From f3c340c276847cbf69ef0a10d33e970ef1371bde Mon Sep 17 00:00:00 2001
From: Marc Mutz <marc.mutz@qt.io>
Date: Tue, 15 Mar 2022 07:46:03 +0100
Subject: [PATCH] QStringTokenizer::toContainer(): allow more types of target
 containers

The previous constraint called for the value_type of the container to
exactly match the value_type of the tokenizer, which means
toContainer() could only ever work on containers of views. But there
is value in allowing QStringList, even though it works only on QL1S
needles (QStringView -> QString isn't implicit). But users may have
other types that for better or worse implicitly convert from views, so
we shouldn't over-constrain the function.

[ChangeLog][QtCore][QStringTokenizer] toContainer() now works on
containers whose value_type can be constructed from the tokenizer's
value_type. It no longer requires an exact match.

Fixes: QTBUG-101702
Change-Id: Ie384cd1c4b51eaa57675f2a014141ceec8651c81
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
---
 src/corelib/text/qstringtokenizer.h                 |  2 +-
 .../text/qstringtokenizer/tst_qstringtokenizer.cpp  | 13 +++++++++++++
 2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/src/corelib/text/qstringtokenizer.h b/src/corelib/text/qstringtokenizer.h
index d14099ffbbe..0b98f0646f1 100644
--- a/src/corelib/text/qstringtokenizer.h
+++ b/src/corelib/text/qstringtokenizer.h
@@ -292,7 +292,7 @@ class QStringTokenizer
     using if_haystack_not_pinned = typename if_haystack_not_pinned_impl<Container, HPin>::type;
     template <typename Container, typename Iterator = decltype(std::begin(std::declval<Container>()))>
     using if_compatible_container = typename std::enable_if<
-            std::is_same<
+            std::is_convertible<
                 typename Base::value_type,
                 typename std::iterator_traits<Iterator>::value_type
             >::value,
diff --git a/tests/auto/corelib/text/qstringtokenizer/tst_qstringtokenizer.cpp b/tests/auto/corelib/text/qstringtokenizer/tst_qstringtokenizer.cpp
index 1d2658c38f2..e1619fee4d4 100644
--- a/tests/auto/corelib/text/qstringtokenizer/tst_qstringtokenizer.cpp
+++ b/tests/auto/corelib/text/qstringtokenizer/tst_qstringtokenizer.cpp
@@ -145,6 +145,19 @@ void tst_QStringTokenizer::toContainer() const
         auto v = tok.toContainer();
         QVERIFY((std::is_same_v<decltype(v), QList<QLatin1String>>));
     }
+    // QLatin1String value_type into QStringList
+    {
+        auto tok = qTokenize(QLatin1String{"a,b,c"}, u',');
+        QStringList result;
+        tok.toContainer(result);
+        QCOMPARE(result, QStringList({"a", "b", "c"}));
+    }
+    // QLatin1String value_type into QStringList: rvalue overload
+    {
+        QStringList result;
+        qTokenize(QLatin1String{"a,b,c"}, u',').toContainer(result);
+        QCOMPARE(result, QStringList({"a", "b", "c"}));
+    }
 }
 
 QTEST_APPLESS_MAIN(tst_QStringTokenizer)