Introduce QRegularExpression::NoMatch match type

This match type doesn't do any match at all; it's only necessary to
properly introduce default constructors for QRegularExpressionMatch
and QRegularExpressionMatchIterator (since they return the match type
that created them).

Change-Id: Ibfe92459c7fdd23129cf3afe073cd443c461ddeb
Reviewed-by: Lars Knoll <lars.knoll@digia.com>

src/corelib/tools/qregularexpression.cpp

@@ -1,6 +1,7 @@
 /****************************************************************************
 **
 ** Copyright (C) 2012 Giuseppe D'Angelo <dangelog@gmail.com>.
+** Copyright (C) 2012 Klarälvdalens Datakonsult AB, a KDAB Group company, info@kdab.com, author Giuseppe D'Angelo <giuseppe.dangelo@kdab.com>
 ** Copyright (C) 2012 Digia Plc and/or its subsidiary(-ies).
 ** Contact: http://www.qt-project.org/legal
 **
@@ -725,6 +726,13 @@ QT_BEGIN_NAMESPACE
         that (in this text) there are other characters beyond the end of the
         subject string. This can lead to surprising results; see the discussion
         in the \l{partial matching} section for more details.
+
+    \value NoMatch
+        No matching is done. This value is returned as the match type by a
+        default constructed QRegularExpressionMatch or
+        QRegularExpressionMatchIterator. Using this match type is not very
+        useful for the user, as no matching ever happens. This enum value
+        has been introduced in Qt 5.1.
 */
 
 /*!
@@ -1200,6 +1208,15 @@ QRegularExpressionMatchPrivate *QRegularExpressionPrivate::doMatch(const QString
         return new QRegularExpressionMatchPrivate(re, subject, matchType, matchOptions, 0);
     }
 
+    // skip optimizing and doing the actual matching if NoMatch type was requested
+    if (matchType == QRegularExpression::NoMatch) {
+        QRegularExpressionMatchPrivate *priv = new QRegularExpressionMatchPrivate(re, subject,
+                                                                                  matchType, matchOptions,
+                                                                                  0);
+        priv->isValid = true;
+        return priv;
+    }
+
     QRegularExpressionMatchPrivate *priv = new QRegularExpressionMatchPrivate(re, subject,
                                                                               matchType, matchOptions,
                                                                               capturingCount);

src/corelib/tools/qregularexpression.h

@@ -1,6 +1,7 @@
 /****************************************************************************
 **
 ** Copyright (C) 2012 Giuseppe D'Angelo <dangelog@gmail.com>.
+** Copyright (C) 2012 Klarälvdalens Datakonsult AB, a KDAB Group company, info@kdab.com, author Giuseppe D'Angelo <giuseppe.dangelo@kdab.com>
 ** Contact: http://www.qt-project.org/legal
 **
 ** This file is part of the QtCore module of the Qt Toolkit.
@@ -99,7 +100,8 @@ public:
     enum MatchType {
         NormalMatch = 0,
         PartialPreferCompleteMatch,
-        PartialPreferFirstMatch
+        PartialPreferFirstMatch,
+        NoMatch
     };
 
     enum MatchOption {

tests/auto/corelib/tools/qregularexpression/tst_qregularexpression.cpp

@@ -127,8 +127,6 @@ bool operator!=(const Match &m, const QRegularExpressionMatch &rem)
 bool operator==(const QRegularExpressionMatchIterator &iterator, const QList<Match> &expectedMatchList)
 {
     QRegularExpressionMatchIterator i = iterator;
-    if (i.isValid() != (!expectedMatchList.isEmpty()))
-        return false;
 
     foreach (const Match &expectedMatch, expectedMatchList)
     {
@@ -694,14 +692,30 @@ void tst_QRegularExpression::normalMatch()
     QFETCH(QRegularExpression::MatchOptions, matchOptions);
     QFETCH(Match, match);
 
-    QRegularExpressionMatch m = regexp.match(subject, offset, QRegularExpression::NormalMatch, matchOptions);
+    {
-    consistencyCheck(m);
+        QRegularExpressionMatch m = regexp.match(subject, offset, QRegularExpression::NormalMatch, matchOptions);
-    QVERIFY(m == match);
+        consistencyCheck(m);
-    QCOMPARE(m.regularExpression(), regexp);
+        QVERIFY(m == match);
-    QCOMPARE(m.matchType(), QRegularExpression::NormalMatch);
+        QCOMPARE(m.regularExpression(), regexp);
-    QCOMPARE(m.matchOptions(), matchOptions);
+        QCOMPARE(m.matchType(), QRegularExpression::NormalMatch);
-}
+        QCOMPARE(m.matchOptions(), matchOptions);
+    }
+    {
+        // ignore the expected results provided by the match object --
+        // we'll never get any result when testing the NoMatch type.
+        // Just check the validity of the match here.
+        Match realMatch;
+        realMatch.clear();
+        realMatch.isValid = match.isValid;
 
