pax_global_header 0000666 0000000 0000000 00000000064 13660101765 0014517 g ustar 00root root 0000000 0000000 52 comment=4685cd721e376b24d1a79bd0aef439a7f83efd92
go-difflib-1.2.0/ 0000775 0000000 0000000 00000000000 13660101765 0013521 5 ustar 00root root 0000000 0000000 go-difflib-1.2.0/LICENSE 0000664 0000000 0000000 00000002645 13660101765 0014535 0 ustar 00root root 0000000 0000000 Copyright (c) 2013, Patrick Mezard
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are
met:
Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
The names of its contributors may not be used to endorse or promote
products derived from this software without specific prior written
permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
go-difflib-1.2.0/README.md 0000664 0000000 0000000 00000002765 13660101765 0015012 0 ustar 00root root 0000000 0000000 go-difflib
==========
The previous owner of this project (pmezard) did not have the time to continue
working on it. Additionally I (ianbruene) needed additional ported features.
For these reasons I have taken over maintenance and further development of the
project.
[](https://godoc.org/github.com/ianbruene/go-difflib/difflib)
Go-difflib is an as yet partial port of python 3's difflib package.
The following publicly visible classes and functions have been ported:
* `SequenceMatcher`
* `Differ`
* `unified_diff()`
* `context_diff()`
## Installation
```bash
$ go get github.com/ianbruene/go-difflib/difflib
```
### UnifiedDiff Quick Start
Diffs are configured with Unified (or ContextDiff) structures, and can
be output to an io.Writer or returned as a string.
```Go
diff := difflib.LineDiffParams{
A: difflib.SplitLines("foo\nbar\n"),
B: difflib.SplitLines("foo\nbaz\n"),
FromFile: "Original",
ToFile: "Current",
Context: 3,
}
text, _ := difflib.GetUnifiedDiffString(diff)
fmt.Printf(text)
```
would output:
```
--- Original
+++ Current
@@ -1,3 +1,3 @@
foo
-bar
+baz
```
### Differ Quick Start
Differ has been implemented primarily for the Compare() function at this time.
```Go
diff := difflib.NewDiffer()
out, err := diff.Compare(
[]string{"foo\n", "bar\n", "baz\n"},
[]string{"foo\n", "bar1\n", "asdf\n", "baz\n"})
```
would output:
```
foo
- bar
+ bar1
? +
+ asdf
baz
```
go-difflib-1.2.0/difflib/ 0000775 0000000 0000000 00000000000 13660101765 0015120 5 ustar 00root root 0000000 0000000 go-difflib-1.2.0/difflib/bytes/ 0000775 0000000 0000000 00000000000 13660101765 0016246 5 ustar 00root root 0000000 0000000 go-difflib-1.2.0/difflib/bytes/bytes.go 0000664 0000000 0000000 00000101656 13660101765 0017734 0 ustar 00root root 0000000 0000000 // Package difflib is a partial port of Python difflib module.
//
// It provides tools to compare sequences of strings and generate textual diffs.
//
// The following class and functions have been ported:
//
// - SequenceMatcher
//
// - unified_diff
//
// - context_diff
//
// Getting unified diffs was the main goal of the port. Keep in mind this code
// is mostly suitable to output text differences in a human friendly way, there
// are no guarantees generated diffs are consumable by patch(1).
package bytes
import (
"bufio"
"bytes"
"errors"
"fmt"
"io"
"strings"
"unicode"
"hash/adler32"
)
func min(a, b int) int {
if a < b {
return a
}
return b
}
func max(a, b int) int {
if a > b {
return a
}
return b
}
func calculateRatio(matches, length int) float64 {
if length > 0 {
return 2.0 * float64(matches) / float64(length)
}
return 1.0
}
func listifyString(str []byte) (lst [][]byte) {
lst = make([][]byte, len(str))
for i := range str {
lst[i] = str[i:i+1]
}
return lst
}
type Match struct {
A int
B int
Size int
}
type OpCode struct {
Tag byte
I1 int
I2 int
J1 int
J2 int
}
type lineHash uint32
func _hash(line []byte) lineHash {
return lineHash(adler32.Checksum(line))
}
// This is essentially a map from lines to line numbers, so that later it can
// be made a bit cleverer than the standard map in that it will not need to
// store copies of the lines.
// It needs to hold a reference to the underlying slice of lines.
type B2J struct {
store map[lineHash] [][]int
b [][]byte
}
type lineType int8
const (
lineNONE lineType = 0
lineNORMAL lineType = 1
lineJUNK lineType = -1
linePOPULAR lineType = -2
)
func (b2j *B2J) _find(line *[]byte) (h lineHash, slotIndex int,
slot []int, lt lineType) {
h = _hash(*line)
for slotIndex, slot = range b2j.store[h] {
// Thanks to the qualities of sha1, the probability of having more than
// one line content with the same hash is very low. Nevertheless, store
// each of them in a different slot, that we can differentiate by
// looking at the line contents in the b slice.
