fix: improve error messages and grep handling

gh-find-code

@@ -294,7 +294,7 @@ validate_environment() {
  # Check if the necessary history file exists and is readable and writable
  if ((GHFC_HISTORY_LIMIT)); then
  if [[ -d $GHFC_HISTORY_FILE ]]; then
- die "$GHFC_HISTORY_FILE is a directory"
+ die "'$GHFC_HISTORY_FILE' is a directory. Please specify a file path for the GHFC_HISTORY_FILE."
  fi
 
  if [[ ! -f $GHFC_HISTORY_FILE ]]; then
@@ -683,7 +683,9 @@ gh_query() {
  grep_args+=("--regexp=$pattern")
  done
 
- # Run the grep command directly with the expanded array
+ # Use the '--text' flag, as grep will simply print 'Binary file … matches' if
+ # the file contains binary characters. It won't even throw an error.
+ # https://unix.stackexchange.com/questions/19907
  command grep --color=never --line-number --text --fixed-strings "${grep_args[@]}" -- \
  "${store_file_contents}_${index}_fetched" 2>"${redirect_location}" |
  command cut -d: -f1 >>"${store_file_contents}_${index}_line_numbers"
@@ -782,13 +784,15 @@ view_contents() {
  bat_args+=("--language=${file_extension}")
  fi
  line_numbers=()
- while IFS= read -r matched_line; do
- line_numbers+=("$matched_line")
- # NOTE: The '--line-range' in 'bat' overrides preceding flags. However, the
- # '-H, --highlight-line' attribute can be utilized multiple times.
- # https://github.com/sharkdp/bat/pull/162#pullrequestreview-125072252
- # use the short form to avoid making the command unnecessarily long
- bat_args+=("-H=${matched_line}")
+ while IFS=$'\n' read -r matched_line; do
+ if [[ $matched_line =~ ^[0-9]+ ]]; then
+ line_numbers+=("$matched_line")
+ # NOTE: The '--line-range' in 'bat' overrides preceding flags. However, the
+ # '-H, --highlight-line' attribute can be utilized multiple times.
+ # https://github.com/sharkdp/bat/pull/162#pullrequestreview-125072252
+ # use the short form to avoid making the command unnecessarily long
+ bat_args+=("-H=${matched_line}")
+ fi
  done <"${store_file_contents}_${index}_line_numbers"
 
  file_name=$(command basename "$file_path")