Impeccable History

history-scraper is an executable file of a small program written in Rust. Built on my system, it might not work on yours. If this is the case, you will have to compile it from source, first installing Rust and Cargo. Later, there will be added an easier way of compilation with Docker.

You can find more about hist-scraper's CLI by calling it with -h option. In case you want to amend or adjust the plugin to your needs, please, see the source code (hist-scraper.rs, hist-scraper.plugin.zsh), then contribute.

The plugin works by remembering failed commands in a /tmp/hist-scraper-nzcmds.txt during a Zsh session (a hook in precmd_functions) and removing them on exit from $HISTFILE (a hook in zshexit_functions). You can find info about errors occurred during the plugin operation at /tmp/hist-scraper-error.log.

Note: you can not remove with impeccable-history commands in $HISTFILE that failed before the installation. Also, editing HISTFILE manually will result in assigning a wrong value to HIST_SCRAPER_SKIP_ROWS for the next shell session. However, you can adjust it or set it to zero from the command line.

More About

On top of removing failed commands, impeccable-history plugin sets four Zsh options: histignorespace, histreduceblanks, histignorealldups, histnostore - for a sharper management of a user history.

Even more granular control over the lifetime of trivial commands is possible with HIST_SCRAPER_IGNORE and HISTORY_IGNORE variables. One can incorporate the adaptations of the following into their .zshrc.

ignore_list=('.{1,3}' echo clear tmux )
## Don't append the following patterns to the $history array.
HIST_SCRAPER_IGNORE="(^$(join_by '$|^' ${ignore_list[@]})$)"
unset ignore_list

## Remove these patterns from $HISTFILE on shell logout.
HISTORY_IGNORE="(mv *|mkdir *|man *|math *|type *|which *|whence *)"

Installation

For instance, with zcomet:

zcomet load lukoshkin/impeccable-history

## The command below pulls from the 'develop' branch.
# zcomet load lukoshkin/impeccable-history@develop

I guess, most of the popular plugin managers will work as well.
Just add the corresponding entry to your .zshrc.

Known issues

Zsh history file is saved in metafied format. Currently, hist-scraper reads it directly, without transforming it back to a standard encoding. That is, the plugin will not work for failed commands containing non-ASCII characters. This will be fixed in the next patch.

Possible solutions:

• metafying strings of failed commands and comparing them with
  the lines of the history file read as Vec<char> (see, e.g., this).
• feeding the last few commands of $HISTFILE converted with Zsh's history to
  hist-scraper and obtaining the indices of the lines to delete. Then doing something like

  awk 'FNR==NR{a[$0];next} !(FNR in a)' indices.txt $HISTFILE