uic: use a real ordered set

... instead of QMap<Key, bool>. Since Qt doesn't have such
a container, use std::set instead, which also simplifies
some code, in particular, because, unlike the Qt containers,
it does the right thing on attempted duplicate insertion:
nothing.

Saves 6.5KiB in text size (1.1% of total) on optimized
GCC 5.3 Linux AMD64 builds.

Change-Id: I9578a9a58c1c06abe58f22a5b6127d43c2f4be12
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@qt.io>

2 files changed, 15 insertions, 13 deletions

diff --git a/src/tools/uic/cpp/cppwriteincludes.cpp b/src/tools/uic/cpp/cppwriteincludes.cpp
index a99d6adf07..dcbe400224 100644
--- a/src/tools/uic/cpp/cppwriteincludes.cpp
+++ b/src/tools/uic/cpp/cppwriteincludes.cpp
@@ -114,8 +114,9 @@ void WriteIncludes::acceptUI(DomUI *node)
 
     TreeWalker::acceptUI(node);
 
-    if (!m_uic->option().includeFile.isEmpty())
-        m_globalIncludes.insert(m_uic->option().includeFile, true);
+    const auto includeFile = m_uic->option().includeFile;
+    if (!includeFile.isEmpty())
+        m_globalIncludes.insert(includeFile);
 
     writeHeaders(m_globalIncludes, true);
     writeHeaders(m_localIncludes, false);
@@ -272,10 +273,11 @@ void WriteIncludes::insertInclude(const QString &header, bool global)
         fprintf(stderr, "%s %s %d\n", Q_FUNC_INFO, qPrintable(header), global);
 
     OrderedSet &includes = global ?  m_globalIncludes : m_localIncludes;
-    if (includes.contains(header))
+    // Insert (if not already done).
+    const bool isNewHeader = includes.insert(header).second;
+    if (!isNewHeader)
         return;
-    // Insert. Also remember base name for quick check of suspicious custom plugins
-    includes.insert(header, false);
+    // Also remember base name for quick check of suspicious custom plugins
     const QString lowerBaseName = QFileInfo(header).completeBaseName ().toLower();
     m_includeBaseNames.insert(lowerBaseName);
 }
@@ -286,13 +288,11 @@ void WriteIncludes::writeHeaders(const OrderedSet &headers, bool global)
     const QChar closingQuote = global ? QLatin1Char('>') : QLatin1Char('"');
 
     // Check for the old headers 'qslider.h' and replace by 'QtGui/QSlider'
-    const OrderedSet::const_iterator cend = headers.constEnd();
-    for (OrderedSet::const_iterator sit = headers.constBegin(); sit != cend; ++sit) {
-        const StringMap::const_iterator hit = m_oldHeaderToNewHeader.constFind(sit.key());
-        const bool mapped =  hit != m_oldHeaderToNewHeader.constEnd();
-        const  QString header =  mapped ? hit.value() : sit.key();
-        if (!QStringRef(&header).trimmed().isEmpty())
-            m_output << "#include " << openingQuote << header << closingQuote << QLatin1Char('\n');
+    for (const QString &header : headers) {
+        const QString value = m_oldHeaderToNewHeader.value(header, header);
+        const auto trimmed = QStringRef(&value).trimmed();
+        if (!trimmed.isEmpty())
+            m_output << "#include " << openingQuote << trimmed << closingQuote << QLatin1Char('\n');
     }
 }
 
diff --git a/src/tools/uic/cpp/cppwriteincludes.h b/src/tools/uic/cpp/cppwriteincludes.h
index 397c6a26e1..7a6a499536 100644
--- a/src/tools/uic/cpp/cppwriteincludes.h
+++ b/src/tools/uic/cpp/cppwriteincludes.h
@@ -35,6 +35,8 @@
 #include <qset.h>
 #include <qstring.h>
 
+#include <set>
+
 QT_BEGIN_NAMESPACE
 
 class QTextStream;
@@ -72,7 +74,7 @@ private:
     void add(const QString &className, bool determineHeader = true, const QString &header = QString(), bool global = false);
 
 private:
-    typedef QMap<QString, bool> OrderedSet;
+    typedef std::set<QString> OrderedSet;
     void insertIncludeForClass(const QString &className, QString header = QString(), bool global = false);
     void insertInclude(const QString &header, bool global);
     void writeHeaders(const OrderedSet &headers, bool global);