// In place of all the line numbers where the line appears, a slot can
// also contain [lineno, -1] if b[lineno] is junk.
if bytes.Equal(*line, b2j.b[slot[0]]) {
// The content already has a slot in its hash bucket.
if len(slot) == 2 && slot[1] < 0 {
lt = lineType(slot[1])
} else {
lt = lineNORMAL
}
return // every return variable has the correct value
}
}
// The line content still has no slot.
slotIndex = -1
slot = nil
lt = lineNONE
return
}
func newB2J (b [][]byte, isJunk func([]byte) bool, autoJunk bool) *B2J {
b2j := B2J{store: map[lineHash] [][]int{}, b: b}
ntest := len(b)
if autoJunk && ntest >= 200 {
ntest = ntest/100 + 1
}
for lineno, line := range b {
h, slotIndex, slot, lt := b2j._find(&line)
switch lt {
case lineNORMAL:
if len(slot) >= ntest {
b2j.store[h][slotIndex] = []int{slot[0], int(linePOPULAR)}
} else {
b2j.store[h][slotIndex] = append(slot, lineno)
}
case lineNONE:
if isJunk != nil && isJunk(line) {
b2j.store[h] = append(b2j.store[h], []int{lineno, int(lineJUNK)})
} else {
b2j.store[h] = append(b2j.store[h], []int{lineno})
}
default:
}
}
return &b2j
}
func (b2j *B2J) get(line []byte) []int {
_, _, slot, lt := b2j._find(&line)
if lt == lineNORMAL {
return slot
}
return []int{}
}
func (b2j *B2J) isBJunk(line []byte) bool {
_, _, _, lt := b2j._find(&line)
return lt == lineJUNK
}
// SequenceMatcher compares sequence of strings. The basic
// algorithm predates, and is a little fancier than, an algorithm
// published in the late 1980's by Ratcliff and Obershelp under the
// hyperbolic name "gestalt pattern matching". The basic idea is to find
// the longest contiguous matching subsequence that contains no "junk"
// elements (R-O doesn't address junk). The same idea is then applied
// recursively to the pieces of the sequences to the left and to the right
// of the matching subsequence. This does not yield minimal edit
// sequences, but does tend to yield matches that "look right" to people.
//
// SequenceMatcher tries to compute a "human-friendly diff" between two
// sequences. Unlike e.g. UNIX(tm) diff, the fundamental notion is the
// longest *contiguous* & junk-free matching subsequence. That's what
// catches peoples' eyes. The Windows(tm) windiff has another interesting
// notion, pairing up elements that appear uniquely in each sequence.
// That, and the method here, appear to yield more intuitive difference
// reports than does diff. This method appears to be the least vulnerable
// to synching up on blocks of "junk lines", though (like blank lines in
// ordinary text files, or maybe "
" lines in HTML files). That may be
// because this is the only method of the 3 that has a *concept* of
// "junk" .
//
// Timing: Basic R-O is cubic time worst case and quadratic time expected
// case. SequenceMatcher is quadratic time for the worst case and has
// expected-case behavior dependent in a complicated way on how many
// elements the sequences have in common; best case time is linear.
type SequenceMatcher struct {
a [][]byte
b [][]byte
b2j B2J
IsJunk func([]byte) bool
autoJunk bool
matchingBlocks []Match
fullBCount map[lineHash]int
opCodes []OpCode
}
func NewMatcher(a, b [][]byte) *SequenceMatcher {
m := SequenceMatcher{autoJunk: true}
m.SetSeqs(a, b)
return &m
}
func NewMatcherWithJunk(a, b [][]byte, autoJunk bool,
isJunk func([]byte) bool) *SequenceMatcher {
m := SequenceMatcher{IsJunk: isJunk, autoJunk: autoJunk}
m.SetSeqs(a, b)
return &m
}
// Set two sequences to be compared.
func (m *SequenceMatcher) SetSeqs(a, b [][]byte) {
m.SetSeq1(a)
m.SetSeq2(b)
}
// Set the first sequence to be compared. The second sequence to be compared is
// not changed.
//
// SequenceMatcher computes and caches detailed information about the second
// sequence, so if you want to compare one sequence S against many sequences,
// use .SetSeq2(s) once and call .SetSeq1(x) repeatedly for each of the other
// sequences.
//
// See also SetSeqs() and SetSeq2().
func (m *SequenceMatcher) SetSeq1(a [][]byte) {
if &a == &m.a {
return
}
m.a = a
m.matchingBlocks = nil
m.opCodes = nil
}
// Set the second sequence to be compared. The first sequence to be compared is
// not changed.
func (m *SequenceMatcher) SetSeq2(b [][]byte) {
if &b == &m.b {
return
}
m.b = b
m.matchingBlocks = nil
m.opCodes = nil
m.fullBCount = nil
m.chainB()
}
func (m *SequenceMatcher) chainB() {
// Populate line -> index mapping
b2j := *newB2J(m.b, m.IsJunk, m.autoJunk)
m.b2j = b2j
}
// Find longest matching block in a[alo:ahi] and b[blo:bhi].
//
// If IsJunk is not defined:
//
// Return (i,j,k) such that a[i:i+k] is equal to b[j:j+k], where
// alo <= i <= i+k <= ahi
// blo <= j <= j+k <= bhi
// and for all (i',j',k') meeting those conditions,
// k >= k'
// i <= i'
// and if i == i', j <= j'
//
// In other words, of all maximal matching blocks, return one that
// starts earliest in a, and of all those maximal matching blocks that
// start earliest in a, return the one that starts earliest in b.
//
// If IsJunk is defined, first the longest matching block is
// determined as above, but with the additional restriction that no
// junk element appears in the block. Then that block is extended as
// far as possible by matching (only) junk elements on both sides. So
// the resulting block never matches on junk except as identical junk
// happens to be adjacent to an "interesting" match.
