QLocalePrivate: add overloaded codeToScript() and codeToLanguage()

... for QStringRef and QChar array.

Now we can use QStringRef arg or QChar array arg to avoid
unnecessary allocations.

Also mark these functions as Q_DECL_NOTHROW.

Change-Id: Ibe75346d80cc413e303fad886ecb82dbdb89af24
Reviewed-by: Edward Welbourne <edward.welbourne@theqtcompany.com>
Reviewed-by: Marc Mutz <marc.mutz@kdab.com>

2 files changed, 12 insertions, 10 deletions

diff --git a/src/corelib/tools/qlocale.cpp b/src/corelib/tools/qlocale.cpp
index 8d64e02814..e5a21dfef4 100644
--- a/src/corelib/tools/qlocale.cpp
+++ b/src/corelib/tools/qlocale.cpp
@@ -91,9 +91,8 @@ QT_BEGIN_INCLUDE_NAMESPACE
 #include "qlocale_data_p.h"
 QT_END_INCLUDE_NAMESPACE
 
-QLocale::Language QLocalePrivate::codeToLanguage(const QString &code)
+QLocale::Language QLocalePrivate::codeToLanguage(const QChar *code, int len) Q_DECL_NOTHROW
 {
-    int len = code.length();
     if (len != 2 && len != 3)
         return QLocale::C;
     ushort uc1 = code[0].toLower().unicode();
@@ -134,17 +133,16 @@ QLocale::Language QLocalePrivate::codeToLanguage(const QString &code)
     return QLocale::C;
 }
 
-QLocale::Script QLocalePrivate::codeToScript(const QString &code)
+QLocale::Script QLocalePrivate::codeToScript(const QChar *code, int len) Q_DECL_NOTHROW
 {
-    int len = code.length();
     if (len != 4)
         return QLocale::AnyScript;
 
     // script is titlecased in our data
-    unsigned char c0 = code.at(0).toUpper().toLatin1();
-    unsigned char c1 = code.at(1).toLower().toLatin1();
-    unsigned char c2 = code.at(2).toLower().toLatin1();
-    unsigned char c3 = code.at(3).toLower().toLatin1();
+    unsigned char c0 = code[0].toUpper().toLatin1();
+    unsigned char c1 = code[1].toLower().toLatin1();
+    unsigned char c2 = code[2].toLower().toLatin1();
+    unsigned char c3 = code[3].toLower().toLatin1();
 
     const unsigned char *c = script_code_list;
     for (int i = 0; i < QLocale::LastScript; ++i, c += 4) {
diff --git a/src/corelib/tools/qlocale_p.h b/src/corelib/tools/qlocale_p.h
index edffcea3e5..f95edf4d14 100644
--- a/src/corelib/tools/qlocale_p.h
+++ b/src/corelib/tools/qlocale_p.h
@@ -353,8 +353,12 @@ public:
     static QString languageToCode(QLocale::Language language);
     static QString scriptToCode(QLocale::Script script);
     static QString countryToCode(QLocale::Country country);
-    static QLocale::Language codeToLanguage(const QString &code);
-    static QLocale::Script codeToScript(const QString &code);
+    static QLocale::Language codeToLanguage(const QChar *code, int len) Q_DECL_NOTHROW;
+    static QLocale::Language codeToLanguage(const QString &code) Q_DECL_NOTHROW { return codeToLanguage(code.data(), code.size()); }
+    static QLocale::Language codeToLanguage(const QStringRef &code) Q_DECL_NOTHROW { return codeToLanguage(code.data(), code.size()); }
+    static QLocale::Script codeToScript(const QChar *code, int len) Q_DECL_NOTHROW;
+    static QLocale::Script codeToScript(const QString &code) Q_DECL_NOTHROW { return codeToScript(code.data(), code.size()); }
+    static QLocale::Script codeToScript(const QStringRef &code) Q_DECL_NOTHROW { return codeToScript(code.data(), code.size()); }
     static QLocale::Country codeToCountry(const QChar *code, int len) Q_DECL_NOTHROW;
     static QLocale::Country codeToCountry(const QString &code) Q_DECL_NOTHROW { return codeToCountry(code.data(), code.size()); }
     static QLocale::Country codeToCountry(const QStringRef &code) Q_DECL_NOTHROW { return codeToCountry(code.data(), code.size()); }