From 681daf84e742271d464009740a87f8ddbd3646ba Mon Sep 17 00:00:00 2001
From: Koichi Murase <myoga.murase@gmail.com>
Date: Sun, 9 Apr 2023 23:13:02 +0900
Subject: [PATCH] lib/util: Add "_omb_util_alias_delayed"

---
 aliases/general.aliases.sh | 67 +++++++++++++++++++-------------------
 lib/utils.sh               | 24 ++++++++++++++
 2 files changed, 58 insertions(+), 33 deletions(-)

diff --git a/aliases/general.aliases.sh b/aliases/general.aliases.sh
index 1e97dcf..3cd9670 100644
--- a/aliases/general.aliases.sh
+++ b/aliases/general.aliases.sh
@@ -21,45 +21,46 @@
 #   1.  MAKE TERMINAL BETTER
 #   -----------------------------
 
-# Determines the use of the option `-v' on the first call
-# Ref. https://github.com/ohmybash/oh-my-bash/issues/351
-function _omb_alias_general_cp_init {
+# Preferred 'cp' implementation.  Determines the use of the option `-v' on the
+# first call Ref. https://github.com/ohmybash/oh-my-bash/issues/351
+function _omb_util_alias_select_cp {
   if (tmp=$(_omb_util_mktemp); trap 'rm -f "$tmp"{,.2}' EXIT; command cp -v "$tmp" "$tmp.2" &>/dev/null); then
-    alias cp='cp -iv' && function _omb_alias_general_cp_init { command cp -iv "$@"; }
+    _omb_command='cp -iv'
   else
-    alias cp='cp -i' && function _omb_alias_general_cp_init { command cp -i "$@"; }
-  fi &&
-    _omb_alias_general_cp_init "$@"
+    _omb_command='cp -i'
+  fi
 }
-function _omb_alias_general_mv_init {
-  if (tmp=$(_omb_util_mktemp); trap 'rm -f "$tmp.2"' EXIT; command mv -v "$tmp" "$tmp.2" &>/dev/null); then
-    alias mv='mv -iv' && function _omb_alias_general_mv_init { command mv -iv "$@"; }
-  else
-    alias mv='mv -i' && function _omb_alias_general_mv_init { command mv -i "$@"; }
-  fi &&
-    _omb_alias_general_mv_init "$@"
-}
-function _omb_alias_general_mkdir_init {
-  if command mkdir -pv . &>/dev/null; then
-    alias mkdir='mkdir -pv' && function _omb_alias_general_mkdir_init { command mkdir -pv "$@"; }
-  else
-    alias mkdir='mkdir -p' && function _omb_alias_general_mkdir_init { command mkdir -p "$@"; }
-  fi &&
-    _omb_alias_general_mkdir_init "$@"
-}
-alias cp='_omb_alias_general_cp_init'       # Preferred 'cp' implementation
-alias mv='_omb_alias_general_mv_init'       # Preferred 'mv' implementation
-alias mkdir='_omb_alias_general_mkdir_init' # Preferred 'mkdir' implementation
+_omb_util_alias_delayed cp force
 
-function _omb_alias_general_nano_init {
-  if LANG=C command nano --help 2>/dev/null | grep -q '^[[:space:]]*[-]W'; then
-    alias nano='nano -W' && function _omb_alias_general_nano_init { command nano -W "$@"; }
+# Preferred 'mv' implementation
+function _omb_util_alias_select_mv {
+  if (tmp=$(_omb_util_mktemp); trap 'rm -f "$tmp.2"' EXIT; command mv -v "$tmp" "$tmp.2" &>/dev/null); then
+    _omb_command='mv -iv'
   else
-    unalias nano 2>/dev/null; function _omb_alias_general_nano_init { command nano "$@"; }
-  fi &&
-    _omb_alias_general_nano_init "$@"
+    _omb_command='mv -i'
+  fi
 }
-alias nano='_omb_alias_general_nano_init'   # Preferred 'nano' implementation
+_omb_util_alias_delayed mv force
+
+# Preferred 'mkdir' implementation
+function _omb_util_alias_select_mkdir {
+  if command mkdir -pv . &>/dev/null; then
+    _omb_command='mkdir -pv'
+  else
+    _omb_command='mkdir -p'
+  fi
+}
+_omb_util_alias_delayed mkdir force
+
+# Preferred 'nano' implementation
+function _omb_util_alias_select_nano {
+  if LANG=C command nano --help 2>/dev/null | grep -q '^[[:space:]]*[-]W'; then
+    _omb_command='nano -W'
+  else
+    _omb_command='nano'
+  fi
+}
+_omb_util_alias_delayed nano force
 
 alias ll='ls -lAFh'                         # Preferred 'ls' implementation
 alias less='less -FSRXc'                    # Preferred 'less' implementation
diff --git a/lib/utils.sh b/lib/utils.sh
index 049c44f..0504758 100644
--- a/lib/utils.sh
+++ b/lib/utils.sh
@@ -402,6 +402,30 @@ function _omb_util_alias {
   alias -- "$1"
 }
 
+function _omb_util_alias_delayed__init {
+  local _omb_name=$1 _omb_init=${FUNCNAME[1]}
+  local _omb_command=$_omb_name
+  "_omb_util_alias_select_$_omb_name"
+
+  if [[ ! $_omb_command || $_omb_command == "$_omb_name" ]]; then
+    unalias "$_omb_name"
+  else
+    alias "$_omb_name=$_omb_command"
+  fi || return 1
+
+  eval -- "function $_omb_init { command ${_omb_command:-$_omb_name} \"\$@\"; }" && "$_omb_init" "${@:2}"
+}
+function _omb_util_alias_delayed {
+  local name=$1 opts=${2-}
+  local func=_omb_util_alias_init_$name
+  eval -- "function $func { _omb_util_alias_delayed__init $name \"\$@\"; }"
+  if [[ :$opts: == *:force:* ]]; then
+    alias "$name=$func"
+  else
+    _omb_util_alias "$name=$func"
+  fi
+}
+
 function _omb_util_mktemp {
   local template=tmp.oh-my-bash.XXXXXXXXXX
   if _omb_util_command_exists mktemp; then