//
// If no blocks match, return (alo, blo, 0).
func (m *SequenceMatcher) findLongestMatch(alo, ahi, blo, bhi int) Match {
// CAUTION: stripping common prefix or suffix would be incorrect.
// E.g.,
// ab
// acab
// Longest matching block is "ab", but if common prefix is
// stripped, it's "a" (tied with "b"). UNIX(tm) diff does so
// strip, so ends up claiming that ab is changed to acab by
// inserting "ca" in the middle. That's minimal but unintuitive:
// "it's obvious" that someone inserted "ac" at the front.
// Windiff ends up at the same place as diff, but by pairing up
// the unique 'b's and then matching the first two 'a's.
besti, bestj, bestsize := alo, blo, 0
// find longest junk-free match
// during an iteration of the loop, j2len[j] = length of longest
// junk-free match ending with a[i-1] and b[j]
N := bhi - blo
j2len := make([]int, N)
newj2len := make([]int, N)
var indices []int
for i := alo; i != ahi; i++ {
// look at all instances of a[i] in b; note that because
// b2j has no junk keys, the loop is skipped if a[i] is junk
newindices := m.b2j.get(m.a[i])
for _, j := range newindices {
// a[i] matches b[j]
if j < blo {
continue
}
if j >= bhi {
break
}
k := 1
if j > blo {
k = j2len[j-1-blo] + 1
}
newj2len[j-blo] = k
if k > bestsize {
besti, bestj, bestsize = i-k+1, j-k+1, k
}
}
// j2len = newj2len, clear and reuse j2len as newj2len
for _, j := range indices {
if j < blo {
continue
}
if j >= bhi {
break
}
j2len[j-blo] = 0
}
indices = newindices
j2len, newj2len = newj2len, j2len
}
// Extend the best by non-junk elements on each end. In particular,
// "popular" non-junk elements aren't in b2j, which greatly speeds
// the inner loop above, but also means "the best" match so far
// doesn't contain any junk *or* popular non-junk elements.
for besti > alo && bestj > blo && !m.b2j.isBJunk(m.b[bestj-1]) &&
bytes.Equal(m.a[besti-1], m.b[bestj-1]) {
besti, bestj, bestsize = besti-1, bestj-1, bestsize+1
}
for besti+bestsize < ahi && bestj+bestsize < bhi &&
!m.b2j.isBJunk(m.b[bestj+bestsize]) &&
bytes.Equal(m.a[besti+bestsize], m.b[bestj+bestsize]) {
bestsize += 1
}
// Now that we have a wholly interesting match (albeit possibly
// empty!), we may as well suck up the matching junk on each
// side of it too. Can't think of a good reason not to, and it
// saves post-processing the (possibly considerable) expense of
// figuring out what to do with it. In the case of an empty
// interesting match, this is clearly the right thing to do,
// because no other kind of match is possible in the regions.
for besti > alo && bestj > blo && m.b2j.isBJunk(m.b[bestj-1]) &&
bytes.Equal(m.a[besti-1], m.b[bestj-1]) {
besti, bestj, bestsize = besti-1, bestj-1, bestsize+1
}
for besti+bestsize < ahi && bestj+bestsize < bhi &&
m.b2j.isBJunk(m.b[bestj+bestsize]) &&
bytes.Equal(m.a[besti+bestsize], m.b[bestj+bestsize]) {
bestsize += 1
}
return Match{A: besti, B: bestj, Size: bestsize}
}
// Return list of triples describing matching subsequences.
//
// Each triple is of the form (i, j, n), and means that
// a[i:i+n] == b[j:j+n]. The triples are monotonically increasing in
// i and in j. It's also guaranteed that if (i, j, n) and (i', j', n') are
// adjacent triples in the list, and the second is not the last triple in the
// list, then i+n != i' or j+n != j'. IOW, adjacent triples never describe
// adjacent equal blocks.
//
// The last triple is a dummy, (len(a), len(b), 0), and is the only
// triple with n==0.
func (m *SequenceMatcher) GetMatchingBlocks() []Match {
if m.matchingBlocks != nil {
return m.matchingBlocks
}
var matchBlocks func(alo, ahi, blo, bhi int, matched []Match) []Match
matchBlocks = func(alo, ahi, blo, bhi int, matched []Match) []Match {
match := m.findLongestMatch(alo, ahi, blo, bhi)
i, j, k := match.A, match.B, match.Size
if match.Size > 0 {
if alo < i && blo < j {
matched = matchBlocks(alo, i, blo, j, matched)
}
matched = append(matched, match)
if i+k < ahi && j+k < bhi {
matched = matchBlocks(i+k, ahi, j+k, bhi, matched)
}
}
return matched
}
matched := matchBlocks(0, len(m.a), 0, len(m.b), nil)
// It's possible that we have adjacent equal blocks in the
// matching_blocks list now.
nonAdjacent := []Match{}
i1, j1, k1 := 0, 0, 0
for _, b := range matched {
// Is this block adjacent to i1, j1, k1?
i2, j2, k2 := b.A, b.B, b.Size
if i1+k1 == i2 && j1+k1 == j2 {
// Yes, so collapse them -- this just increases the length of
// the first block by the length of the second, and the first
// block so lengthened remains the block to compare against.
k1 += k2
} else {
// Not adjacent. Remember the first block (k1==0 means it's
// the dummy we started with), and make the second block the
// new block to compare against.
if k1 > 0 {
nonAdjacent = append(nonAdjacent, Match{i1, j1, k1})
}
i1, j1, k1 = i2, j2, k2
}
}
if k1 > 0 {
nonAdjacent = append(nonAdjacent, Match{i1, j1, k1})
}
nonAdjacent = append(nonAdjacent, Match{len(m.a), len(m.b), 0})
m.matchingBlocks = nonAdjacent
return m.matchingBlocks
}
// Return list of 5-tuples describing how to turn a into b.
