Use ugrep to search file content in the Dolphin file manager (KDE/Plasma)

[AndydeCleyre]

For KDE/Plasma users, the Dolphin file manager can search through file content.

If Baloo indexing is enabled, that's used (File Search in system settings). Otherwise, ripgrep-all, then ripgrep, is tried.

You can replace the ripgrep attempts with ugrep attempts by placing a custom script at ~/.local/share/kio_filenamesearch/kio-filenamesearch-grep.

The usual version is found at /usr/share/kio_filenamesearch/kio-filenamesearch-grep, and looks like this:

default script

#!/bin/sh
set -ef

# Requirements for this script:
#
# 1. When the external search program (e.g. `rga`, `rg`) is not installed, 
#    exit with status 127. `kio-filenamesearch` (called by the Dolphin search)
#    will then use the its (slower) fallback search code.
#
# 2. STDOUT should only contain paths separated by '\0'. Paths can be either
#    absolute or relative to the current directory.
#
# 3. If search is successful, either the exit code should be 0, or STDERR should
#    not contain any output. Because `rg` returns 1 when no matches are found,
#    and returns 2 when there are broken symlinks or permission errors, we can't
#    rely solely on the exit code being 0 to determine success. So we also considers
#    a non-zero exit code AND an empty STDERR to be a success.
#
# 4. So, when the search fails (other than the "not installed" case in point 1),
#    in addition for exiting with a non-zero status, you should also print an error
#    message to STDERR. The message will be displayed to the user in Dolphin.

case $1 in
    --check)
        if rga --version 2>/dev/null | grep -q 'ripgrep-all'; then
            exit 0
        elif rg --version 2>/dev/null | grep -q 'ripgrep'; then
            exit 0
        else
            exit 127
        fi
        ;;

    --run)
        # These options are required for the search to work.
        REQUIRED_OPTIONS="--files-with-matches --null --no-messages"
        
        # You can modify these options.
        # -j2:             Limit search to 2 threads. Remove this to get maximum performance on SSD, but it will hurt performance badly on HDD.
        # --line-buffered: Show each result in Dolphin as soon as it is found. Removing this might speed up the search a tiny bit, but
        #                  the first result might appear later.
        # -L:              Follow symlinks.
        # --hidden:        Don't skip hidden files and directories.
        # --no-ignore:     Don't respect .gitignore/.ignore settings.
        OPTIONS="-j2 --line-buffered -L --hidden --no-ignore"
        
        if rga --version 2>/dev/null | grep -q 'ripgrep-all'; then
            exec rga $OPTIONS $REQUIRED_OPTIONS -e "$2" .
        elif rg --version 2>/dev/null | grep -q 'ripgrep'; then
            exec rg $OPTIONS $REQUIRED_OPTIONS -e "$2" .
        else
            exit 127
        fi
        ;;

    *)
        echo "Invalid argument: $1" >&2
        exit 1
        ;;
esac

You can start with that and modify it as you like. My current version is:

ugrep script

#!/bin/sh
set -ef

export PATH="$HOME/.local/share/mise/shims:$PATH"

case $1 in
    --check)
        if command -v ugrep+ >/dev/null 2>&1; then
            exit 0
        elif command -v ugrep >/dev/null 2>&1; then
            exit 0
        else
            exit 127
        fi
        ;;

    --run)
        REQUIRED_OPTIONS="--dereference-recursive --files-with-matches --no-messages --null --pretty=never"

        # --hidden:        Don't skip hidden files and directories.
        # --line-buffered: Show each result in Dolphin as soon as it is found.
        # --perl-regexp:   Interpret search pattern with PCRE2.
        # --smart-case:    Ignore case when search pattern is lower case.
        OPTIONS="--hidden --line-buffered --perl-regexp --smart-case"

        # --jobs=2:                 Limit search to 2 threads. Remove this to get maximum performance on SSD, but it will hurt performance badly on HDD.
        # --no-dereference:         Don't follow symlinks.
        # --ignore-files:           Abide .gitignore settings.
        # --ignore-files=.ignore:   Abide .ignore settings.

        if command -v ugrep+ >/dev/null 2>&1; then
            # shellcheck disable=SC2086
            exec ugrep+ $OPTIONS $REQUIRED_OPTIONS -e "$2" .
        elif command -v ugrep >/dev/null 2>&1; then
            # shellcheck disable=SC2086
            exec ugrep $OPTIONS $REQUIRED_OPTIONS -e "$2" .
        else
            exit 127
        fi
        ;;

    *)
        echo "Invalid argument: $1" >&2
        exit 1
        ;;
esac

That PATH adjustment is needed for me because I have pandoc installed via mise. In the future, or on other systems, I might have other relevant tools (like ugrep itself) installed via mise as well.