+        QRegularExpressionMatch m = regexp.match(subject, offset, QRegularExpression::NoMatch, matchOptions);
+        consistencyCheck(m);
+        QVERIFY(m == realMatch);
+        QCOMPARE(m.regularExpression(), regexp);
+        QCOMPARE(m.matchType(), QRegularExpression::NoMatch);
+        QCOMPARE(m.matchOptions(), matchOptions);
+    }
+}
 
 void tst_QRegularExpression::partialMatch_data()
 {
@@ -956,12 +970,29 @@ void tst_QRegularExpression::partialMatch()
     QFETCH(QRegularExpression::MatchOptions, matchOptions);
     QFETCH(Match, match);
 
-    QRegularExpressionMatch m = regexp.match(subject, offset, matchType, matchOptions);
+    {
-    consistencyCheck(m);
+        QRegularExpressionMatch m = regexp.match(subject, offset, matchType, matchOptions);
-    QVERIFY(m == match);
+        consistencyCheck(m);
-    QCOMPARE(m.regularExpression(), regexp);
+        QVERIFY(m == match);
-    QCOMPARE(m.matchType(), matchType);
+        QCOMPARE(m.regularExpression(), regexp);
-    QCOMPARE(m.matchOptions(), matchOptions);
+        QCOMPARE(m.matchType(), matchType);
+        QCOMPARE(m.matchOptions(), matchOptions);
+    }
+    {
+        // ignore the expected results provided by the match object --
+        // we'll never get any result when testing the NoMatch type.
+        // Just check the validity of the match here.
+        Match realMatch;
+        realMatch.clear();
+        realMatch.isValid = match.isValid;
+
+        QRegularExpressionMatch m = regexp.match(subject, offset, QRegularExpression::NoMatch, matchOptions);
+        consistencyCheck(m);
+        QVERIFY(m == realMatch);
+        QCOMPARE(m.regularExpression(), regexp);
+        QCOMPARE(m.matchType(), QRegularExpression::NoMatch);
+        QCOMPARE(m.matchOptions(), matchOptions);
+    }
 }
 
 void tst_QRegularExpression::globalMatch_data()
@@ -1230,13 +1261,28 @@ void tst_QRegularExpression::globalMatch()
     QFETCH(QRegularExpression::MatchType, matchType);
     QFETCH(QRegularExpression::MatchOptions, matchOptions);
     QFETCH(QList<Match>, matchList);
+    {
+        QRegularExpressionMatchIterator iterator = regexp.globalMatch(subject, offset, matchType, matchOptions);
+        consistencyCheck(iterator);
+        QVERIFY(iterator == matchList);
+        QCOMPARE(iterator.regularExpression(), regexp);
+        QCOMPARE(iterator.matchType(), matchType);
+        QCOMPARE(iterator.matchOptions(), matchOptions);
+    }
+    {
+        // ignore the expected results provided by the match object --
+        // we'll never get any result when testing the NoMatch type.
+        // Just check the validity of the match here.
+        QList<Match> realMatchList;
+
+        QRegularExpressionMatchIterator iterator = regexp.globalMatch(subject, offset, QRegularExpression::NoMatch, matchOptions);
+        consistencyCheck(iterator);
+        QVERIFY(iterator == realMatchList);
+        QCOMPARE(iterator.regularExpression(), regexp);
+        QCOMPARE(iterator.matchType(), QRegularExpression::NoMatch);
+        QCOMPARE(iterator.matchOptions(), matchOptions);
+    }
 
-    QRegularExpressionMatchIterator iterator = regexp.globalMatch(subject, offset, matchType, matchOptions);
-    consistencyCheck(iterator);
-    QVERIFY(iterator == matchList);
-    QCOMPARE(iterator.regularExpression(), regexp);
-    QCOMPARE(iterator.matchType(), matchType);
-    QCOMPARE(iterator.matchOptions(), matchOptions);
 }
 
 void tst_QRegularExpression::serialize_data()