QString::contains overload that returns the match results

This convenience overload allows one to write

    QRegularExpression re1, re2, ...;
    QRegularExpressionMatch match;
    QString subject;

    if (subject.contains(re1, &match)) {
        // ...
    } else if (subject.contains(re2, &match)) {
        // ...
    } // ..

One can then inspect the results of a successful match in each block
(as well as extracting the captured substrings, etc.).

Change-Id: I0fb8be8b577656e8db994198f8105c26c4fe67b0
Reviewed-by: Lars Knoll <lars.knoll@digia.com>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

3 files changed, 78 insertions, 0 deletions

diff --git a/src/corelib/tools/qstring.cpp b/src/corelib/tools/qstring.cpp
index 10ef6b34dd..a3036a3f24 100644
--- a/src/corelib/tools/qstring.cpp
+++ b/src/corelib/tools/qstring.cpp
@@ -3340,6 +3340,33 @@ bool QString::contains(const QRegularExpression &re) const
 }
 
 /*!
+    \overload contains()
+    \since 5.1
+
+    Returns true if the regular expression \a re matches somewhere in this
+    string; otherwise returns false.
+
+    If the match is successful and \a match is not a null pointer, it also
+    writes the results of the match into the QRegularExpressionMatch object
+    pointed by \a match.
+
+    \sa QRegularExpression::match()
+*/
+
+bool QString::contains(const QRegularExpression &re, QRegularExpressionMatch *match) const
+{
+    if (!re.isValid()) {
+        qWarning("QString::contains: invalid QRegularExpresssion object");
+        return false;
+    }
+    QRegularExpressionMatch m = re.match(*this);
+    bool hasMatch = m.hasMatch();
+    if (hasMatch && match)
+        *match = m;
+    return hasMatch;
+}
+
+/*!
     \overload count()
     \since 5.0
 
diff --git a/src/corelib/tools/qstring.h b/src/corelib/tools/qstring.h
index 574285fa1e..b7a08928b3 100644
--- a/src/corelib/tools/qstring.h
+++ b/src/corelib/tools/qstring.h
@@ -72,6 +72,7 @@ QT_BEGIN_NAMESPACE
 class QCharRef;
 class QRegExp;
 class QRegularExpression;
+class QRegularExpressionMatch;
 class QString;
 class QStringList;
 class QTextCodec;
@@ -339,6 +340,7 @@ public:
     int indexOf(const QRegularExpression &re, int from = 0) const;
     int lastIndexOf(const QRegularExpression &re, int from = -1) const;
     bool contains(const QRegularExpression &re) const;
+    bool contains(const QRegularExpression &re, QRegularExpressionMatch *match) const;
     int count(const QRegularExpression &re) const;
 #endif
 
diff --git a/tests/auto/corelib/tools/qstring/tst_qstring.cpp b/tests/auto/corelib/tools/qstring/tst_qstring.cpp
index 740581ceec..24dfac8c01 100644
--- a/tests/auto/corelib/tools/qstring/tst_qstring.cpp
+++ b/tests/auto/corelib/tools/qstring/tst_qstring.cpp
@@ -1425,6 +1425,55 @@ void tst_QString::contains()
     QVERIFY(a.contains(QRegularExpression("[FG][HI]")));
     QVERIFY(a.contains(QRegularExpression("[G][HE]")));
 
+    {
+        QRegularExpressionMatch match;
+        QVERIFY(!match.hasMatch());
+
+        QVERIFY(a.contains(QRegularExpression("[FG][HI]"), &match));
+        QVERIFY(match.hasMatch());
+        QCOMPARE(match.capturedStart(), 6);
+        QCOMPARE(match.capturedEnd(), 8);
+        QCOMPARE(match.captured(), QStringLiteral("GH"));
+
+        QVERIFY(a.contains(QRegularExpression("[G][HE]"), &match));
+        QVERIFY(match.hasMatch());
+        QCOMPARE(match.capturedStart(), 6);
+        QCOMPARE(match.capturedEnd(), 8);
+        QCOMPARE(match.captured(), QStringLiteral("GH"));
+
+        QVERIFY(a.contains(QRegularExpression("[f](.*)[FG]"), &match));
+        QVERIFY(match.hasMatch());
+        QCOMPARE(match.capturedStart(), 10);
+        QCOMPARE(match.capturedEnd(), 15);
+        QCOMPARE(match.captured(), QString("fGEFG"));
+        QCOMPARE(match.capturedStart(1), 11);
+        QCOMPARE(match.capturedEnd(1), 14);
+        QCOMPARE(match.captured(1), QStringLiteral("GEF"));
+
+        QVERIFY(a.contains(QRegularExpression("[f](.*)[F]"), &match));
+        QVERIFY(match.hasMatch());
+        QCOMPARE(match.capturedStart(), 10);
+        QCOMPARE(match.capturedEnd(), 14);
+        QCOMPARE(match.captured(), QString("fGEF"));
+        QCOMPARE(match.capturedStart(1), 11);
+        QCOMPARE(match.capturedEnd(1), 13);
+        QCOMPARE(match.captured(1), QStringLiteral("GE"));
+
+        QVERIFY(!a.contains(QRegularExpression("ZZZ"), &match));
+        // doesn't match, but ensure match didn't change
+        QVERIFY(match.hasMatch());
+        QCOMPARE(match.capturedStart(), 10);
+        QCOMPARE(match.capturedEnd(), 14);
+        QCOMPARE(match.captured(), QStringLiteral("fGEF"));
+        QCOMPARE(match.capturedStart(1), 11);
+        QCOMPARE(match.capturedEnd(1), 13);
+        QCOMPARE(match.captured(1), QStringLiteral("GE"));
+
+        // don't crash with a null pointer
+        QVERIFY(a.contains(QRegularExpression("[FG][HI]"), 0));
+        QVERIFY(!a.contains(QRegularExpression("ZZZ"), 0));
+    }
+
     CREATE_REF(QLatin1String("FG"));
     QVERIFY(a.contains(ref));
     QVERIFY(a.contains(ref, Qt::CaseInsensitive));