Q(Any|Utf8)StringView: move array size deduction feature to fromArray

The constructor taking an array literal will now stop at the first
null-terminator encountered.

And fromArray is introduced which only supports array literals.
Constructs a view of the full size. Explicit so it shouldn't be
surprising.

Change-Id: I1497c33a5c12453a95e87c990abe6335b2817081
Reviewed-by: Andrei Golubev <andrei.golubev@qt.io>
Reviewed-by: Lars Knoll <lars.knoll@qt.io>

1 files changed, 8 insertions, 2 deletions

diff --git a/src/corelib/text/qstringview.h b/src/corelib/text/qstringview.h
index f88871ff5d..a4d0a78e5b 100644
--- a/src/corelib/text/qstringview.h
+++ b/src/corelib/text/qstringview.h
@@ -172,9 +172,11 @@ private:
     }
 
     template <typename Char, size_t N>
-    static constexpr qsizetype lengthHelperContainer(const Char (&)[N]) noexcept
+    static constexpr qsizetype lengthHelperContainer(const Char (&str)[N]) noexcept
     {
-        return qsizetype(N - 1);
+        const auto it = std::char_traits<Char>::find(str, N, Char(0));
+        const auto end = it ? it : std::next(str, N);
+        return qsizetype(std::distance(str, end));
     }
 
     template <typename Char>
@@ -223,6 +225,10 @@ public:
     constexpr QStringView(const Container &c) noexcept
         : QStringView(std::data(c), lengthHelperContainer(c)) {}
 
+    template <typename Char, size_t Size, if_compatible_char<Char> = true>
+    [[nodiscard]] constexpr static QStringView fromArray(const Char (&string)[Size]) noexcept
+    { return QStringView(string, Size); }
+
     Q_REQUIRED_RESULT inline QString toString() const; // defined in qstring.h
 #if defined(Q_OS_DARWIN) || defined(Q_QDOC)
     // defined in qcore_foundation.mm