diff

Documentation

Overview

Package diff implement text comparison.

Index

• Constants
• Variables
• func Bytes(oldb, newb []byte) (equal bool)
• func BytesRatio(old, new []byte, minTokenLen int) (ratio float32, m int, maxlen int)
• func Lines(old, new []byte, atx, aty int) (adds, dels text.Chunks)
• func ReadLines(f string) (lines text.Lines, e error)
• type Data
  • func Files(oldf, newf string, difflevel int) (diffs Data, e error)
  • func (diffs *Data) GetAllAdds() (chunks text.Chunks)
  • func (diffs *Data) GetAllDels() (chunks text.Chunks)
  • func (diffs *Data) PushAdd(new text.Line)
  • func (diffs *Data) PushChange(old, new text.Line)
  • func (diffs *Data) PushDel(old text.Line)
  • func (diffs Data) String() (s string)
• type LineChange
  • func NewLineChange(old, new text.Line) *LineChange
  • func (change LineChange) String() string
• type LineChanges
  • func (changes *LineChanges) GetAllAdds() (allAdds text.Chunks)
  • func (changes *LineChanges) GetAllDels() (allDels text.Chunks)

Constants

const (
	// LevelLines define that we want only lines change set.
	LevelLines = iota
	// LevelWords define that we want the change not only capture the
	// different per line, but also changes inside the line.
	LevelWords
)

const (
	// DefMatchLen minimum number of bytes used for searching the next
	// matched chunk in line.
	DefMatchLen = 5
	// DefMatchRatio define default minimum match ratio to be considered as
	// change.
	DefMatchRatio = 0.7
)

Variables

var (
	// DefDelimiter define default delimiter for new line.
	DefDelimiter = byte('\n')
)

Functions

func Bytes

func Bytes(oldb, newb []byte) (equal bool)

Bytes compare two slice of bytes and return true if equal or false otherwise.

func BytesRatio

func BytesRatio(old, new []byte, minTokenLen int) (
	ratio float32, m int, maxlen int,
)

BytesRatio compare two slice of bytes and return ratio of matching bytes. The ratio in in range of 0.0 to 1.0, where 1.0 if both are similar, and 0.0 if no matchs even found. `minTokenLen` define the minimum length of token for searching in both of slice.

func Lines

func Lines(old, new []byte, atx, aty int) (adds, dels text.Chunks)

Lines given two similar lines, find and return the differences (additions and deletion) between them.

Case 1: addition on new or deletion on old.

old: 00000
new: 00000111

or

old: 00000111
new: 00000

Case 2: addition on new line

old: 000000
new: 0001000

Case 3: deletion on old line (reverse of case 2)

old: 0001000
new: 000000

Case 4: change happened in the beginning

old: 11000
new: 22000

Case 5: both changed

old: 0001000
new: 0002000

func ReadLines

func ReadLines(f string) (lines text.Lines, e error)

ReadLines return lines in the file `f`.

Types

type Data

type Data struct {
	Adds    text.Lines
	Dels    text.Lines
	Changes LineChanges
}

Data represent additions, deletions, and changes between two text.

func Files

func Files(oldf, newf string, difflevel int) (diffs Data, e error)

Files compare two files.

func (*Data) GetAllAdds

func (diffs *Data) GetAllAdds() (chunks text.Chunks)

GetAllAdds return chunks of additions including in line changes.

func (*Data) GetAllDels

func (diffs *Data) GetAllDels() (chunks text.Chunks)

GetAllDels return chunks of deletions including in line changes.

func (*Data) PushAdd

func (diffs *Data) PushAdd(new text.Line)

PushAdd will add new line to diff set.

func (*Data) PushChange

func (diffs *Data) PushChange(old, new text.Line)

PushChange set to diff data.

func (*Data) PushDel

func (diffs *Data) PushDel(old text.Line)

PushDel will add deletion line to diff set.

func (Data) String

func (diffs Data) String() (s string)

String return formatted data.

type LineChange

type LineChange struct {
	Old  text.Line
	New  text.Line
	Adds text.Chunks
	Dels text.Chunks
}

LineChange represent one change in text.

func NewLineChange

func NewLineChange(old, new text.Line) *LineChange

NewLineChange create a pointer to new LineChange object.

func (LineChange) String

func (change LineChange) String() string

String return formatted content of LineChange.

type LineChanges

type LineChanges []LineChange

LineChanges represents a set of change in text.

func (*LineChanges) GetAllAdds

func (changes *LineChanges) GetAllAdds() (allAdds text.Chunks)

GetAllAdds return all addition chunks.

func (*LineChanges) GetAllDels

func (changes *LineChanges) GetAllDels() (allDels text.Chunks)

GetAllDels return all deleted chunks.