//
// Each tuple is of the form (tag, i1, i2, j1, j2). The first tuple
// has i1 == j1 == 0, and remaining tuples have i1 == the i2 from the
// tuple preceding it, and likewise for j1 == the previous j2.
//
// The tags are characters, with these meanings:
//
// 'r' (replace): a[i1:i2] should be replaced by b[j1:j2]
//
// 'd' (delete): a[i1:i2] should be deleted, j1==j2 in this case.
//
// 'i' (insert): b[j1:j2] should be inserted at a[i1:i1], i1==i2 in this case.
//
// 'e' (equal): a[i1:i2] == b[j1:j2]
func (m *SequenceMatcher) GetOpCodes() []OpCode {
if m.opCodes != nil {
return m.opCodes
}
i, j := 0, 0
matching := m.GetMatchingBlocks()
opCodes := make([]OpCode, 0, len(matching))
for _, m := range matching {
// invariant: we've pumped out correct diffs to change
// a[:i] into b[:j], and the next matching block is
// a[ai:ai+size] == b[bj:bj+size]. So we need to pump
// out a diff to change a[i:ai] into b[j:bj], pump out
// the matching block, and move (i,j) beyond the match
ai, bj, size := m.A, m.B, m.Size
tag := byte(0)
if i < ai && j < bj {
tag = 'r'
} else if i < ai {
tag = 'd'
} else if j < bj {
tag = 'i'
}
if tag > 0 {
opCodes = append(opCodes, OpCode{tag, i, ai, j, bj})
}
i, j = ai+size, bj+size
// the list of matching blocks is terminated by a
// sentinel with size 0
if size > 0 {
opCodes = append(opCodes, OpCode{'e', ai, i, bj, j})
}
}
m.opCodes = opCodes
return m.opCodes
}
// Isolate change clusters by eliminating ranges with no changes.
//
// Return a generator of groups with up to n lines of context.
// Each group is in the same format as returned by GetOpCodes().
func (m *SequenceMatcher) GetGroupedOpCodes(n int) [][]OpCode {
if n < 0 {
n = 3
}
codes := m.GetOpCodes()
if len(codes) == 0 {
codes = []OpCode{OpCode{'e', 0, 1, 0, 1}}
}
// Fixup leading and trailing groups if they show no changes.
if codes[0].Tag == 'e' {
c := codes[0]
i1, i2, j1, j2 := c.I1, c.I2, c.J1, c.J2
codes[0] = OpCode{c.Tag, max(i1, i2-n), i2, max(j1, j2-n), j2}
}
if codes[len(codes)-1].Tag == 'e' {
c := codes[len(codes)-1]
i1, i2, j1, j2 := c.I1, c.I2, c.J1, c.J2
codes[len(codes)-1] = OpCode{c.Tag, i1, min(i2, i1+n), j1, min(j2, j1+n)}
}
nn := n + n
groups := [][]OpCode{}
group := []OpCode{}
for _, c := range codes {
i1, i2, j1, j2 := c.I1, c.I2, c.J1, c.J2
// End the current group and start a new one whenever
// there is a large range with no changes.
if c.Tag == 'e' && i2-i1 > nn {
group = append(group, OpCode{c.Tag, i1, min(i2, i1+n),
j1, min(j2, j1+n)})
groups = append(groups, group)
group = []OpCode{}
i1, j1 = max(i1, i2-n), max(j1, j2-n)
}
group = append(group, OpCode{c.Tag, i1, i2, j1, j2})
}
if len(group) > 0 && !(len(group) == 1 && group[0].Tag == 'e') {
groups = append(groups, group)
}
return groups
}
// Return a measure of the sequences' similarity (float in [0,1]).
//
// Where T is the total number of elements in both sequences, and
// M is the number of matches, this is 2.0*M / T.
// Note that this is 1 if the sequences are identical, and 0 if
// they have nothing in common.
//
// .Ratio() is expensive to compute if you haven't already computed
// .GetMatchingBlocks() or .GetOpCodes(), in which case you may
// want to try .QuickRatio() or .RealQuickRation() first to get an
// upper bound.
func (m *SequenceMatcher) Ratio() float64 {
matches := 0
for _, m := range m.GetMatchingBlocks() {
matches += m.Size
}
return calculateRatio(matches, len(m.a)+len(m.b))
}
// Return an upper bound on ratio() relatively quickly.
