From 1cb6e413258d7f382447ff73e832101271d7f0b4 Mon Sep 17 00:00:00 2001
From: program-- <justin@justinsingh.me>
Date: Thu, 22 Aug 2024 07:32:10 -0700
Subject: [PATCH] feat(cmake): include git commit id in configuration summary

---
 CMakeLists.txt                  | 6 +++++-
 cmake/GitUpdateSubmodules.cmake | 7 +++++++
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 22a3af6b41..f4756bdfd2 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -31,6 +31,7 @@ list(APPEND CMAKE_MODULE_PATH "${NGEN_MOD_DIR}")
 #   (1) finds Git package
 #   (2) Sets ${NGEN_HAS_GIT_DIR} to ON/OFF if ${NGEN_ROOT_DIR}/.git exists
 #   (3) Function `git_update_submodule` which updates a given submodule
+#   (4) Sets ${NGEN_GIT_COMMIT} to the current commit hash if available
 include(GitUpdateSubmodules)
 
 # NGen CMake module for automating external subdirectory builds (i.e. testbmicpp)
@@ -406,7 +407,10 @@ ngen_multiline_message(
 "  C Compiler: ${CMAKE_C_COMPILER}"
 "  C Flags: ${CMAKE_C_FLAGS}"
 "  CXX Compiler: ${CMAKE_CXX_COMPILER}"
-"  CXX Flags: ${CMAKE_CXX_FLAGS}"
+"  CXX Flags: ${CMAKE_CXX_FLAGS}")
+ngen_dependent_multiline_message(NGEN_HAS_GIT_DIR
+"  Git Commit ID: ${NGEN_GIT_COMMIT}")
+ngen_multiline_message(
 "  Flags:"
 "    NGEN_WITH_MPI: ${NGEN_WITH_MPI}"
 "    NGEN_WITH_NETCDF: ${NGEN_WITH_NETCDF}"
diff --git a/cmake/GitUpdateSubmodules.cmake b/cmake/GitUpdateSubmodules.cmake
index 366f325116..140d045499 100644
--- a/cmake/GitUpdateSubmodules.cmake
+++ b/cmake/GitUpdateSubmodules.cmake
@@ -2,6 +2,13 @@ find_package(Git QUIET)
 
 if(EXISTS "${NGEN_ROOT_DIR}/.git")
     set(NGEN_HAS_GIT_DIR ON)
+
+    execute_process(
+        COMMAND ${GIT_EXECUTABLE} rev-parse HEAD
+        WORKING_DIRECTORY ${NGEN_ROOT_DIR}
+        OUTPUT_VARIABLE NGEN_GIT_COMMIT
+        OUTPUT_STRIP_TRAILING_WHITESPACE
+    )
 else()
     set(NGEN_HAS_GIT_DIR OFF)
 endif()