fix(terragrunt_* hooks): Use new subcommands for terragrunt v0.78.0+ instead of deprecated ones

hooks/_common.sh

@@ -606,3 +606,36 @@ function common::export_provided_env_vars {
     export $var_name="$var_value"
   done
 }
+
+#######################################################################
+# Check if the installed Terragrunt version is >=0.78.0 or not
+#
+# This function help to determine which terragrunt subcomand to use
+# based on Terragrunt version
+#
+# Returns:
+#   - 0 if version >= 0.78.0
+#   - 1 if version < 0.78.0
+#    Defaults to 0 if version cannot be determined
+#######################################################################
+# TODO: Drop after May 2027. Two years to upgrade is more than enough.
+function common::terragrunt_version_above_0.78 {
+  local terragrunt_version
+
+  # Extract version number (e.g., "terragrunt version v0.80.4" -> "0.80")
+  terragrunt_version=$(terragrunt --version 2> /dev/null | grep -oE '[0-9]+\.[0-9]+')
+  # If we can't parse version, default to newer command
+  if [[ -z "$terragrunt_version" ]]; then
+    return 0
+  fi
+
+  local major minor
+  IFS='.' read -r major minor <<< "$terragrunt_version"
+
+  # `hcl format` support added in v0.78.0 (May 2025)
+  if [[ $major -gt 0 ]] || [[ $major -eq 0 && $minor -ge 78 ]]; then
+    return 0
+  else
+    return 1
+  fi
+}

hooks/terragrunt_fmt.sh

@@ -12,7 +12,13 @@ function main {
   common::parse_cmdline "$@"
   common::export_provided_env_vars "${ENV_VARS[@]}"
   common::parse_and_export_env_vars
-  # JFYI: terragrunt hclfmt color already suppressed via PRE_COMMIT_COLOR=never
+  # JFYI: `terragrunt hcl format` color already suppressed via PRE_COMMIT_COLOR=never
+
+  if common::terragrunt_version_above_0.78; then
+    readonly SUBCOMMAND="hcl format"
+  else
+    readonly SUBCOMMAND="hclfmt"
+  fi
 
   # shellcheck disable=SC2153 # False positive
   common::per_dir_hook "$HOOK_ID" "${#ARGS[@]}" "${ARGS[@]}" "${FILES[@]}"
@@ -46,7 +52,7 @@ function per_dir_hook_unique_part {
   local -a -r args=("$@")
 
   # pass the arguments to hook
-  terragrunt hclfmt "${args[@]}"
+  terragrunt "$SUBCOMMAND" "${args[@]}"
 
   # return exit code to common::per_dir_hook
   local exit_code=$?
@@ -63,7 +69,7 @@ function run_hook_on_whole_repo {
   local -a -r args=("$@")
 
   # pass the arguments to hook
-  terragrunt hclfmt "$(pwd)" "${args[@]}"
+  terragrunt "$SUBCOMMAND" "$(pwd)" "${args[@]}"
 
   # return exit code to common::per_dir_hook
   local exit_code=$?