//
// This isn't defined beyond that it is an upper bound on .Ratio(), and
// is faster to compute.
func (m *SequenceMatcher) QuickRatio() float64 {
// viewing a and b as multisets, set matches to the cardinality
// of their intersection; this counts the number of matches
// without regard to order, so is clearly an upper bound. We do
// so on hashes of the lines themselves, so this might even be
// greater due hash collisions incurring false positives, but
// we don't care because we want an upper bound anyway.
if m.fullBCount == nil {
m.fullBCount = map[lineHash]int{}
for _, s := range m.b {
h := _hash(s)
m.fullBCount[h] = m.fullBCount[h] + 1
}
}
// avail[x] is the number of times x appears in 'b' less the
// number of times we've seen it in 'a' so far ... kinda
avail := map[lineHash]int{}
matches := 0
for _, s := range m.a {
h := _hash(s)
n, ok := avail[h]
if !ok {
n = m.fullBCount[h]
}
avail[h] = n - 1
if n > 0 {
matches += 1
}
}
return calculateRatio(matches, len(m.a)+len(m.b))
}
// Return an upper bound on ratio() very quickly.
//
// This isn't defined beyond that it is an upper bound on .Ratio(), and
// is faster to compute than either .Ratio() or .QuickRatio().
func (m *SequenceMatcher) RealQuickRatio() float64 {
la, lb := len(m.a), len(m.b)
return calculateRatio(min(la, lb), la+lb)
}
func count_leading(line []byte, ch byte) (count int) {
// Return number of `ch` characters at the start of `line`.
count = 0
n := len(line)
for (count < n) && (line[count] == ch) {
count++
}
return count
}
type DiffLine struct {
Tag byte
Line []byte
}
func NewDiffLine(tag byte, line []byte) (l DiffLine) {
l = DiffLine{}
l.Tag = tag
l.Line = line
return l
}
type Differ struct {
Linejunk func([]byte) bool
Charjunk func([]byte) bool
}
func NewDiffer() *Differ {
return &Differ{}
}
var MINUS = []byte("-")
var SPACE = []byte(" ")
var PLUS = []byte("+")
var CARET = []byte("^")
func (d *Differ) Compare(a [][]byte, b [][]byte) (diffs [][]byte, err error) {
// Compare two sequences of lines; generate the resulting delta.
// Each sequence must contain individual single-line strings ending with
// newlines. Such sequences can be obtained from the `readlines()` method
// of file-like objects. The delta generated also consists of newline-
// terminated strings, ready to be printed as-is via the writeline()
// method of a file-like object.
diffs = [][]byte{}
cruncher := NewMatcherWithJunk(a, b, true, d.Linejunk)
opcodes := cruncher.GetOpCodes()
for _, current := range opcodes {
alo := current.I1
ahi := current.I2
blo := current.J1
bhi := current.J2
var g [][]byte
if current.Tag == 'r' {
g, _ = d.FancyReplace(a, alo, ahi, b, blo, bhi)
} else if current.Tag == 'd' {
g = d.Dump(MINUS, a, alo, ahi)
} else if current.Tag == 'i' {
g = d.Dump(PLUS, b, blo, bhi)
} else if current.Tag == 'e' {
g = d.Dump(SPACE, a, alo, ahi)
} else {
return nil, errors.New(fmt.Sprintf("unknown tag %q", current.Tag))
}
diffs = append(diffs, g...)
}
return diffs, nil
}
func (d *Differ) StructuredDump(tag byte, x [][]byte, low int, high int) (out []DiffLine) {
size := high - low
out = make([]DiffLine, size)
for i := 0; i < size; i++ {
out[i] = NewDiffLine(tag, x[i + low])
}
return out
}
func (d *Differ) Dump(tag []byte, x [][]byte, low int, high int) (out [][]byte) {
// Generate comparison results for a same-tagged range.
sout := d.StructuredDump(tag[0], x, low, high)
out = make([][]byte, len(sout))
var bld bytes.Buffer
bld.Grow(1024)
for i, line := range sout {
bld.Reset()
bld.WriteByte(line.Tag)
bld.Write(SPACE)
bld.Write(line.Line)
out[i] = append(out[i], bld.Bytes()...)
}
return out
}
func (d *Differ) PlainReplace(a [][]byte, alo int, ahi int, b [][]byte, blo int, bhi int) (out [][]byte, err error) {
if !(alo < ahi) || !(blo < bhi) { // assertion
return nil, errors.New("low greater than or equal to high")
}
// dump the shorter block first -- reduces the burden on short-term
// memory if the blocks are of very different sizes
if bhi-blo < ahi-alo {
out = d.Dump(PLUS, b, blo, bhi)
out = append(out, d.Dump(MINUS, a, alo, ahi)...)
} else {
out = d.Dump(MINUS, a, alo, ahi)
out = append(out, d.Dump(PLUS, b, blo, bhi)...)
}
return out, nil
}
func (d *Differ) FancyReplace(a [][]byte, alo int, ahi int, b [][]byte, blo int, bhi int) (out [][]byte, err error) {
// When replacing one block of lines with another, search the blocks
// for *similar* lines; the best-matching pair (if any) is used as a
// synch point, and intraline difference marking is done on the
// similar pair. Lots of work, but often worth it.
// don't synch up unless the lines have a similarity score of at
// least cutoff; best_ratio tracks the best score seen so far
best_ratio := 0.74
cutoff := 0.75
cruncher := NewMatcherWithJunk(a, b, true, d.Charjunk)
eqi := -1 // 1st indices of equal lines (if any)
eqj := -1
out = [][]byte{}
// search for the pair that matches best without being identical
// (identical lines must be junk lines, & we don't want to synch up
// on junk -- unless we have to)
var best_i, best_j int
for j := blo; j < bhi; j++ {
bj := b[j]
cruncher.SetSeq2(listifyString(bj))
for i := alo; i < ahi; i++ {
ai := a[i]
if bytes.Equal(ai, bj) {
if eqi == -1 {
eqi = i
eqj = j
}
continue
}
cruncher.SetSeq1(listifyString(ai))
// computing similarity is expensive, so use the quick
// upper bounds first -- have seen this speed up messy
// compares by a factor of 3.
