C++: Fix (Find)LocalSymbols for lambda parameters

Change-Id: I5cb69749b4f15e4f70dea410aa6f943c4189c502
Reviewed-by: Erik Verbruggen <erik.verbruggen@digia.com>

src/libs/3rdparty/cplusplus/AST.h

@@ -4455,6 +4455,9 @@ public:
     ExceptionSpecificationAST *exception_specification;
     TrailingReturnTypeAST *trailing_return_type;
 
+public: // annotations
+    Function *symbol;
+
 public:
     LambdaDeclaratorAST()
         : lparen_token(0)

src/libs/3rdparty/cplusplus/Bind.cpp

@@ -1098,6 +1098,7 @@ Function *Bind::lambdaDeclarator(LambdaDeclaratorAST *ast)
     if (ast->trailing_return_type)
         _type = this->trailingReturnType(ast->trailing_return_type, _type);
     fun->setReturnType(_type);
+    ast->symbol = fun;
 
     // unsigned lparen_token = ast->lparen_token;
     FullySpecifiedType type;

src/plugins/cpptools/cpplocalsymbols.cpp

@@ -175,6 +175,19 @@ protected:
             _scopeStack.removeLast();
     }
 
+    virtual bool visit(LambdaExpressionAST *ast)
+    {
+        if (ast->lambda_declarator && ast->lambda_declarator->symbol)
+            enterScope(ast->lambda_declarator->symbol);
+        return true;
+    }
+
+    virtual void endVisit(LambdaExpressionAST *ast)
+    {
+        if (ast->lambda_declarator && ast->lambda_declarator->symbol)
+            _scopeStack.removeLast();
+    }
+
     virtual bool visit(CompoundStatementAST *ast)
     {
         if (ast->symbol)

src/plugins/cpptools/cpplocalsymbols_test.cpp

@@ -157,6 +157,18 @@ void CppToolsPlugin::test_cpplocalsymbols_data()
             << Result(_("local"), 3, 8, 5)
             << Result(_("local"), 4, 12, 5)
             << Result(_("arg"), 4, 20, 3));
+
+    QTest::newRow("lambda")
+        << _("void f()\n"
+             "{\n"
+             "    auto func = [](int arg) { return arg; };\n"
+             "    func(1);\n"
+             "}\n")
+        << (QList<Result>()
+            << Result(_("func"), 2, 10, 4)
+            << Result(_("arg"), 2, 24, 3)
+            << Result(_("arg"), 2, 38, 3)
+            << Result(_("func"), 3, 5, 4));
 }
 
 void CppToolsPlugin::test_cpplocalsymbols()