QRegularExpression: introduce (global)matchView

QRegularExpression::match (and globalMatch) is currently overloaded
for QString and QStringView. This creates a subtle API asymmetry:

  QRegularExpression re;

  auto m1 = re.match(getQString());       // OK
  auto m2 = re.match(getStdU16String());  // Dangling

This goes against our decision that every time that there's a possible
lifetime issue at play, it should be "evident". Solving the lifetime
issue here is possible, but tricky -- since QRegularExpression
is out-of-line, one needs a type-erased container for the input
string (basically, std::any) to keep it alive and so on.

Instead I went for the simpler solution: deprecate match(QStringView)
and introduce matchView(QStringView) (same for globalMatch). This
makes it clear that the call is matching over a view and therefore
users are supposed to keep the source object alive.

Drive-by, remove the documentation that says that the QString
overloads might not keep the string alive: they do and forever will.

[ChangeLog][QtCore][QRegularExpression] Added the matchView()
and globalMatchView() functions that operate on string views.
The match(QStringView) and globalMatch(QStringView) overloads
have been deprecated.

Change-Id: I054b8605c2fdea59b556dcfea8920ef4eee78ee9
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

1 files changed, 17 insertions, 16 deletions

diff --git a/tests/auto/corelib/text/qregularexpression/tst_qregularexpression.cpp b/tests/auto/corelib/text/qregularexpression/tst_qregularexpression.cpp
index 37fa8147ed..7f3bef66e6 100644
--- a/tests/auto/corelib/text/qregularexpression/tst_qregularexpression.cpp
+++ b/tests/auto/corelib/text/qregularexpression/tst_qregularexpression.cpp
@@ -393,6 +393,7 @@ static void testMatch(const QRegularExpression &regexp,
                             result);
 }
 
+// ### Qt 7: there should no longer be the need for these
 typedef QRegularExpressionMatch (QRegularExpression::*QREMatchStringPMF)(const QString &, qsizetype, QRegularExpression::MatchType, QRegularExpression::MatchOptions) const;
 typedef QRegularExpressionMatch (QRegularExpression::*QREMatchStringViewPMF)(QStringView, qsizetype, QRegularExpression::MatchType, QRegularExpression::MatchOptions) const;
 typedef QRegularExpressionMatchIterator (QRegularExpression::*QREGlobalMatchStringPMF)(const QString &, qsizetype, QRegularExpression::MatchType, QRegularExpression::MatchOptions) const;
@@ -1096,7 +1097,7 @@ void tst_QRegularExpression::normalMatch()
 
     testMatch<QRegularExpressionMatch>(regexp,
                                        static_cast<QREMatchStringPMF>(&QRegularExpression::match),
-                                       static_cast<QREMatchStringViewPMF>(&QRegularExpression::match),
+                                       static_cast<QREMatchStringViewPMF>(&QRegularExpression::matchView),
                                        subject,
                                        offset,
                                        QRegularExpression::NormalMatch,
@@ -1368,7 +1369,7 @@ void tst_QRegularExpression::partialMatch()
 
     testMatch<QRegularExpressionMatch>(regexp,
                                        static_cast<QREMatchStringPMF>(&QRegularExpression::match),
-                                       static_cast<QREMatchStringViewPMF>(&QRegularExpression::match),
+                                       static_cast<QREMatchStringViewPMF>(&QRegularExpression::matchView),
                                        subject,
                                        offset,
                                        matchType,
@@ -1645,7 +1646,7 @@ void tst_QRegularExpression::globalMatch()
 