// note that ratio() is only expensive to compute the first
// time it's called on a sequence pair; the expensive part
// of the computation is cached by cruncher
if cruncher.RealQuickRatio() > best_ratio &&
cruncher.QuickRatio() > best_ratio &&
cruncher.Ratio() > best_ratio {
best_ratio = cruncher.Ratio()
best_i = i
best_j = j
}
}
}
if best_ratio < cutoff {
// no non-identical "pretty close" pair
if eqi == -1 {
// no identical pair either -- treat it as a straight replace
out, _ = d.PlainReplace(a, alo, ahi, b, blo, bhi)
return out, nil
}
// no close pair, but an identical pair -- synch up on that
best_i = eqi
best_j = eqj
best_ratio = 1.0
} else {
// there's a close pair, so forget the identical pair (if any)
eqi = -1
}
// a[best_i] very similar to b[best_j]; eqi is None iff they're not
// identical
// pump out diffs from before the synch point
out = append(out, d.fancyHelper(a, alo, best_i, b, blo, best_j)...)
// do intraline marking on the synch pair
aelt, belt := a[best_i], b[best_j]
if eqi == -1 {
// pump out a '-', '?', '+', '?' quad for the synched lines
var atags, btags []byte
cruncher.SetSeqs(listifyString(aelt), listifyString(belt))
opcodes := cruncher.GetOpCodes()
for _, current := range opcodes {
ai1 := current.I1
ai2 := current.I2
bj1 := current.J1
bj2 := current.J2
la, lb := ai2-ai1, bj2-bj1
if current.Tag == 'r' {
atags = append(atags, bytes.Repeat(CARET, la)...)
btags = append(btags, bytes.Repeat(CARET, lb)...)
} else if current.Tag == 'd' {
atags = append(atags, bytes.Repeat(MINUS, la)...)
} else if current.Tag == 'i' {
btags = append(btags, bytes.Repeat(PLUS, lb)...)
} else if current.Tag == 'e' {
atags = append(atags, bytes.Repeat(SPACE, la)...)
btags = append(btags, bytes.Repeat(SPACE, lb)...)
} else {
return nil, errors.New(fmt.Sprintf("unknown tag %q",
current.Tag))
}
}
out = append(out, d.QFormat(aelt, belt, atags, btags)...)
} else {
// the synch pair is identical
out = append(out, append([]byte{' ', ' '}, aelt...))
}
// pump out diffs from after the synch point
out = append(out, d.fancyHelper(a, best_i+1, ahi, b, best_j+1, bhi)...)
return out, nil
}
func (d *Differ) fancyHelper(a [][]byte, alo int, ahi int, b [][]byte, blo int, bhi int) (out [][]byte) {
if alo < ahi {
if blo < bhi {
out, _ = d.FancyReplace(a, alo, ahi, b, blo, bhi)
} else {
out = d.Dump(MINUS, a, alo, ahi)
}
} else if blo < bhi {
out = d.Dump(PLUS, b, blo, bhi)
} else {
out = [][]byte{}
}
return out
}
func (d *Differ) QFormat(aline []byte, bline []byte, atags []byte, btags []byte) (out [][]byte) {
// Format "?" output and deal with leading tabs.
// Can hurt, but will probably help most of the time.
common := min(count_leading(aline, '\t'), count_leading(bline, '\t'))
common = min(common, count_leading(atags[:common], ' '))
common = min(common, count_leading(btags[:common], ' '))
atags = bytes.TrimRightFunc(atags[common:], unicode.IsSpace)
btags = bytes.TrimRightFunc(btags[common:], unicode.IsSpace)
out = [][]byte{append([]byte("- "), aline...)}
if len(atags) > 0 {
t := make([]byte, 0, len(atags) + common + 3)
t = append(t, []byte("? ")...)
for i := 0; i < common; i++ {
t = append(t, byte('\t'))
}
t = append(t, atags...)
t = append(t, byte('\n'))
out = append(out, t)
}
out = append(out, append([]byte("+ "), bline...))
if len(btags) > 0 {
t := make([]byte, 0, len(btags) + common + 3)
t = append(t, []byte("? ")...)
for i := 0; i < common; i++ {
t = append(t, byte('\t'))
}
t = append(t, btags...)
t = append(t, byte('\n'))
out = append(out, t)
}
return out
}
// Convert range to the "ed" format
func formatRangeUnified(start, stop int) []byte {
// Per the diff spec at http://www.unix.org/single_unix_specification/
beginning := start + 1 // lines start numbering with one
length := stop - start
if length == 1 {
return []byte(fmt.Sprintf("%d", beginning))
}
if length == 0 {
beginning -= 1 // empty ranges begin at line just before the range
}
return []byte(fmt.Sprintf("%d,%d", beginning, length))
}
// Unified diff parameters
type UnifiedDiff struct {
A [][]byte // First sequence lines
FromFile string // First file name
FromDate string // First file time
B [][]byte // Second sequence lines
ToFile string // Second file name
ToDate string // Second file time
Eol []byte // Headers end of line, defaults to LF
Context int // Number of context lines
}
// Compare two sequences of lines; generate the delta as a unified diff.
