diffmatchpatch/diffmatchpatch.go

// Copyright (c) 2012-2016 The go-diff authors. All rights reserved.
// https://github.com/sergi/go-diff
// See the included LICENSE file for license details.
//
// go-diff is a Go implementation of Google's Diff, Match, and Patch library
// Original library is Copyright (c) 2006 Google Inc.
// http://code.google.com/p/google-diff-match-patch/

// Package diffmatchpatch offers robust algorithms to perform the operations required for synchronizing plain text.
package diffmatchpatch

import (
	"time"
)

// DiffMatchPatch holds the configuration for diff-match-patch operations.
type DiffMatchPatch struct {
	// Number of seconds to map a diff before giving up (0 for infinity).
	DiffTimeout time.Duration
	// Cost of an empty edit operation in terms of edit characters.
	DiffEditCost int
	// How far to search for a match (0 = exact location, 1000+ = broad match). A match this many characters away from the expected location will add 1.0 to the score (0.0 is a perfect match).
	MatchDistance int
	// When deleting a large block of text (over ~64 characters), how close do the contents have to be to match the expected contents. (0.0 = perfection, 1.0 = very loose).  Note that MatchThreshold controls how closely the end points of a delete need to match.
	PatchDeleteThreshold float64
	// Chunk size for context length.
	PatchMargin int
	// The number of bits in an int.
	MatchMaxBits int
	// At what point is no match declared (0.0 = perfection, 1.0 = very loose).
	MatchThreshold float64
}

// New creates a new DiffMatchPatch object with default parameters.
func New() *DiffMatchPatch {
	// Defaults.
	return &DiffMatchPatch{
		DiffTimeout:          time.Second,
		DiffEditCost:         4,
		MatchThreshold:       0.5,
		MatchDistance:        1000,
		PatchDeleteThreshold: 0.5,
		PatchMargin:          4,
		MatchMaxBits:         32,
	}
}