Trap on DEBUG not removed with shellhistory disable

[pawamoy]

It seems to be because trap - DEBUG is run inside of a function (_shellhistory_disable).

A quick fix for this is to use PROMPT_COMMAND to unset it instead:

new_prompt_command=${PROMPT_COMMAND//_shellhistory_after;}
PROMPT_COMMAND="trap '${trap:--}' DEBUG; PROMPT_COMMAND='${new_prompt_command}'"

Explanation:

• first we compute the new prompt command (the one without shellhistory)
• then we set PROMPT_COMMAND to:
  • a command that will update the trap (when $trap is not empty) or remove it (when $trap is empty, will be replaced by -)
  • and a command that will set it to the new prompt command