//
// Unified diffs are a compact way of showing line changes and a few
// lines of context. The number of context lines is set by 'n' which
// defaults to three.
//
// By default, the diff control lines (those with ---, +++, or @@) are
// created with a trailing newline. This is helpful so that inputs
// created from file.readlines() result in diffs that are suitable for
// file.writelines() since both the inputs and outputs have trailing
// newlines.
//
// For inputs that do not have trailing newlines, set the lineterm
// argument to "" so that the output will be uniformly newline free.
//
// The unidiff format normally has a header for filenames and modification
// times. Any or all of these may be specified using strings for
// 'fromfile', 'tofile', 'fromfiledate', and 'tofiledate'.
// The modification times are normally expressed in the ISO 8601 format.
func WriteUnifiedDiff(writer io.Writer, diff UnifiedDiff) error {
//buf := bufio.NewWriter(writer)
//defer buf.Flush()
var bld strings.Builder
bld.Reset()
wf := func(format string, args ...interface{}) error {
_, err := fmt.Fprintf(&bld, format, args...)
return err
}
ws := func(s []byte) error {
_, err := bld.Write(s)
return err
}
if len(diff.Eol) == 0 {
diff.Eol = []byte("\n")
}
started := false
m := NewMatcher(diff.A, diff.B)
for _, g := range m.GetGroupedOpCodes(diff.Context) {
if !started {
started = true
fromDate := ""
if len(diff.FromDate) > 0 {
fromDate = "\t" + diff.FromDate
}
toDate := ""
if len(diff.ToDate) > 0 {
toDate = "\t" + diff.ToDate
}
if diff.FromFile != "" || diff.ToFile != "" {
err := wf("--- %s%s%s", diff.FromFile, fromDate, diff.Eol)
if err != nil {
return err
}
err = wf("+++ %s%s%s", diff.ToFile, toDate, diff.Eol)
if err != nil {
return err
}
}
}
first, last := g[0], g[len(g)-1]
range1 := formatRangeUnified(first.I1, last.I2)
range2 := formatRangeUnified(first.J1, last.J2)
if err := wf("@@ -%s +%s @@%s", range1, range2, diff.Eol); err != nil {
return err
}
for _, c := range g {
i1, i2, j1, j2 := c.I1, c.I2, c.J1, c.J2
if c.Tag == 'e' {
for _, line := range diff.A[i1:i2] {
if err := ws(SPACE); err != nil {
return err
}
if err := ws(line); err != nil {
return err
}
}
continue
}
if c.Tag == 'r' || c.Tag == 'd' {
for _, line := range diff.A[i1:i2] {
if err := ws(MINUS); err != nil {
return err
}
if err := ws(line); err != nil {
return err
}
}
}
if c.Tag == 'r' || c.Tag == 'i' {
for _, line := range diff.B[j1:j2] {
if err := ws(PLUS); err != nil {
return err
}
if err := ws(line); err != nil {
return err
}
}
}
}
}
buf := bufio.NewWriter(writer)
buf.WriteString(bld.String())
buf.Flush()
return nil
}
// Like WriteUnifiedDiff but returns the diff a []byte.
func GetUnifiedDiffString(diff UnifiedDiff) ([]byte, error) {
w := &bytes.Buffer{}
err := WriteUnifiedDiff(w, diff)
return []byte(w.Bytes()), err
}
// Convert range to the "ed" format.
func formatRangeContext(start, stop int) []byte {
// Per the diff spec at http://www.unix.org/single_unix_specification/
beginning := start + 1 // lines start numbering with one
length := stop - start
if length == 0 {
beginning -= 1 // empty ranges begin at line just before the range
}
if length <= 1 {
return []byte(fmt.Sprintf("%d", beginning))
}
return []byte(fmt.Sprintf("%d,%d", beginning, beginning+length-1))
}
type ContextDiff UnifiedDiff
// Compare two sequences of lines; generate the delta as a context diff.
//
// Context diffs are a compact way of showing line changes and a few
// lines of context. The number of context lines is set by diff.Context
// which defaults to three.
//
// By default, the diff control lines (those with *** or ---) are
// created with a trailing newline.
//
// For inputs that do not have trailing newlines, set the diff.Eol
// argument to "" so that the output will be uniformly newline free.
//
// The context diff format normally has a header for filenames and
// modification times. Any or all of these may be specified using
// strings for diff.FromFile, diff.ToFile, diff.FromDate, diff.ToDate.
// The modification times are normally expressed in the ISO 8601 format.
