QtTest: add support for printing QStringViews

[ChangeLog][QtTest][QCOMPARE] Now supports printing QStringViews in
case of test failures.

Change-Id: I4dc2542cd1013fd63c094c249e721d7102387bde
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

src/testlib/qtest.h

@@ -65,9 +65,14 @@ QT_BEGIN_NAMESPACE
 namespace QTest
 {
 
+template <> inline char *toString(const QStringView &str)
+{
+    return QTest::toPrettyUnicode(str);
+}
+
 template<> inline char *toString(const QString &str)
 {
-    return QTest::toPrettyUnicode(reinterpret_cast<const ushort *>(str.constData()), str.length());
+    return toString(QStringView(str));
 }
 
 template<> inline char *toString(const QLatin1String &str)

src/testlib/qtestcase.cpp

@@ -1271,6 +1271,16 @@ char *toPrettyCString(const char *p, int length)
     return buffer.take();
 }
 
+#if QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
+// this used to be the signature up to and including Qt 5.9
+// keep it for BC reasons:
+Q_TESTLIB_EXPORT
+char *toPrettyUnicode(const ushort *p, int length)
+{
+    return toPrettyUnicode(QStringView(p, length));
+}
+#endif
+
 /*!
     \internal
     Returns the same QString but with only the ASCII characters still shown;
@@ -1278,8 +1288,10 @@ char *toPrettyCString(const char *p, int length)
 
     Similar to QDebug::putString().
 */
-char *toPrettyUnicode(const ushort *p, int length)
+char *toPrettyUnicode(QStringView string)
 {
+    auto p = reinterpret_cast<const ushort *>(string.utf16());
+    auto length = string.size();
     // keep it simple for the vast majority of cases
     bool trimmed = false;
     QScopedArrayPointer<char> buffer(new char[256]);

src/testlib/qtestcase.h

@@ -277,7 +277,7 @@ namespace QTest
 
     Q_TESTLIB_EXPORT char *toHexRepresentation(const char *ba, int length);
     Q_TESTLIB_EXPORT char *toPrettyCString(const char *unicode, int length);
-    Q_TESTLIB_EXPORT char *toPrettyUnicode(const ushort *unicode, int length);
+    Q_TESTLIB_EXPORT char *toPrettyUnicode(QStringView string);
     Q_TESTLIB_EXPORT char *toString(const char *);
     Q_TESTLIB_EXPORT char *toString(const void *);
 

tests/auto/corelib/tools/qstringview/tst_qstringview.cpp

@@ -429,6 +429,8 @@ void tst_QStringView::conversion_tests(String string) const
                            sv.crbegin()));
         QVERIFY(std::equal(help::crbegin(string), help::crend(string),
                            sv.rbegin()));
+
+        QCOMPARE(sv, string);
     }
 
     QStringView sv;
@@ -441,8 +443,8 @@ void tst_QStringView::conversion_tests(String string) const
 
         // check relational operators:
 
-        QVERIFY(sv == string);
+        QCOMPARE(sv, string);
-        QVERIFY(string == sv);
+        QCOMPARE(string, sv);
 
         QVERIFY(!(sv != string));
         QVERIFY(!(string != sv));
@@ -461,16 +463,16 @@ void tst_QStringView::conversion_tests(String string) const
     // copy-construct from rvalue (QStringView never assumes ownership):
     {
         QStringView sv2 = std::move(string);
-        QVERIFY(sv2 == sv);
+        QCOMPARE(sv2, sv);
-        QVERIFY(sv2 == string);
+        QCOMPARE(sv2, string);
     }
 
     // copy-assign from rvalue (QStringView never assumes ownership):
     {
         QStringView sv2;
         sv2 = std::move(string);
-        QVERIFY(sv2 == sv);
+        QCOMPARE(sv2, sv);
-        QVERIFY(sv2 == string);
+        QCOMPARE(sv2, string);
     }
 }