From 926715683c5afed203358c24f64aa70b501f057c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?V=C3=A1clav=20Kubern=C3=A1t?= <sir.venceslas@gmail.com>
Date: Wed, 13 May 2020 09:03:27 +0200
Subject: [PATCH] c++ FEATURE allow constructing Submodule from Module (#1085)

---
 swig/cpp/src/Tree_Schema.cpp | 8 ++++++++
 swig/cpp/src/Tree_Schema.hpp | 3 +++
 2 files changed, 11 insertions(+)

diff --git a/swig/cpp/src/Tree_Schema.cpp b/swig/cpp/src/Tree_Schema.cpp
index 8ff2df389..3500ceda6 100644
--- a/swig/cpp/src/Tree_Schema.cpp
+++ b/swig/cpp/src/Tree_Schema.cpp
@@ -39,6 +39,14 @@ Submodule::Submodule(struct lys_submodule *submodule, S_Deleter deleter):
     submodule(submodule),
     deleter(deleter)
 {};
+Submodule::Submodule(S_Module module):
+    submodule((lys_submodule*)module->module),
+    deleter(module->deleter)
+{
+    if (module->type() != 1) {
+        throw std::invalid_argument("Attempted to cast a YANG module into a YANG submodule");
+    }
+}
 std::vector<S_Schema_Node> Module::data_instantiables(int options) {
     std::vector<S_Schema_Node> s_vector;
     struct lys_node *iter = NULL;
diff --git a/swig/cpp/src/Tree_Schema.hpp b/swig/cpp/src/Tree_Schema.hpp
index e3cb31929..aebea0fde 100644
--- a/swig/cpp/src/Tree_Schema.hpp
+++ b/swig/cpp/src/Tree_Schema.hpp
@@ -111,6 +111,7 @@ class Module
 
     friend Context;
     friend Data_Node;
+    friend Submodule;
 
 private:
     struct lys_module *module;
@@ -126,6 +127,8 @@ class Submodule
 public:
     /** wrapper for struct [lys_submodule](@ref lys_submodule), for internal use only */
     Submodule(struct lys_submodule *submodule, S_Deleter deleter);
+    /** creates a Submodule from `module` if it is a submodule */
+    Submodule(S_Module module);
     ~Submodule();
     /** get ctx variable from [lys_submodule](@ref lys_submodule)*/
     S_Context ctx() LY_NEW(submodule, ctx, Context);