add test for nested namespaces

tests/generator_scripts/index.yaml

@@ -48,6 +48,10 @@ Conditionals:
       - regex: if\s*\(\s*noodle\s==\sNoodles::RIGATONI\s\|\|\snoodle\s==\sNoodles::SPAGHETTI\s*\)
         count: 1
 
+NestedNamespaces:
+  sfg-args:
+    output-mode: header-only
+
 # Kernel Generation
 
 ScaleKernel:

tests/generator_scripts/source/NestedNamespaces.harness.cpp

+#include "NestedNamespaces.hpp"
+
+static_assert( outer::X == 13 );
+static_assert( outer::inner::Y == 52 );
+static_assert( outer::Z == 41 );
+static_assert( outer::second_inner::W == 91 );
+static_assert( outer::inner::innermost::V == 29 );
+static_assert( GLOBAL == 42 );
+
+int main() {
+    return 0;
+}

tests/generator_scripts/source/NestedNamespaces.py

+from pystencilssfg import SourceFileGenerator
+
+with SourceFileGenerator() as sfg:
+
+    with sfg.namespace("outer"):
+        sfg.code("constexpr int X = 13;")
+
+        with sfg.namespace("inner"):
+            sfg.code("constexpr int Y = 52;")
+
+        sfg.code("constexpr int Z = 41;")
+
+    with sfg.namespace("outer::second_inner"):
+        sfg.code("constexpr int W = 91;")
+
+    with sfg.namespace("outer::inner::innermost"):
+        sfg.code("constexpr int V = 29;")
+
+    sfg.code("constexpr int GLOBAL = 42;")