Fix check for temporary QString when checking QRegularExpression

Every QRegularExpression constructed from a temporary QString is not
warnable.

2 files changed, 31 insertions, 1 deletions

diff --git a/src/checks/level0/use-static-qregularexpression.cpp b/src/checks/level0/use-static-qregularexpression.cpp
index 0f2aed83..fb851afb 100644
--- a/src/checks/level0/use-static-qregularexpression.cpp
+++ b/src/checks/level0/use-static-qregularexpression.cpp
@@ -63,6 +63,15 @@ static Expr* getVarInitExpr(VarDecl *VDef)
 static bool isQStringFromStringLiteral(Expr *qstring)
 {
     if (isArgTemporaryObj(qstring)) {
+        // Is it compile time known QString i.e., not from a function call
+        auto qstringCtor = clazy::getFirstChildOfType<CXXConstructExpr>(qstring);
+        if (!qstringCtor)
+            return false;
+
+        auto *stringLit = clazy::getFirstChildOfType<StringLiteral>(qstringCtor);
+        if (!stringLit)
+            return false;
+
         return true;
     }
 
@@ -82,7 +91,7 @@ static bool isTemporaryQRegexObj(Expr *qregexVar, const LangOptions &lo) {
       return false;
   }
 
-  // Check if its first arg is "QString" && a temporary OR non-static local
+  // Check if its first arg is "QString"
   auto qstrArg = ctor->getArg(0);
   if (!qstrArg || clazy::typeName(qstrArg->getType(), lo, true) != "QString") {
       return false;
diff --git a/tests/use-static-qregularexpression/main.cpp b/tests/use-static-qregularexpression/main.cpp
index a1a18916..b3c4947b 100644
--- a/tests/use-static-qregularexpression/main.cpp
+++ b/tests/use-static-qregularexpression/main.cpp
@@ -99,3 +99,24 @@ void test_qregexmatch(QString selectedText)
     QVariant v;
     v.toRegularExpression().match(selectedText); // No Warn
 }
+
+extern QString someText();
+void test_qregexmatch_rvalueString(QString s)
+{
+    // XValue + RValue arg
+    QString text;
+    QRegularExpression(someText()).match(text); // Ok
+
+    // LValue + RValue arg
+    QRegularExpression re(someText());
+    re.match(text);
+
+    QRegularExpression re1("^" + someText());
+    re1.match(text);
+
+    QRegularExpression re2("^" + s);
+    re2.match(text);
+
+    QRegularExpression re3((QString(s)));
+    re3.match(text);
+}