bash: reverse % + clear incomplete line a la zsh

bash/prompt

@@ -41,6 +41,23 @@ __tpwd() {
     __truncate_path "$PWD"
 }
 
+clear_incomplete_line() {
+    # prevent the terminal response to be displayed
+    stty raw -echo
+    # ask for cursor position
+    echo -en "\033[6n"
+    # read answer
+    IFS=';' read -r -d R -a pos
+    # set back terminal to human mode
+    stty -raw echo
+    # extract tput-compatible answer
+    local row=$((${pos[0]:2} - 1))
+    local col=$((${pos[1]} - 1))
+
+    # not on first column? clean up!
+    [[ $col != 0 ]] && printf "\e[7m%%\e[m%$((COLUMNS-1))s\r"
+}
+
 # git prompt info
 source $DOTFILES_BASH_DIR/git_prompt_info
 GIT_PS1_SHOWDIRTYSTATE=1

bash/rc

@@ -7,7 +7,9 @@ source $DOTFILES_BASH_DIR/history
 source $DOTFILES_BASH_DIR/term_title
 source $DOTFILES_BASH_DIR/completion
 
-PROMPT_COMMAND="set_prompt; set_term_title;"
+PROMPT_COMMAND="set_prompt;"
+PROMPT_COMMAND+="set_term_title;"
+PROMPT_COMMAND+="clear_incomplete_line;"
 
 # Make bash check its window size after a process completes
 shopt -s checkwinsize