Convert libdiffpy_version_info to namedtuple.

- add micro and patch fields to libdiffpy_version_info
- require libdiffpy >= 1.3 to ensure libdiffpy_version_info is
  available at runtime.
- deprecate get_libdiffpy_version_info

Author: pavoljuhas

diffpy/srreal/version.py

@@ -14,7 +14,7 @@
 ##############################################################################
 
 
-"""Definition of __version__, __date__, __gitsha__.
+"""Definition of __version__, __date__, __gitsha__, libdiffpy_version_info.
 """
 
 from pkg_resources import resource_filename
@@ -33,42 +33,42 @@
 
 del cp
 
-# Access to version data of the libdiffpy shared library ---------------------
+# version information on the active libdiffpy shared library -----------------
 
-def get_libdiffpy_version_info():
-    """Get version data for the linked libdiffpy shared library.
-
-    Return a singleton instance of libdiffpy_version_info class.
-    """
-    global _lvi
-    if _lvi is not None:  return _lvi
-    from diffpy.srreal.srreal_ext import _get_libdiffpy_version_info_dict
-    vd = _get_libdiffpy_version_info_dict()
-
-    class libdiffpy_version_info(object):
+from collections import namedtuple
+from diffpy.srreal.srreal_ext import _get_libdiffpy_version_info_dict
 
-        """Version information for the loaded libdiffpy shared library.
+libdiffpy_version_info = namedtuple('libdiffpy_version_info',
+        "version version_number major minor micro patch date git_sha")
+vd = _get_libdiffpy_version_info_dict()
+libdiffpy_version_info = libdiffpy_version_info(
+        version = vd['version_str'],
+        version_number = vd['version'],
+        major = vd['major'],
+        minor = vd['minor'],
+        micro = vd['micro'],
+        patch = vd['patch'],
+        date = vd['date'],
+        git_sha = vd['git_sha'])
+del vd
 
-        version  -- version string for the loaded libdiffpy library.
-        version_number -- Integer encoding of the library version.
-        major    -- Major version number of the library.
-        minor    -- Minor version number of the library.
-        date     -- Git commit date of the libdiffpy sources.
-        git_sha  -- Git commit hash of this libdiffpy version.
-        """
 
-        version = vd['version_str']
-        version_number = vd['version']
-        major = vd['major']
-        minor = vd['minor']
-        date = vd['date']
-        git_sha = vd['git_sha']
+def get_libdiffpy_version_info():
+    """
+    Get version data for the active libdiffpy shared library.
 
-    # class libdiffpy_version_info
+    Returns
+    -------
+    libdiffpy_version_info
+        a namedtuple which contains libdiffpy version data.
 
-    _lvi = libdiffpy_version_info()
-    return get_libdiffpy_version_info()
 
-_lvi = None
+    .. note:: Deprecated in diffpy.srreal 1.1
+          `libdiffpy_version_info` will be removed in diffpy.srreal 1.2.
+    """
+    from warnings import warn
+    warn("get_libdiffpy_version_info is deprecated, "
+         "use the libdiffpy_version_info object.", DeprecationWarning)
+    return libdiffpy_version_info
 
 # End of file

srrealmodule/wrap_libdiffpy_version.cpp

@@ -20,6 +20,10 @@
 #include <boost/python/dict.hpp>
 #include <boost/python/def.hpp>
 
+#if DIFFPY_VERSION < 1003000
+#error "diffpy.srreal requires libdiffpy 1.3 or later."
+#endif
+
 namespace srrealmodule {
 namespace nswrap_libdiffpy_version {
 
@@ -36,22 +40,18 @@ Return dictionary with version data for the loaded libdiffpy library.\n\
 python::dict get_libdiffpy_version_info_dict()
 {
     python::dict rv;
-#if DIFFPY_VERSION > 1002048
     // Obtain version data from runtime values.
     rv["version"] = libdiffpy_version_info::version;
     rv["version_str"] = libdiffpy_version_info::version_str;
     rv["major"] = libdiffpy_version_info::major;
     rv["minor"] = libdiffpy_version_info::minor;
+    rv["micro"] = libdiffpy_version_info::micro;
     rv["date"] = libdiffpy_version_info::date;
     rv["git_sha"] = libdiffpy_version_info::git_sha;
+#if DIFFPY_VERSION > 1003000
+    rv["patch"] = libdiffpy_version_info::patch;
 #else
-    // For old libdiffpy revert to compile time values.
-    rv["version"] = DIFFPY_VERSION;
-    rv["version_str"] = DIFFPY_VERSION_STR;
-    rv["major"] = DIFFPY_VERSION_MAJOR;
-    rv["minor"] = DIFFPY_VERSION_MINOR;
-    rv["date"] = DIFFPY_VERSION_DATE;
-    rv["git_sha"] = DIFFPY_GIT_SHA;
+    rv["patch"] = 0;
 #endif
     return rv;
 }