(#18) Added function to return the version string

Added a VERSION_STRING() function that gives the version string in
the standard format.

src/papi/lz4/api.h

@@ -2,6 +2,7 @@
 #define __CINT_LZ4_API__
 #pragma once
 
+#include <string>
 #include <gsl/gsl>
 #include "module.h"
 #include "api_detail.h"
@@ -35,6 +36,11 @@ namespace lz4 { namespace api {
             return _detail::VERSION_RELEASE;
         };        
 
+    constexpr auto VERSION_STRING() 
+        {
+            return _detail::VERSION_STRING;
+        };
+
     /**
         Provides the maximum size that LZ4 compression may output in a "worst case" scenario (input data not compressible)
         This function is primarily useful for memory allocation purposes (destination buffer size).

src/papi/lz4/api_detail.h

@@ -14,6 +14,7 @@ namespace lz4 { namespace api {
             constexpr auto VERSION_MAJOR = LZ4_VERSION_MAJOR;
             constexpr auto VERSION_MINOR = LZ4_VERSION_MINOR;
             constexpr auto VERSION_RELEASE = LZ4_VERSION_RELEASE;
+            constexpr const char VERSION_STRING[] = LZ4_VERSION_STRING; 
 
             template<int Size>
                 constexpr auto COMPRESSBOUND = LZ4_COMPRESSBOUND(Size);

src/papi/lz4/init.cpp

@@ -10,5 +10,9 @@ static test_initializer modules([](py::module &m) {
         .def("versionNumber", lz4::api::VERSION_NUMBER)
         .def("version", [](){
             return py::make_tuple(lz4::api::VERSION_MAJOR(), lz4::api::VERSION_MINOR(), lz4::api::VERSION_RELEASE());
-        });
+        })
+        .def("versionString", [](){
+            return py::str(lz4::api::VERSION_STRING());
+        })
+    ;
 });

tests/papi/test_lz4.py

@@ -9,3 +9,4 @@ def lz4():
 def testVersion(lz4):
     assert lz4.versionNumber() == 10702
     assert lz4.version() == (1, 7, 2)
+    assert lz4.versionString() == "1.7.2"