Bash script to lint Git-tracked text files for final newline character

txtfeol.sh

#!/usr/bin/env bash
#? Lint Git-tracked text files for final newline character

set -eo pipefail

declare -i errcnt=0
declare -i total=0
declare -i done=0

while IFS= read -r file; do
    if [ "$file" = "/" ]; then
        done=1
        break
    fi
    # Check if the file is non-empty via `-s` and does not end with a newline
    # character. `tail` command gets the last byte, `od` converts it to hex,
    # `tr` removes spaces Compare against `0a` which is the hex code for
    # newline.
    if [ -s "$file" ] &&
       [ "$(tail -c1 "$file" | od -An -tx1 | tr -d ' ')" != "0a" ]; then
        echo >&2 "$file"
        errcnt=$((errcnt + 1))
    fi        
    total=$((total + 1))
done < <(
    git ls-files --eol |  # List all tracked files with their EOL status
        grep -vE '\b[iw]/-text\b' | # Exclude files marked as binary or with no EOL normalization
        cut -f2 | # Extract the file paths
        grep -vE '^(data|experiments|spikes)/'  # Exclude specific directories
    echo /
)

if [ "$done" -eq 0 ]; then
    echo >&2 "File enumeration was not completed."
    exit 1
fi

echo >&2 "$total"' files checked, '"$errcnt"' files missing a trailing newline.'
[ "$errcnt" -eq 0 ]