clang-tidy-10: namespace & nodiscard

C++17 modernizations that it found:
- `modernize-concat-nested-namespaces`
- `modernize-use-nodiscard`

examples/8a_benchmark_write_parallel.cpp

@@ -298,7 +298,7 @@ class TestInput
    * m_Seg can be set from input
    * exception is when h5 collective mode is on. m_Seg=1
    */
-  unsigned int GetSeg() const
+  [[nodiscard]] unsigned int GetSeg() const
   {
     if (m_Backend == ".h5")
         if (auxiliary::getEnvString( "OPENPMD_HDF5_INDEPENDENT", "ON" ) != "ON")

src/IO/ADIOS/ADIOS2Auxiliary.cpp

@@ -26,9 +26,7 @@
 
 #include <iostream>
 
-namespace openPMD
-{
-namespace detail
+namespace openPMD::detail
 {
     template< typename T >
     std::string
@@ -258,6 +256,5 @@ namespace detail
             throw std::runtime_error( "Unreachable!" );
         }
     }
-} // namespace detail
-} // namespace openPMD
+} // namespace openPMD::detail
 #endif

src/IO/ADIOS/ADIOS2PreloadAttributes.cpp

@@ -34,9 +34,7 @@
 #include <numeric>
 #include <type_traits>
 
-namespace openPMD
-{
-namespace detail
+namespace openPMD::detail
 {
     namespace
     {
@@ -288,7 +286,6 @@ namespace detail
         }
         return it->second.dt;
     }
-} // namespace detail
-} // namespace openPMD
+} // namespace openPMD::detail
 
 #endif // openPMD_HAVE_ADIOS2

src/auxiliary/Date.cpp

@@ -26,9 +26,7 @@
 #include <sstream>
 
 
-namespace openPMD
-{
-namespace auxiliary
+namespace openPMD::auxiliary
 {
     std::string getDateString( std::string const & format )
     {
@@ -48,5 +46,4 @@ namespace auxiliary
 
         return dateString.str();
     }
-} // namespace auxiliary
 } // namespace openPMD

src/auxiliary/Filesystem.cpp

@@ -36,9 +36,7 @@
 #include <system_error>
 
 
-namespace openPMD
-{
-namespace auxiliary
+namespace openPMD::auxiliary
 {
 bool
 directory_exists(std::string const& path)
@@ -257,5 +255,4 @@ collective_file_read( std::string const & path, MPI_Comm comm )
 
 #endif
 
-} // namespace auxiliary
 } // namespace openPMD

src/auxiliary/JSON.cpp

@@ -37,9 +37,7 @@
 #include <utility> // std::forward
 #include <vector>
 
-namespace openPMD
-{
-namespace json
+namespace openPMD::json
 {
     TracingJSON::TracingJSON()
         : TracingJSON( ParsedConfig{} )
@@ -597,5 +595,4 @@ namespace json
             parseOptions( overwrite, /* considerFiles = */ false ).config );
         return res.dump();
     }
-} // namespace json
 } // namespace openPMD

src/backend/Container.cpp

@@ -22,9 +22,7 @@
 #include "openPMD/backend/Container.hpp"
 #include "openPMD/RecordComponent.hpp"
 
-namespace openPMD
-{
-namespace detail
+namespace openPMD::detail
 {
 template<>
 std::vector< std::string > keyAsString< std::string const & >(
@@ -58,4 +56,3 @@ std::vector< std::string > keyAsString< std::string >(
     }
 }
 }
-}

src/binding/python/RecordComponent.cpp

@@ -374,7 +374,7 @@ struct PythonDynamicMemoryView
     {
     }
 
-    pybind11::memoryview currentView() const;
+    [[nodiscard]] pybind11::memoryview currentView() const;
 
     std::shared_ptr< void > m_dynamicView;
     ShapeContainer m_arrayShape;

src/helper/list_series.cpp

@@ -31,9 +31,7 @@
 #include <string>
 
 
-namespace openPMD
-{
-namespace helper
+namespace openPMD::helper
 {
     std::ostream &
     listSeries(
@@ -122,5 +120,4 @@ namespace helper
 
         return out;
     }
-} // helper
 } // openPMD

test/AuxiliaryTest.cpp

@@ -29,9 +29,7 @@
 using namespace openPMD;
 
