Add bash history saving and restoring (first version).

This does not yet have flag to turn the feature off.

scripts/helpers.sh

@@ -63,3 +63,8 @@ resurrect_file_path() {
 last_resurrect_file() {
 	echo "$(resurrect_dir)/last"
 }
+
+resurrect_history_file() {
+	local pane_id="$1"
+	echo "$(resurrect_dir)/bash_history-${pane_id}"
+}

scripts/restore.sh

@@ -141,6 +141,21 @@ restore_all_panes() {
 	done < $(last_resurrect_file)
 }
 
+restore_shell_history() {
+	awk 'BEGIN { FS="\t"; OFS="\t" } /^pane/ { print $2, $3, $7, $10; }' $(last_resurrect_file) |
+		while IFS=$'\t' read session_name window_number pane_index pane_command; do
+		 if ! is_pane_registered_as_existing "$session_name" "$window_number" "$pane_index"; then
+				if [ "$pane_command" = "bash" ]; then
+					local pane_id="$session_name:$window_number.$pane_index"
+					# tmux send-keys has -R option that should reset the terminal.
+					# However, appending 'clear' to the command seems to work more reliably.
+					local read_command="history -r '$(resurrect_history_file "$pane_id")'; clear"
+					tmux send-keys -t "$pane_id" "$read_command" C-m
+				fi
+			fi
+		done
+}
+
 restore_all_pane_processes() {
 	if restore_pane_processes_enabled; then
 		local pane_full_command
@@ -196,6 +211,7 @@ main() {
 		start_spinner "Restoring..." "Tmux restore complete!"
 		restore_all_panes
 		restore_pane_layout_for_each_window >/dev/null 2>&1
+		restore_shell_history
 		restore_all_pane_processes
 		# below functions restore exact cursor positions
 		restore_active_pane_for_each_window

scripts/save.sh

@@ -83,6 +83,19 @@ pane_full_command() {
 	$strategy_file "$pane_pid"
 }
 
+save_shell_history() {
+	local pane_id="$1"
+	local pane_command="$2"
+	if [ "$pane_command" = "bash" ]; then
+		# leading space prevents the command from being saved to history
+		# (assuming default HISTCONTROL settings)
+		local write_command=" history -w '$(resurrect_history_file "$pane_id")'"
+		# C-e C-u is a Bash shortcut sequence to clear whole line. It is necessary to
+		# delete any pending input so it does not interfere with our history command.
+		tmux send-keys -t "$pane_id" C-e C-u "$write_command" C-m
+	fi
+}
+
 # translates pane pid to process command running inside a pane
 dump_panes() {
 	local full_command
@@ -91,6 +104,7 @@ dump_panes() {
 		while IFS=$'\t' read line_type session_name window_number window_name window_active window_flags pane_index dir pane_active pane_command pane_pid; do
 			full_command="$(pane_full_command $pane_pid)"
 			echo "${line_type}${d}${session_name}${d}${window_number}${d}${window_name}${d}${window_active}${d}${window_flags}${d}${pane_index}${d}${dir}${d}${pane_active}${d}${pane_command}${d}:${full_command}"
+			save_shell_history "$session_name:$window_number.$pane_index" "$pane_command"
 		done
 }