loplugin:unnecessaryparen small improvement

when calling a function, and passing only one arg, but the
function has defaulted args, we were ignoring this case.

Change-Id: I86517f18e30531127664088ddc09ef96dbd8bdf5
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/115033
Tested-by: Jenkins
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>

2 files changed, 10 insertions, 1 deletions

diff --git a/compilerplugins/clang/test/unnecessaryparen.cxx b/compilerplugins/clang/test/unnecessaryparen.cxx
index f932cd312558..ccc2b4ce6556 100644
--- a/compilerplugins/clang/test/unnecessaryparen.cxx
+++ b/compilerplugins/clang/test/unnecessaryparen.cxx
@@ -113,6 +113,8 @@ int main()
 
     BrowseMode nBits = ( BrowseMode::Modules | BrowseMode::Top ); // expected-error {{parentheses immediately inside vardecl statement [loplugin:unnecessaryparen]}}
     (void)nBits;
+
+    OUString::number((v2+1)); // expected-error {{parentheses immediately inside single-arg call [loplugin:unnecessaryparen]}}
 };
 
 struct B { operator bool() const; };
diff --git a/compilerplugins/clang/unnecessaryparen.cxx b/compilerplugins/clang/unnecessaryparen.cxx
index d39dd074eb43..eb53c449cd77 100644
--- a/compilerplugins/clang/unnecessaryparen.cxx
+++ b/compilerplugins/clang/unnecessaryparen.cxx
@@ -368,9 +368,16 @@ bool UnnecessaryParen::VisitCallExpr(const CallExpr* callExpr)
 {
     if (ignoreLocation(callExpr))
         return true;
-    if (callExpr->getNumArgs() != 1 || isa<CXXOperatorCallExpr>(callExpr))
+    if (callExpr->getNumArgs() == 0 || isa<CXXOperatorCallExpr>(callExpr))
         return true;
 
+    // if we are calling a >1 arg method, are we using the defaults?
+    if (callExpr->getNumArgs() > 1)
+    {
+        if (!isa<CXXDefaultArgExpr>(callExpr->getArg(1)))
+            return true;
+    }
+
     auto parenExpr = dyn_cast<ParenExpr>(ignoreAllImplicit(callExpr->getArg(0)));
     if (!parenExpr)
         return true;