improve loplugin:referencecasting

to catch a few more cases

Change-Id: I0323fba51bb2b4ba255e1db5aa0d890c5c6a2e1b
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/93726
Tested-by: Jenkins
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>

2 files changed, 23 insertions, 0 deletions

diff --git a/compilerplugins/clang/referencecasting.cxx b/compilerplugins/clang/referencecasting.cxx
index 1f8e13173811..33997cdb458d 100644
--- a/compilerplugins/clang/referencecasting.cxx
+++ b/compilerplugins/clang/referencecasting.cxx
@@ -329,6 +329,20 @@ static const RecordType* extractTemplateType(const clang::Type* cceType)
             return recordType;
     }
 
+    // extract Foo from Reference<Foo>
+    if (auto subst = dyn_cast<SubstTemplateTypeParmType>(cceType))
+    {
+        if (auto recType = dyn_cast<RecordType>(subst->desugar().getTypePtr()))
+        {
+            if (auto ctsd = dyn_cast<ClassTemplateSpecializationDecl>(recType->getDecl()))
+            {
+                auto const& args = ctsd->getTemplateArgs();
+                if (args.size() > 0 && args[0].getKind() == TemplateArgument::ArgKind::Type)
+                    return dyn_cast_or_null<RecordType>(args[0].getAsType().getTypePtr());
+            }
+        }
+    }
+
     if (auto elaboratedType = dyn_cast<ElaboratedType>(cceType))
         cceType = elaboratedType->desugar().getTypePtr();
     auto cceTST = dyn_cast<TemplateSpecializationType>(cceType);
diff --git a/compilerplugins/clang/test/referencecasting.cxx b/compilerplugins/clang/test/referencecasting.cxx
index 87324bb86fd6..0272bc89cc98 100644
--- a/compilerplugins/clang/test/referencecasting.cxx
+++ b/compilerplugins/clang/test/referencecasting.cxx
@@ -147,4 +147,13 @@ struct Test13
     }
 };
 
+void test14(css::uno::Sequence<css::uno::Reference<css::io::XStreamListener>> seq)
+{
+    for (sal_Int32 i = 0; i < seq.getLength(); ++i)
+    {
+        // expected-error@+1 {{the source reference is already a subtype of the destination reference, just use = [loplugin:referencecasting]}}
+        css::uno::Reference<css::io::XStreamListener> xDataSeries(seq[i], css::uno::UNO_QUERY);
+    }
+}
+
 /* vim:set shiftwidth=4 softtabstop=4 expandtab cinoptions=b1,g0,N-s cinkeys+=0=break: */