QTextStream ts(&file);
     ts <<
        "[Desktop Entry]\n"
-       "Actions=encrypt;\n"
+       // make sure escaping of ';' using "\;" works
+       "Actions=encrypt;semi\\;colon;decrypt;\n"
        "[Desktop Action encrypt]\n"
        "Name=Encrypt file\n"
+       "[Desktop Action decrypt]\n"
+       "Name=Decrypt file\n"
+       // no escaping needed in group header
+       "[Desktop Action semi;colon]\n"
+       "Name=With semicolon\n"
        "\n";
     file.close();
     QVERIFY(QFile::exists(fileName));
     KDesktopFile df(fileName);
     QCOMPARE(df.readType(), QString());
     QCOMPARE(df.fileName(), fileName);
-    QCOMPARE(df.readActions(), QStringList() << "encrypt");
+    QCOMPARE(df.readActions(), QStringList() << "encrypt" << "semi;colon" << "decrypt");
     QCOMPARE(df.hasActionGroup("encrypt"), true);
+    QCOMPARE(df.hasActionGroup("semi;colon"), true);
+    QCOMPARE(df.hasActionGroup("decrypt"), true);
     QCOMPARE(df.hasActionGroup("doesnotexist"), false);
     KConfigGroup cg = df.actionGroup("encrypt");
     QVERIFY(cg.hasKey("Name"));
     QCOMPARE(cg.readEntry("Name"), QString("Encrypt file"));
+    cg = df.actionGroup("decrypt");
+    QVERIFY(cg.hasKey("Name"));
+    QCOMPARE(cg.readEntry("Name"), QString("Decrypt file"));
+    cg = df.actionGroup("semi;colon");
+    QVERIFY(cg.hasKey("Name"));
+    QCOMPARE(cg.readEntry("Name"), QString("With semicolon"));
 }
 
 void KDesktopFileTest::testIsAuthorizedDesktopFile()

src/core/kconfigini.cpp

@@ -792,6 +792,12 @@ void KConfigIniBackend::printableToString(BufferFragment *aString, const QFile &
             case '\\':
                 *r = '\\';
                 break;
+            case ';':
+                // not really an escape sequence, but allowed in .desktop files, don't strip '\;' from the string
+                *r = '\\';
+                r++;
+                *r = ';';
+                break;
             case 'x':
                 if (i + 2 < l) {
                     *r = charFromHex(str + i + 1, file, line);