edit: support "nsearch" opts "empty=emulate-readline"

README.md

@@ -104,7 +104,7 @@ Of course ble.sh can be used in combination with other Bash configurations such
 ## History and roadmap
 
 My little experiment has took place in one corner of my `bashrc` in the end of May, 2013 after I enjoyed some article on `zsh-syntax-highlighting`.
-I initially thought something can be achieved by writing a few hundred of codes
+I initially thought something can be achieved by writing a few hundred of lines of codes
 but soon realized that everything needs to be re-implemented for the authentic support of syntax highlighting in Bash.
 I decided to make it as an independent script `ble.sh`.
 The name stemmed from that of Zsh's line editor, *ZLE* (*Zsh Line Editor*), but suffixed with `.sh` for the implication of being written in shell script.

docs/ChangeLog.md

@@ -27,6 +27,7 @@
 - syntax: support tilde expansions in parameter expansions `#D1513` 0506df2
 - decode: support `ble-bind -m KEYMAP --cursor DECSCUSR` (motivated by jmederosalvarado) `#D1514` `#D1515` `#D1516` 79d671d
 - edit: support `nsearch` options (motivated by Alyetama, rashil2000, carv-silva) `#D1517` 9125795
+  - edit: support `nsearch` opts `empty=emulate-readline` (motivated by jainpratik163) `#D1661` 0000000
 - syntax: support the deprecated redirection `>& file` `#D1539` b9b0de4
 - complete: complete file descriptors and heredoc words after redirections `#D1539` b9b0de4
 - main: support `blehook ATTACH DETACH`, `BLE_ONLOAD`, `BLE_ATTACHED` `#D1543` 750ca38

lib/core-decode.emacs-rlfunc.txt

@@ -55,8 +55,8 @@ glob-expand-word                  complete context=glob:insert-all
 glob-list-expansions              complete context=glob:show_menu
 history-and-alias-expand-line     history-and-alias-expand-line
 history-expand-line               history-expand-line
-history-search-backward           history-search-backward empty=history-move
-history-search-forward            history-search-forward empty=history-move
+history-search-backward           history-search-backward empty=emulate-readline
+history-search-forward            history-search-forward empty=emulate-readline
 history-substring-search-backward history-substring-search-backward
 history-substring-search-forward  history-substring-search-forward
 insert-comment                    insert-comment

lib/core-decode.vi_imap-rlfunc.txt

@@ -55,8 +55,8 @@ glob-expand-word                  complete context=glob:insert-all
 glob-list-expansions              complete context=glob:show_menu
 history-and-alias-expand-line     history-and-alias-expand-line
 history-expand-line               history-expand-line
-history-search-backward           history-search-backward empty=history-move
-history-search-forward            history-search-forward empty=history-move
+history-search-backward           history-search-backward empty=emulate-readline
+history-search-forward            history-search-forward empty=emulate-readline
 history-substring-search-backward history-substring-search-backward
 history-substring-search-forward  history-substring-search-forward
 insert-comment                    insert-comment

lib/core-decode.vi_nmap-rlfunc.txt

@@ -55,8 +55,8 @@ glob-expand-word                  -
 glob-list-expansions              -
 history-and-alias-expand-line     vi_nmap/@edit history-and-alias-expand-line
 history-expand-line               vi_nmap/@edit history-expand-line
-history-search-backward           history-search-backward empty=history-move
-history-search-forward            history-search-forward empty=history-move
+history-search-backward           history-search-backward empty=emulate-readline
+history-search-forward            history-search-forward empty=emulate-readline
 history-substring-search-backward history-substring-search-backward
 history-substring-search-forward  history-substring-search-forward
 insert-comment                    vi-rlfunc/insert-comment

note.txt

@@ -2479,9 +2479,14 @@ bash_tips
 
 2021-05-03
 
+  * rlfunc: fetch-history
+    8f485ff8 - new readline "fetch-history" bindable command
   * rlfunc: C-x s, spell-correct-word
+    6be3a741
   * rlvar: enable-active-region
+    b1965836 new "enable-active-region" readline variable
   * rlbind: prior, next
+    65822e50 - alias expansion fix in case statements
   * vi-undo
 