     testMatch<QRegularExpressionMatchIterator>(regexp,
                                                static_cast<QREGlobalMatchStringPMF>(&QRegularExpression::globalMatch),
-                                               static_cast<QREGlobalMatchStringViewPMF>(&QRegularExpression::globalMatch),
+                                               static_cast<QREGlobalMatchStringViewPMF>(&QRegularExpression::globalMatchView),
                                                subject,
                                                offset,
                                                matchType,
@@ -1985,7 +1986,7 @@ void tst_QRegularExpression::QStringAndQStringViewEquivalence()
             QCOMPARE(match.capturedEnd(), 4);
         }
         {
-            const QRegularExpressionMatch match = re.match(QStringView(subject));
+            const QRegularExpressionMatch match = re.matchView(QStringView(subject));
             consistencyCheck(match);
             QVERIFY(match.isValid());
             QVERIFY(match.hasMatch());
@@ -2003,7 +2004,7 @@ void tst_QRegularExpression::QStringAndQStringViewEquivalence()
             QCOMPARE(match.capturedEnd(), 4);
         }
         {
-            const QRegularExpressionMatch match = re.match(QStringView(subject), 1);
+            const QRegularExpressionMatch match = re.matchView(QStringView(subject), 1);
             consistencyCheck(match);
             QVERIFY(match.isValid());
             QVERIFY(match.hasMatch());
@@ -2021,7 +2022,7 @@ void tst_QRegularExpression::QStringAndQStringViewEquivalence()
             QCOMPARE(match.capturedEnd(), 6);
         }
         {
-            const QRegularExpressionMatch match = re.match(QStringView(subject).mid(1));
+            const QRegularExpressionMatch match = re.matchView(QStringView(subject).mid(1));
             consistencyCheck(match);
             QVERIFY(match.isValid());
             QVERIFY(match.hasMatch());
@@ -2039,7 +2040,7 @@ void tst_QRegularExpression::QStringAndQStringViewEquivalence()
             QCOMPARE(match.capturedEnd(), 6);
         }
         {
-            const QRegularExpressionMatch match = re.match(QStringView(subject).mid(1), 1);
+            const QRegularExpressionMatch match = re.matchView(QStringView(subject).mid(1), 1);
             consistencyCheck(match);
             QVERIFY(match.isValid());
             QVERIFY(match.hasMatch());
@@ -2057,7 +2058,7 @@ void tst_QRegularExpression::QStringAndQStringViewEquivalence()
             QCOMPARE(match.capturedEnd(), 7);
         }
         {
-            const QRegularExpressionMatch match = re.match(QStringView(subject), 4);
+            const QRegularExpressionMatch match = re.matchView(QStringView(subject), 4);
             consistencyCheck(match);
             QVERIFY(match.isValid());
             QVERIFY(match.hasMatch());
@@ -2072,7 +2073,7 @@ void tst_QRegularExpression::QStringAndQStringViewEquivalence()
             QVERIFY(!match.hasMatch());
         }
         {
-            const QRegularExpressionMatch match = re.match(QStringView(subject).mid(4));
+            const QRegularExpressionMatch match = re.matchView(QStringView(subject).mid(4));
             consistencyCheck(match);
             QVERIFY(match.isValid());
             QVERIFY(!match.hasMatch());
@@ -2105,7 +2106,7 @@ void tst_QRegularExpression::QStringAndQStringViewEquivalence()
             QVERIFY(!i.hasNext());
         }
         {
-            QRegularExpressionMatchIterator i = re.globalMatch(QStringView(subject));
+            QRegularExpressionMatchIterator i = re.globalMatchView(QStringView(subject));
             QVERIFY(i.isValid());
 
             consistencyCheck(i);
@@ -2157,7 +2158,7 @@ void tst_QRegularExpression::QStringAndQStringViewEquivalence()
             QVERIFY(!i.hasNext());
         }
         {
-            QRegularExpressionMatchIterator i = re.globalMatch(QStringView(subject), 1);
+            QRegularExpressionMatchIterator i = re.globalMatchView(QStringView(subject), 1);
             QVERIFY(i.isValid());
 
             consistencyCheck(i);
@@ -2199,7 +2200,7 @@ void tst_QRegularExpression::QStringAndQStringViewEquivalence()
             QVERIFY(!i.hasNext());
         }
         {
-            QRegularExpressionMatchIterator i = re.globalMatch(QStringView(subject).mid(1));
+            QRegularExpressionMatchIterator i = re.globalMatchView(QStringView(subject).mid(1));
             QVERIFY(i.isValid());
 
             consistencyCheck(i);
@@ -2231,7 +2232,7 @@ void tst_QRegularExpression::QStringAndQStringViewEquivalence()
             QVERIFY(!i.hasNext());
         }
         {
-            QRegularExpressionMatchIterator i = re.globalMatch(QStringView(subject).mid(1), 1);
+            QRegularExpressionMatchIterator i = re.globalMatchView(QStringView(subject).mid(1), 1);
             QVERIFY(i.isValid());
 
             consistencyCheck(i);
@@ -2263,7 +2264,7 @@ void tst_QRegularExpression::QStringAndQStringViewEquivalence()
             QVERIFY(!i.hasNext());
         }
         {
-            QRegularExpressionMatchIterator i = re.globalMatch(QStringView(subject).mid(1), 1);
+            QRegularExpressionMatchIterator i = re.globalMatchView(QStringView(subject).mid(1), 1);
             QVERIFY(i.isValid());
 
             consistencyCheck(i);
@@ -2296,7 +2297,7 @@ void tst_QRegularExpression::QStringAndQStringViewEquivalence()
             QVERIFY(!i.hasNext());
         }
         {
-            QRegularExpressionMatchIterator i = re.globalMatch(QStringView(subject), 4);
+            QRegularExpressionMatchIterator i = re.globalMatchView(QStringView(subject), 4);
             QVERIFY(i.isValid());
 
             consistencyCheck(i);
@@ -2318,7 +2319,7 @@ void tst_QRegularExpression::QStringAndQStringViewEquivalence()
             QVERIFY(!i.hasNext());
         }
         {
-            QRegularExpressionMatchIterator i = re.globalMatch(QStringView(subject).mid(4));
+            QRegularExpressionMatchIterator i = re.globalMatchView(QStringView(subject).mid(4));
             consistencyCheck(i);
             QVERIFY(i.isValid());
             QVERIFY(!i.hasNext());