From 90c86d738e0f36eaa48c7f81f6f5cc035a339d6b Mon Sep 17 00:00:00 2001
From: David Faure <david.faure@kdab.com>
Date: Thu, 4 Apr 2019 10:53:57 +0200
Subject: [PATCH] QCommandLineParser: warn if defining a duplicate option

Fixes: QTBUG-74907
Change-Id: I3741a5241515dfaf4353458a9ef13ceaeb9fea0b
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
---
 src/corelib/tools/qcommandlineparser.cpp               |  4 +++-
 .../qcommandlineparser/tst_qcommandlineparser.cpp      | 10 ++++++++++
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/src/corelib/tools/qcommandlineparser.cpp b/src/corelib/tools/qcommandlineparser.cpp
index 6817d73143..489724ac47 100644
--- a/src/corelib/tools/qcommandlineparser.cpp
+++ b/src/corelib/tools/qcommandlineparser.cpp
@@ -362,8 +362,10 @@ bool QCommandLineParser::addOption(const QCommandLineOption &option)
 
     if (!optionNames.isEmpty()) {
         for (const QString &name : optionNames) {
-            if (d->nameHash.contains(name))
+            if (d->nameHash.contains(name)) {
+                qWarning() << "QCommandLineParser: already having an option named" << name;
                 return false;
+            }
         }
 
         d->commandLineOptionList.append(option);
diff --git a/tests/auto/corelib/tools/qcommandlineparser/tst_qcommandlineparser.cpp b/tests/auto/corelib/tools/qcommandlineparser/tst_qcommandlineparser.cpp
index 7980f1f8f4..811e9a0010 100644
--- a/tests/auto/corelib/tools/qcommandlineparser/tst_qcommandlineparser.cpp
+++ b/tests/auto/corelib/tools/qcommandlineparser/tst_qcommandlineparser.cpp
@@ -44,6 +44,7 @@ private slots:
 
     // In-process tests
     void testInvalidOptions();
+    void testDuplicateOption();
     void testPositionalArguments();
     void testBooleanOption_data();
     void testBooleanOption();
@@ -104,6 +105,15 @@ void tst_QCommandLineParser::testInvalidOptions()
     QVERIFY(!parser.addOption(QCommandLineOption(QStringLiteral("-v"), QStringLiteral("Displays version information."))));
 }
 
+void tst_QCommandLineParser::testDuplicateOption()
+{
+    QCoreApplication app(empty_argc, empty_argv);
+    QCommandLineParser parser;
+    QVERIFY(parser.addOption(QCommandLineOption(QStringLiteral("h"), QStringLiteral("Hostname."), QStringLiteral("hostname"))));
+    QTest::ignoreMessage(QtWarningMsg, "QCommandLineParser: already having an option named \"h\"");
+    parser.addHelpOption();
+}
+
 void tst_QCommandLineParser::testPositionalArguments()
 {
     QCoreApplication app(empty_argc, empty_argv);