CMakeVersion: Add option to disable Git suffix

Distro maintainers who are building from Git with patches added on
may want to disable the automatic Git suffixing, as it does not
provide any useful information and simply confuses the end user.
Add an undocumented CMake_VERSION_NO_GIT variable to disable this.

1 files changed, 45 insertions, 43 deletions

diff --git a/Source/CMakeVersion.cmake b/Source/CMakeVersion.cmake
index 092f64d..9e785da 100644
--- a/Source/CMakeVersion.cmake
+++ b/Source/CMakeVersion.cmake
@@ -19,55 +19,57 @@ else()
   set(CMake_VERSION_IS_RELEASE 0)
 endif()
 
-# If this source was exported by 'git archive', use its commit info.
-set(git_info [==[$Format:%h %s$]==])
+if(NOT CMake_VERSION_NO_GIT)
+  # If this source was exported by 'git archive', use its commit info.
+  set(git_info [==[$Format:%h %s$]==])
 
-# Otherwise, try to identify the current development source version.
-if(NOT git_info MATCHES "^([0-9a-f][0-9a-f][0-9a-f][0-9a-f][0-9a-f][0-9a-f]?[0-9a-f]?)[0-9a-f]* "
-    AND EXISTS ${CMake_SOURCE_DIR}/.git)
-  find_package(Git QUIET)
-  if(GIT_FOUND)
-    macro(_git)
-      execute_process(
-        COMMAND ${GIT_EXECUTABLE} ${ARGN}
-        WORKING_DIRECTORY ${CMake_SOURCE_DIR}
-        RESULT_VARIABLE _git_res
-        OUTPUT_VARIABLE _git_out OUTPUT_STRIP_TRAILING_WHITESPACE
-        ERROR_VARIABLE _git_err ERROR_STRIP_TRAILING_WHITESPACE
-        )
-    endmacro()
-  endif()
-  if(COMMAND _git)
-    # Get the commit checked out in this work tree.
-    _git(log -n 1 HEAD "--pretty=format:%h %s" --)
-    set(git_info "${_git_out}")
+  # Otherwise, try to identify the current development source version.
+  if(NOT git_info MATCHES "^([0-9a-f][0-9a-f][0-9a-f][0-9a-f][0-9a-f][0-9a-f]?[0-9a-f]?)[0-9a-f]* "
+      AND EXISTS ${CMake_SOURCE_DIR}/.git)
+    find_package(Git QUIET)
+    if(GIT_FOUND)
+      macro(_git)
+        execute_process(
+          COMMAND ${GIT_EXECUTABLE} ${ARGN}
+          WORKING_DIRECTORY ${CMake_SOURCE_DIR}
+          RESULT_VARIABLE _git_res
+          OUTPUT_VARIABLE _git_out OUTPUT_STRIP_TRAILING_WHITESPACE
+          ERROR_VARIABLE _git_err ERROR_STRIP_TRAILING_WHITESPACE
+          )
+      endmacro()
+    endif()
+    if(COMMAND _git)
+      # Get the commit checked out in this work tree.
+      _git(log -n 1 HEAD "--pretty=format:%h %s" --)
+      set(git_info "${_git_out}")
+    endif()
   endif()
-endif()
 
-# Extract commit information if available.
-if(git_info MATCHES "^([0-9a-f][0-9a-f][0-9a-f][0-9a-f][0-9a-f][0-9a-f]?[0-9a-f]?)[0-9a-f]* (.*)$")
-  # Have commit information.
-  set(git_hash "${CMAKE_MATCH_1}")
-  set(git_subject "${CMAKE_MATCH_2}")
+  # Extract commit information if available.
+  if(git_info MATCHES "^([0-9a-f][0-9a-f][0-9a-f][0-9a-f][0-9a-f][0-9a-f]?[0-9a-f]?)[0-9a-f]* (.*)$")
+    # Have commit information.
+    set(git_hash "${CMAKE_MATCH_1}")
+    set(git_subject "${CMAKE_MATCH_2}")
 
-  # If this is not the exact commit of a release, add dev info.
-  if(NOT "${git_subject}" MATCHES "^[Cc][Mm]ake ${CMake_VERSION}$")
-    set(CMake_VERSION "${CMake_VERSION}-g${git_hash}")
-  endif()
+    # If this is not the exact commit of a release, add dev info.
+    if(NOT "${git_subject}" MATCHES "^[Cc][Mm]ake ${CMake_VERSION}$")
+      set(CMake_VERSION "${CMake_VERSION}-g${git_hash}")
+    endif()
 
-  # If this is a work tree, check whether it is dirty.
-  if(COMMAND _git)
-    _git(update-index -q --refresh)
-    _git(diff-index --name-only HEAD --)
-    if(_git_out)
-      set(CMake_VERSION_IS_DIRTY 1)
+    # If this is a work tree, check whether it is dirty.
+    if(COMMAND _git)
+      _git(update-index -q --refresh)
+      _git(diff-index --name-only HEAD --)
+      if(_git_out)
+        set(CMake_VERSION_IS_DIRTY 1)
+      endif()
+    endif()
+  else()
+    # No commit information.
+    if(NOT CMake_VERSION_IS_RELEASE)
+      # Generic development version.
+      set(CMake_VERSION "${CMake_VERSION}-git")
     endif()
-  endif()
-else()
-  # No commit information.
-  if(NOT CMake_VERSION_IS_RELEASE)
-    # Generic development version.
-    set(CMake_VERSION "${CMake_VERSION}-git")
   endif()
 endif()