separate fields by comma using bash

Question

How do I place commas between fields?

Input data

12123 \'QA test case 1\' \'QA environment\'   
12234 \'UAT test case 1\' \'UAT environment\'  
         


        

Answer 1

A naïve bash implementation that assumes that no (escaped) ' instances ever appear inside a field:

• Original single-quoting is preserved.
• Accepts any number of input fields.
• Any fields may be single-quoted.
• Caveat: whitespace between fields is normalized (replaced with a single space each), as is whitespace inside a quoted field.

Input is assumed to come from file file:

# Read all whitespace-separated tokens (potentially across quoted field boundaries).
while read -ra tkns; do  
  # Initialize per-line variables.
  numTkns=${#tkns[@]} i=0 inField=0
  # Loop over all tokens.
  for tkn in "${tkns[@]}"; do
    # Determine if we're inside a quoted field.
    [[ $tkn == \'* ]] && inField=1
    [[ $tkn == *\' ]] && inField=0
    # Determine the output separator:
    if (( ++i == numTkns )); then
      sep=$'\n' # last token, terminate output line with \n
    else
      # inside a field: use just a space; between fields: use ', '
      (( inField )) && sep=' ' || sep=', '
    fi
    # Output token and separator.
    printf '%s%s' "$tkn" "$sep"
  done
done < file