vsf - Very Simple Formatter

A Go CLI tool and library for column alignment and text formatting. Works great with fzf.

What it does

• Aligns text columns based on delimiters
• Integrates with fzf and Unix pipelines
• Handy for formatting Git logs, CSVs, and other structured text
• Available as both a CLI tool and Go library

Quick start

CLI Tool

go install github.com/sisoe24/vsf/cmd/vsf@latest
echo "name:city:age\njohnny:new york:30\namy:rome:25" | vsf | fzf --header-lines 1

Go Library

go get github.com/sisoe24/vsf

import "github.com/sisoe24/vsf"

input := "name:city:age\njohnny:new york:30\namy:rome:25"
aligned, err := vsf.Format(input, ":", ":")
if err != nil {
    log.Fatal(err)
}
fmt.Println(aligned)

CLI Usage

vsf [-d delimiter] [-o output_delimiter] [-header lines] [-h]

Flags:

• -d : Input delimiter (default: ":")
• -o : Output delimiter (default: same as input)
• -header : Number of header lines to preserve without alignment (default: 0)
• -h : Show help

Examples

CLI Examples

• Basic formatting

  echo "name:john\nage:30" | vsf

• Git branch formatting

  git for-each-ref --sort=-committerdate refs/heads/ --format='%(refname:short):%(committerdate:short)' | vsf -o "|" | fzf

• CSV with headers (perfect with fzf)

  cat data.csv | vsf -d ',' -header 1 | fzf --header-lines 1

• Custom delimiters

  echo "a|b|c\nlong text|short|medium" | vsf -d '|' -o ' → '

Library Examples

• Basic column alignment

  data := "name:john\nage:30\ncity:new york"
  result, _ := vsf.Format(data, ":", ":")
  // Output:
  // name : john
  // age  : 30  
  // city : new york

• CSV with headers (perfect for fzf)

  csv := "name,age,city\njohn,30,nyc\namy,25,rome"
  result, _ := vsf.FormatWithHeader(csv, ",", " | ", 1)
  // Output:
  // name,age,city
  // john | 30  | nyc
  // amy  | 25  | rome

• Parse individual lines

  columns := vsf.ParseLine("name:'john doe':30", ":")
  // columns = ["name", "'john doe'", "30"]
  // Respects quotes - won't split on delimiters inside quotes

• Custom output delimiter

  result, _ := vsf.Format(data, ":", " | ")
  // Output:
  // name | john
  // age  | 30
  // city | new york

API Reference

Functions

• Format(input, delimiter, outputDelimiter string) (string, error) - Standard column alignment
• FormatWithHeader(input, delimiter, outputDelimiter string, headerLines int) (string, error) - Column alignment preserving header lines
• ParseLine(line, delimiter string) []string - Parse a single line into columns (respects quotes)

Development

make       # Build
make test  # Run tests

Contributing

PRs welcome!

License

MIT License. See LICENSE file for more info.