qmllint: remove duplicate files for linting process

This might lead to QQmlJSLinter::prepareFileForLinting() rejecting the
file, and there is no need for a user to lint a file multiple times.

This is a preparation step for QTBUG-146688.

Task-number: QTBUG-146688
Change-Id: Ib868da5f37b291309f995b02aead77ed4007999d
Reviewed-by: Olivier De Cannière <olivier.decanniere@qt.io>
Reviewed-by: Semih Yavuz <semih.yavuz@qt.io>

1 files changed, 8 insertions, 1 deletions

diff --git a/tools/qmllint/main.cpp b/tools/qmllint/main.cpp
index 96c30cd2a9..de731e0940 100644
--- a/tools/qmllint/main.cpp
+++ b/tools/qmllint/main.cpp
@@ -350,7 +350,14 @@ All warnings can be set to four levels of severity:
         return 0;
     }
 
-    const auto positionalArguments = parser.positionalArguments();
+    const auto positionalArguments = [&parser]() {
+        auto positionalArguments = parser.positionalArguments();
+        auto begin = positionalArguments.begin(), end = positionalArguments.end();
+        std::sort(begin, end);
+        positionalArguments.erase(std::unique(begin, end), end);
+        return positionalArguments;
+    }();
+
     if (positionalArguments.isEmpty()) {
         parser.showHelp(-1);
     }