QSettings: Don't chop off trailing tabs that were actually part of a value.

This was done wrong when using the ini format.

Task-number:  QTBUG-22461
Change-Id: Ib9390460bce6138659cceac7e3cd25339ba5e9bb
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@digia.com>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

src/corelib/io/qsettings.cpp

@@ -774,11 +774,11 @@ void QSettingsPrivate::iniEscapedString(const QString &str, QByteArray &result,
     }
 }
 
-inline static void iniChopTrailingSpaces(QString &str)
+inline static void iniChopTrailingSpaces(QString &str, int limit)
 {
     int n = str.size() - 1;
     QChar ch;
-    while (n >= 0 && ((ch = str.at(n)) == QLatin1Char(' ') || ch == QLatin1Char('\t')))
+    while (n >= limit && ((ch = str.at(n)) == QLatin1Char(' ') || ch == QLatin1Char('\t')))
         str.truncate(n--);
 }
 
@@ -836,6 +836,7 @@ StSkipSpaces:
     // fallthrough
 
 StNormal:
+    int chopLimit = stringResult.length();
     while (i < to) {
         switch (str.at(i)) {
         case '\\':
@@ -873,6 +874,7 @@ StNormal:
             } else {
                 // the character is skipped
             }
+            chopLimit = stringResult.length();
             break;
         case '"':
             ++i;
@@ -884,7 +886,7 @@ StNormal:
         case ',':
             if (!inQuotedString) {
                 if (!currentValueIsQuoted)
-                    iniChopTrailingSpaces(stringResult);
+                    iniChopTrailingSpaces(stringResult, chopLimit);
                 if (!isStringList) {
                     isStringList = true;
                     stringListResult.clear();
@@ -924,6 +926,8 @@ StNormal:
         }
         }
     }
+    if (!currentValueIsQuoted)
+        iniChopTrailingSpaces(stringResult, chopLimit);
     goto end;
 
 StHexEscape:
@@ -963,8 +967,6 @@ StOctEscape:
     }
 
 end:
-    if (!currentValueIsQuoted)
-        iniChopTrailingSpaces(stringResult);
     if (isStringList)
         stringListResult.append(stringResult);
     return isStringList;

tests/auto/corelib/io/qsettings/tst_qsettings.cpp

@@ -128,6 +128,7 @@ private slots:
     void testEmptyData();
     void testResourceFiles();
     void testRegistryShortRootNames();
+    void trailingWhitespace();
 #ifdef Q_OS_MAC
     void fileName();
 #endif
@@ -2030,6 +2031,23 @@ void tst_QSettings::testRegistryShortRootNames()
 #endif
 }
 
+void tst_QSettings::trailingWhitespace()
+{
+    {
+        QSettings s("tst_QSettings_trailingWhitespace");
+        s.setValue("trailingSpace", "x  ");
+        s.setValue("trailingTab", "x\t");
+        s.setValue("trailingNewline", "x\n");
+    }
+    {
+        QSettings s("tst_QSettings_trailingWhitespace");
+        QCOMPARE(s.value("trailingSpace").toString(), QLatin1String("x  "));
+        QCOMPARE(s.value("trailingTab").toString(), QLatin1String("x\t"));
+        QCOMPARE(s.value("trailingNewline").toString(), QLatin1String("x\n"));
+        s.clear();
+    }
+}
+
 void tst_QSettings::fromFile_data()
 {
     populateWithFormats();