   * 5.2 新機能: READLINE_ARGUMENT: 調べてみると引数が存在している時にのみ定義さ
@@ -5423,6 +5428,25 @@ bash_tips
     Done (実装ログ)
 -------------------------------------------------------------------------------
 
+2021-09-23
+
+  * edit (widget history-search): support empty=emulate-readline (motivated by jainpratik163) [#D1661]
+    https://github.com/akinomyoga/ble.sh/issues/139
+
+    history-search-{for,back}ward は検索なので一致場所にカーソルを置くという仕
+    様に今までしてきた。また、空文字列検索の時には空文字列による検索を継続する
+    為に、敢えてカーソルを先頭に置く様にしていた。しかし、readline の振る舞いを
+    改めて確認した所、空文字列の時には恰も通常の history-prev を使用して移動し
+    たかの様に振る舞っていながら、空文字検索を継続しているのだという事が判明し
+    た。仕方がないので ble.sh でもやはり空文字列検索であっても内部的には
+    nsearch 状態に突入して、但しカーソル位置は末尾にするという具合に変更する事
+    にした。
+
+    改めて思うに Ref #D1517 https://github.com/akinomyoga/ble.sh/issues/101 で
+    要望にあった"2. I would like the cursor to move to the end of line while
+    searching with Up/Down." というのはこの振る舞いに関連しての事だったのではな
+    いかという気がする。まあ、今となっては考えても仕方のない事なのかもしれない。
+
 2021-09-22
 
   * README: roadmap [#D1660]

src/edit.sh

@@ -7222,11 +7222,13 @@ function ble-edit/nsearch/.goto-match {
   _ble_edit_nsearch_index=$index
   _ble_edit_mark=$beg
   local is_end_marker=
-  case :$opts: in
-  (*:point=begin:*)       _ble_edit_ind=0 ;;
-  (*:point=end:*)         _ble_edit_ind=${#_ble_edit_str} is_end_marker=1 ;;
-  (*:point=match-begin:*) _ble_edit_ind=$beg ;;
-  (*:point=match-end:*|*) _ble_edit_ind=$end is_end_marker=1 ;;
+  local rex=':point=([^:]*):'
+  [[ :$opts: =~ $rex ]]
+  case ${BASH_REMATCH[1]} in
+  (begin)       _ble_edit_ind=0 ;;
+  (end)         _ble_edit_ind=${#_ble_edit_str} is_end_marker=1 ;;
+  (match-begin) _ble_edit_ind=$beg ;;
+  (match-end|*) _ble_edit_ind=$end is_end_marker=1 ;;
   esac
 
   # vi_nmap の中にいる時は一致範囲の最後の文字にカーソルを置く
@@ -7364,10 +7366,11 @@ function ble-edit/nsearch/backward.fib {
 ##
 ##     empty=EMPTY
 ##       空文字列で検索を開始した時の動作を指定します。
-##       previous-search 前回の検索文字列を使用して検索します [既定]
-##       empty-search    空文字列で検索します。
-##       hide-status     空文字列検索。nsearch 状態は隠します。
-##       history-move    履歴項目移動。コマンドライン先頭に移動します。
+##       previous-search  前回の検索文字列を使用して検索します [既定]
+##       empty-search     空文字列で検索します。
+##       hide-status      空文字列検索。nsearch 状態は隠します。
+##       history-move     履歴項目移動。コマンドライン先頭に移動します。
+##       emulate-readline Readline の動作を模倣します。hide-status 及び point=end を設定します。
 ##
 ##     action=ACTION
 ##       文字列が見つかった時の動作を指定します。
@@ -7420,6 +7423,8 @@ function ble/widget/history-search {
       return $? ;;
     (hide-status)
       opts=$opts:hide-status ;;
+    (emulate-readline)
+      opts=hide-status:point=end:$opts ;;
     (previous-search)
       _ble_edit_nsearch_needle=$_ble_edit_nsearch_prev ;;
     esac