Polish the code in setup.py.in

Change the PADDLE_VERSION in develop branch to latest

cmake/version.cmake

 # Get the latest git tag.
 set(PADDLE_VERSION $ENV{PADDLE_VERSION})
 set(tmp_version "HEAD")
+set(TAG_VERSION_REGEX "[0-9]+\\.[0-9]+\\.[0-9]+(\\.(a|b|rc)\\.[0-9]+)?")
+set(COMMIT_VERSION_REGEX "[0-9a-f]{5,40}")
 while ("${PADDLE_VERSION}" STREQUAL "")
   execute_process(
-    COMMAND ${GIT_EXECUTABLE} describe --tags --abbrev=0 ${tmp_version}
+    COMMAND ${GIT_EXECUTABLE} describe --tags --abbrev=0 --always ${tmp_version}
     WORKING_DIRECTORY ${PADDLE_SOURCE_DIR}
     OUTPUT_VARIABLE GIT_TAG_NAME
     RESULT_VARIABLE GIT_RESULT
     ERROR_QUIET OUTPUT_STRIP_TRAILING_WHITESPACE)
   if (NOT ${GIT_RESULT})
     # Check the tag is a correct version
-    if (${GIT_TAG_NAME} MATCHES "v[0-9]+\\.[0-9]+\\.[0-9]+(\\.(a|b|rc)\\.[0-9]+)?")
+    if (${GIT_TAG_NAME} MATCHES "${COMMIT_VERSION_REGEX}")
+      # if no tag was found, set PADDLE_VERSION to latest
+      set(PADDLE_VERSION "latest")
+    elseif (${GIT_TAG_NAME} MATCHES "v${VERSION_REGEX}")
       string(REPLACE "v" "" PADDLE_VERSION ${GIT_TAG_NAME})
     else()  # otherwise, get the previous git tag name.
       set(tmp_version "${GIT_TAG_NAME}~1")

python/setup.py.in

@@ -23,34 +23,22 @@ def _get_version_detail(idx):
     assert idx < 3, "vesion info consists of %(major)d.%(minor)d.%(patch)d, \
         so detail index must less than 3"
 
+    if re.match('@TAG_VERSION_REGEX@', '@PADDLE_VERSION@'):
         version_details = '@PADDLE_VERSION@'.split('.')
+
         if len(version_details) == 3:
-        detail = version_details[idx]
-        if re.match('[0-9]+', detail):
-            return int(detail)
+            return version_details[idx]
 
-    return None
+    return 'UNKNOWN'
 
 def get_major():
-    major = _get_version_detail(0)
-    if major is not None:
-        return major
-
-    return 'UNKNOWN'
+    return _get_version_detail(0)
 
 def get_minor():
-    minor = _get_version_detail(1)
-    if minor is not None:
-        return minor
-
-    return 'UNKNOWN'
+    return _get_version_detail(1)
 
 def get_patch():
-    patch = _get_version_detail(2)
-    if patch is not None:
-        return patch
-
-    return 'UNKNOWN'
+    return _get_version_detail(2)
 
 def is_taged():
     try: