Only retain the sed change if it is needed

Author: ocaisa

install_scripts.sh

@@ -37,6 +37,30 @@ file_changed_in_pr() {
   ) && return 0 || return 1
 }
 
+sed_update_if_changed() {
+    # Usage: sed_update_if_changed 's/foo/bar/' file.txt
+    if [ "$#" -ne 2 ]; then
+        echo "Usage: sed_update_if_changed 'sed_command' file" >&2
+        return 1
+    fi
+
+    local sed_command="$1"
+    local file="$2"
+    local tmp_file="$(mktemp "${file}.XXXXXX")"
+
+    sed "$sed_command" "$file" > "$tmp_file" || {
+        rm -f "$tmp_file"
+        echo "sed command failed" >&2
+        return 1
+    }
+
+    if ! cmp -s "$file" "$tmp_file"; then
+        mv "$tmp_file" "$file"
+    else
+        rm -f "$tmp_file"
+    fi
+}
+
 compare_and_copy() {
     if [ "$#" -ne 2 ]; then
         echo "Usage of function: compare_and_copy <source_file> <destination_file>"
@@ -134,8 +158,6 @@ init_files=(
     minimal_eessi_env README.md test.py lmod_eessi_archdetect_wrapper.sh lmod_eessi_archdetect_wrapper_accel.sh
 
 )
-# make sure that scripts in init/ and scripts/ use correct EESSI version
-sed -i "s/__EESSI_VERSION_DEFAULT__/${EESSI_VERSION}/g" ${TOPDIR}/init/eessi_defaults
 copy_files_by_list ${TOPDIR}/init ${INSTALL_PREFIX}/init "${init_files[@]}"
 
 # Copy for the init/arch_specs directory
@@ -154,16 +176,12 @@ copy_files_by_list ${TOPDIR}/init/Magic_Castle ${INSTALL_PREFIX}/init/Magic_Cast
 mc_files=(
    2023.06.lua
 )
-# replace EESSI version used in comments in EESSI module
-sed -i "s@/<EESSI_VERSION>/@/${EESSI_VERSION}/@g" ${TOPDIR}/init/modules/EESSI/${EESSI_VERSION}.lua
 copy_files_by_list ${TOPDIR}/init/modules/EESSI ${INSTALL_PREFIX}/init/modules/EESSI "${mc_files[@]}"
 
 # Copy for init/lmod directory
-init_script_files=$(ls ${TOPDIR}/init/lmod)
-# replace placeholder for default EESSI version in Lmod init scripts
-for shell in $init_script_files; do
-    sed -i "s/__EESSI_VERSION_DEFAULT__/${EESSI_VERSION}/g" ${TOPDIR}/init/lmod/${shell}
-done
+init_script_files=(
+    bash zsh ksh fish csh    
+)
 copy_files_by_list ${TOPDIR}/init/lmod ${INSTALL_PREFIX}/init/lmod "${init_script_files[@]}"
 
 # Copy for the scripts directory
@@ -192,6 +210,22 @@ ${INSTALL_PREFIX}/scripts/gpu_support/nvidia/easystacks "${host_injections_easys
 hook_files=(
     eb_hooks.py
 )
-# replace EESSI version used in EasyBuild hooks
-sed -i "s@/eessi-<EESSI_VERSION>/@/eessi-${EESSI_VERSION}/@g" ${TOPDIR}/eb_hooks.py
 copy_files_by_list ${TOPDIR} ${INSTALL_PREFIX}/init/easybuild "${hook_files[@]}"
+
+# replace version placeholders in scripts;
+# note: the commands below are always run, regardless of whether the scripts were changed,
+# but that should be fine (no changes are made if version placeholder is not present anymore)
+
+# make sure that scripts in init/ and scripts/ use correct EESSI version
+sed_update_if_changed "s/__EESSI_VERSION_DEFAULT__/${EESSI_VERSION}/g" ${INSTALL_PREFIX}/init/eessi_defaults
+
+# replace placeholder for default EESSI version in Lmod init scripts
+for shell in $(ls ${INSTALL_PREFIX}/init/lmod); do
+    sed_update_if_changed "s/__EESSI_VERSION_DEFAULT__/${EESSI_VERSION}/g" ${INSTALL_PREFIX}/init/lmod/${shell}
+done
+
+# replace EESSI version used in comments in EESSI module
+sed_update_if_changed "s@/<EESSI_VERSION>/@/${EESSI_VERSION}/@g" ${INSTALL_PREFIX}/init/modules/EESSI/${EESSI_VERSION}.lua
+
+# replace EESSI version used in EasyBuild hooks
+sed_update_if_changed "s@/<EESSI_VERSION>/@/${EESSI_VERSION}/@g" ${INSTALL_PREFIX}/init/easybuild/eb_hooks.py