CMakeVersion: Prefer Git information provided by 'git archive' exports
Update the approach from commit fe2c558ba6 (CMakeVersion: Preserve Git
information during 'git archive', 2019-07-25, v3.16.0-rc1~337^2) to
prefer `export-subst` information. This will allow exported source
trees to be imported into unrelated Git repositories while still using
the original upstream CMake commit information.
diff --git a/Source/CMakeVersion.cmake b/Source/CMakeVersion.cmake
index 0f2a2d2..092f64d 100644
--- a/Source/CMakeVersion.cmake
+++ b/Source/CMakeVersion.cmake
@@ -19,7 +19,12 @@
set(CMake_VERSION_IS_RELEASE 0)
endif()
-if(EXISTS ${CMake_SOURCE_DIR}/.git)
+# If this source was exported by 'git archive', use its commit info.
+set(git_info [==[$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 ${CMake_SOURCE_DIR}/.git)
find_package(Git QUIET)
if(GIT_FOUND)
macro(_git)
@@ -32,16 +37,11 @@
)
endmacro()
endif()
-endif()
-
-# Try to identify the current development source version.
-if(COMMAND _git)
- # Get the commit checked out in this work tree.
- _git(log -n 1 HEAD "--pretty=format:%h %s" --)
- set(git_info "${_git_out}")
-else()
- # Get the commit exported by 'git archive'.
- set(git_info [==[$Format:%h %s$]==])
+ 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()
# Extract commit information if available.