 
-namespace openPMD
-{
-namespace test
+namespace openPMD::test
 {
 struct TestHelper : public Attributable
 {
@@ -40,7 +38,6 @@ struct TestHelper : public Attributable
         writable().IOHandler = createIOHandler(".", Access::CREATE, Format::JSON);
     }
 };
-} // test
 } // openPMD
 
 
@@ -142,17 +139,14 @@ TEST_CASE( "string_test", "[auxiliary]" )
     REQUIRE("1,2" == join({"1", "2"}, ","));
 }
 
-namespace openPMD
-{
-namespace test
+namespace openPMD::test
 {
 struct S : public TestHelper
 {
     S()
         : TestHelper()
     { }
 };
-} // test
 } // openPMD
 
 TEST_CASE( "container_default_test", "[auxiliary]")
@@ -168,9 +162,7 @@ TEST_CASE( "container_default_test", "[auxiliary]")
 #endif
 }
 
-namespace openPMD
-{
-namespace test
+namespace openPMD::test
 {
 struct structure : public TestHelper
 {
@@ -182,10 +174,9 @@ struct structure : public TestHelper
     int int_ = 42;
     float float_ = 3.14f;
 
-    std::string text() const { return std::get< std::string >(getAttribute("text").getResource()); }
+    [[nodiscard]] std::string text() const { return std::get< std::string >(getAttribute("text").getResource()); }
     structure& setText(std::string newText) { setAttribute("text", newText); return *this; }
 };
-} // test
 } // openPMD
 
 TEST_CASE( "container_retrieve_test", "[auxiliary]" )
@@ -247,9 +238,7 @@ TEST_CASE( "container_retrieve_test", "[auxiliary]" )
 #endif
 }
 
-namespace openPMD
-{
-namespace test
+namespace openPMD::test
 {
 struct Widget : public TestHelper
 {
@@ -261,7 +250,6 @@ struct Widget : public TestHelper
         : TestHelper()
     { }
 };
-} // test
 } // openPMD
 
 TEST_CASE( "container_access_test", "[auxiliary]" )
@@ -308,9 +296,7 @@ TEST_CASE( "attributable_default_test", "[auxiliary]" )
     REQUIRE(a.numAttributes() == 0);
 }
 
-namespace openPMD
-{
-namespace test
+namespace openPMD::test
 {
 struct AttributedWidget : public TestHelper
 {
@@ -323,7 +309,6 @@ struct AttributedWidget : public TestHelper
         return getAttribute(key).getResource();
     }
 };
-} // test
 } // openPMD
 
 TEST_CASE( "attributable_access_test", "[auxiliary]" )
@@ -356,9 +341,7 @@ TEST_CASE( "attributable_access_test", "[auxiliary]" )
     REQUIRE(a.numAttributes() == 1);
 }
 
-namespace openPMD
-{
-namespace test
+namespace openPMD::test
 {
 struct Dotty : public TestHelper
 {
@@ -370,14 +353,13 @@ struct Dotty : public TestHelper
         setAtt3("3");
     }
 
-    int att1() const { return std::get< int >(getAttribute("att1").getResource()); }
-    double att2() const { return std::get< double >(getAttribute("att2").getResource()); }
-    std::string att3() const { return std::get< std::string >(getAttribute("att3").getResource()); }
+    [[nodiscard]] int att1() const { return std::get< int >(getAttribute("att1").getResource()); }
+    [[nodiscard]] double att2() const { return std::get< double >(getAttribute("att2").getResource()); }
+    [[nodiscard]] std::string att3() const { return std::get< std::string >(getAttribute("att3").getResource()); }
     Dotty& setAtt1(int i) { setAttribute("att1", i); return *this; }
     Dotty& setAtt2(double d) { setAttribute("att2", d); return *this; }
     Dotty& setAtt3(std::string s) { setAttribute("att3", s); return *this; }
 };
-} // test
 } // openPMD
 
 TEST_CASE( "dot_test", "[auxiliary]" )

test/SerialIOTest.cpp

@@ -37,7 +37,7 @@ struct BackendSelection
     std::string backendName;
     std::string extension;
 
-    inline std::string jsonBaseConfig() const
+    [[nodiscard]] inline std::string jsonBaseConfig() const
     {
         return R"({"backend": ")" + backendName + "\"}";
     }