go-fractured-json

Go implementation of FracturedJson-style JSON formatting.

Source references used for this port:

• C# implementation: ../FracturedJson
• Project wiki: ../FracturedJson.wiki

Current Status

Implemented in this repo:

• Ordered JSON parser (preserves object property order from input)
• FracturedJson-style options with v5 default values
• Inline formatting for arrays/objects based on complexity and line length
• Expanded formatting with object key alignment
• Compact multi-line array formatting (multiple items per row)
• Table formatting for similar array rows (array-of-arrays and array-of-objects)
• Number list alignment modes (Left, Right, Decimal, Normalize) for table-formatted numeric columns
• JSON-with-comments input handling (TreatAsError, Remove, Preserve)
• Trailing-comma policy handling via AllowTrailingCommas
• Blank-line preservation of leading/trailing blank runs via PreserveBlankLines
• Convenience APIs for Reformat, Serialize, and Minify

Install / Use

go test ./...

Regenerate golden files in testdata using the C# formatter:

./scripts/regenerate-golden.sh

Optional flags:

# Regenerate one case by name
./scripts/regenerate-golden.sh --only wiki_always_expand_depth_1

# Use a non-default FracturedJson checkout
./scripts/regenerate-golden.sh --fracturedjson ../FracturedJson

Requirements for regeneration:

• .NET SDK (dotnet) on PATH
• C# FracturedJson repo at ../FracturedJson or passed via --fracturedjson

package main

import (
	"fmt"

	fj "github.com/FileFormatInfo/go-fractured-json"
)

func main() {
	input := `{"items":[{"id":1,"name":"alpha"},{"id":2,"name":"beta"}],"ok":true}`

	f := fj.NewFormatter()
	f.Options.MaxTotalLineLength = 80

	out, err := f.Reformat(input, 0)
	if err != nil {
		panic(err)
	}
	fmt.Println(out)
}

API

• type Formatter struct { Options Options }
• func NewFormatter() *Formatter
• func (f *Formatter) Reformat(input string, startingDepth int) (string, error)
• func (f *Formatter) Serialize(obj any, startingDepth int) (string, error)
• func (f *Formatter) Minify(input string) (string, error)
• Convenience wrappers:
  • Reformat(input string) (string, error)
  • Serialize(obj any) (string, error)
  • Minify(input string) (string, error)