Improve release target

Author: eel76-hmi

CMakeLists.txt

@@ -55,10 +55,14 @@ add_custom_target(package DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/${PACKAGE_NAME}")
 # create a release (by pushing a tag to the repository)
 
 find_program(GIT git REQUIRED)
+find_program(GREP grep REQUIRED)
 
 add_custom_target(
   release
   WORKING_DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}"
+  COMMAND "${GIT}" diff-index --quiet HEAD -- # check for uncommitted changes
+  COMMAND "${GIT}" branch --show-current | "${GREP}" -qx main # check for main branch
+  COMMAND "${GIT}" cherry -v origin/main | "${GREP}" grep -q '^' # check for unpushed commits
   COMMAND "${GIT}" tag "v${CMAKE_PROJECT_VERSION}"
   COMMAND "${GIT}" push "v${CMAKE_PROJECT_VERSION}")