common: Configuration for VS Code shell integration

NEWS

@@ -1,4 +1,4 @@
-History of Yash
+# History of Yash
 
 ## Yash 2.57 (Unreleased)
 
@@ -13,6 +13,8 @@ History of Yash
   - [line-editing] Completion no longer inserts a redundant backslash
     to escape a character included in the completed word
     when the cursor follows another backslash.
+  - Updated the sample initialization script (yashrc):
+    - Added setup for VS Code shell integration.
 
 ## Yash 2.56.1 (2024-03-20)
 

NEWS.ja

@@ -1,4 +1,4 @@
-Yash 更新履歴
+# Yash 更新履歴
 
 ## Yash 2.57 (未リリース)
 
@@ -12,6 +12,8 @@ Yash 更新履歴
   - [行編集] カーソルがバックスラッシュの直後にある時に補完をすると
     補完する単語に含まれるエスケープが必要な文字に対して
     余計なバックスラッシュが挿入されるのを修正
+  - 初期化スクリプト (yashrc) のサンプルを更新:
+    - VS Code シェル統合のための設定を追加
 
 ## Yash 2.56.1 (2024-03-20)
 

share/initialization/common

@@ -268,6 +268,48 @@ if [ "$_tsl" ] && [ "$_fsl" ]; then
 
 fi
 
+# support VS Code shell integration
+if [ "${TERM_PROGRAM-}" = vscode ]; then
+
+  # wrap the prompt with markers
+  YASH_PS1="\[\e]633;A\e\\\\\]$YASH_PS1\[\e]633;B\e\\\\\]"
+  YASH_PS1R="\[\e]633;A\e\\\\\]$YASH_PS1R\[\e]633;B\e\\\\\]"
+  YASH_PS2="\[\e]633;A\e\\\\\]$YASH_PS2\[\e]633;B\e\\\\\]"
+
+  # notify the terminal before executing a command
+  _send_cmdline() {
+    # Following the pre-execution mark, we also print the command line content
+    # so the terminal can receive the correct command especially in the presence
+    # of the right prompt. Some characters need to be escaped, so we print them
+    # one by one.
+    printf '\033]633;C\033\\\033]633;E;'
+    typeset cmd="$COMMAND"
+    while [ "$cmd" ]; do
+      case "${cmd[1]}" in
+        (';'|[
-' '])
+          printf '\\x%.2X' "'${cmd[1]}"
+          ;;
+        (\\)
+          printf '\\\\'
+          ;;
+        (*)
+          printf %c "${cmd[1]}"
+          ;;
+      esac
+      cmd=${cmd[2,-1]}
+    done
+    printf '\033\\'
+  }
+  POST_PROMPT_COMMAND=("$POST_PROMPT_COMMAND" _send_cmdline)
+
+  # notify the terminal after executing a command
+  _send_exit_status() {
+    printf '\033]633;D;%d\033\\' "$?"
+  }
+  PROMPT_COMMAND=("$PROMPT_COMMAND" _send_exit_status)
+
+fi
+
 # define function that updates $_vcs_info and $_vcs_root
 _update_vcs_info() {
   typeset type branch