// If not specified, the strings default to blanks.
func WriteContextDiff(writer io.Writer, diff ContextDiff) error {
buf := bufio.NewWriter(writer)
defer buf.Flush()
var diffErr error
wf := func(format string, args ...interface{}) {
_, err := buf.WriteString(fmt.Sprintf(format, args...))
if diffErr == nil && err != nil {
diffErr = err
}
}
ws := func(s []byte) {
_, err := buf.Write(s)
if diffErr == nil && err != nil {
diffErr = err
}
}
if len(diff.Eol) == 0 {
diff.Eol = []byte("\n")
}
prefix := map[byte][]byte{
'i': []byte("+ "),
'd': []byte("- "),
'r': []byte("! "),
'e': []byte(" "),
}
started := false
m := NewMatcher(diff.A, diff.B)
for _, g := range m.GetGroupedOpCodes(diff.Context) {
if !started {
started = true
fromDate := ""
if len(diff.FromDate) > 0 {
fromDate = "\t" + diff.FromDate
}
toDate := ""
if len(diff.ToDate) > 0 {
toDate = "\t" + diff.ToDate
}
if diff.FromFile != "" || diff.ToFile != "" {
wf("*** %s%s%s", diff.FromFile, fromDate, diff.Eol)
wf("--- %s%s%s", diff.ToFile, toDate, diff.Eol)
}
}
first, last := g[0], g[len(g)-1]
ws([]byte("***************"))
ws(diff.Eol)
range1 := formatRangeContext(first.I1, last.I2)
wf("*** %s ****%s", range1, diff.Eol)
for _, c := range g {
if c.Tag == 'r' || c.Tag == 'd' {
for _, cc := range g {
if cc.Tag == 'i' {
continue
}
for _, line := range diff.A[cc.I1:cc.I2] {
ws(prefix[cc.Tag])
ws(line)
}
}
break
}
}
range2 := formatRangeContext(first.J1, last.J2)
wf("--- %s ----%s", range2, diff.Eol)
for _, c := range g {
if c.Tag == 'r' || c.Tag == 'i' {
for _, cc := range g {
if cc.Tag == 'd' {
continue
}
for _, line := range diff.B[cc.J1:cc.J2] {
ws(prefix[cc.Tag])
ws(line)
}
}
break
}
}
}
return diffErr
}
// Like WriteContextDiff but returns the diff a []byte.
func GetContextDiffString(diff ContextDiff) ([]byte, error) {
w := &bytes.Buffer{}
err := WriteContextDiff(w, diff)
return []byte(w.Bytes()), err
}
// Split a []byte on "\n" while preserving them. The output can be used
// as input for UnifiedDiff and ContextDiff structures.
func SplitLines(s []byte) [][]byte {
lines := bytes.SplitAfter(s, []byte("\n"))
lines[len(lines)-1] = append(lines[len(lines)-1], '\n')
return lines
}
go-difflib-1.2.0/difflib/bytes/bytes_test.go 0000664 0000000 0000000 00000041650 13660101765 0020770 0 ustar 00root root 0000000 0000000 package bytes
import (
"bytes"
"fmt"
"math"
"reflect"
"runtime"
"strings"
"testing"
"sort"
"../tester"
)
func assertAlmostEqual(t *testing.T, a, b float64, places int) {
if math.Abs(a-b) > math.Pow10(-places) {
t.Errorf("%.7f != %.7f", a, b)
}
}
func assertEqual(t *testing.T, a, b interface{}) {
if !reflect.DeepEqual(a, b) {
t.Errorf("%v != %v", a, b)
}
}
func splitChars(s string) [][]byte {
chars := make([][]byte, 0, len(s))
// Assume ASCII inputs
for i := 0; i != len(s); i++ {
chars = append(chars, []byte{s[i]})
}
return chars
}
func stringsToBytes(in ...string) (out [][]byte) {
out = make([][]byte, len(in))
for i, s := range(in) {
out[i] = []byte(s)
}
return
}
func bytesToStrings(in ...[]byte) (out []string) {
out = make([]string, len(in))
for i, s := range(in) {
out[i] = string(s)
}
return
}
func TestlistifyString(t *testing.T) {
lst := listifyString([]byte("qwerty"))
if reflect.DeepEqual(lst, splitChars("qwerty")) != true {
t.Fatal("listifyString failure:", lst)
}
}
func TestSequenceMatcherRatio(t *testing.T) {
s := NewMatcher(splitChars("abcd"), splitChars("bcde"))
assertEqual(t, s.Ratio(), 0.75)
assertEqual(t, s.QuickRatio(), 0.75)
assertEqual(t, s.RealQuickRatio(), 1.0)
}
func TestGetOptCodes(t *testing.T) {
a := "qabxcd"
b := "abycdf"
s := NewMatcher(splitChars(a), splitChars(b))
w := &bytes.Buffer{}
for _, op := range s.GetOpCodes() {
fmt.Fprintf(w, "%s a[%d:%d], (%s) b[%d:%d] (%s)\n", string(op.Tag),
op.I1, op.I2, a[op.I1:op.I2], op.J1, op.J2, b[op.J1:op.J2])
}
result := string(w.Bytes())
expected := `d a[0:1], (q) b[0:0] ()
e a[1:3], (ab) b[0:2] (ab)
r a[3:4], (x) b[2:3] (y)
e a[4:6], (cd) b[3:5] (cd)
i a[6:6], () b[5:6] (f)
`
if expected != result {
t.Errorf("unexpected op codes: \n%s", result)
}
}
func TestGroupedOpCodes(t *testing.T) {
a := [][]byte{}
for i := 0; i != 39; i++ {
a = append(a, []byte(fmt.Sprintf("%02d", i)))
}
b := [][]byte{}
b = append(b, a[:8]...)
b = append(b, []byte(" i"))
b = append(b, a[8:19]...)
b = append(b, []byte(" x"))
b = append(b, a[20:22]...)
b = append(b, a[27:34]...)
b = append(b, []byte(" y"))
b = append(b, a[35:]...)
s := NewMatcher(a, b)
w := &bytes.Buffer{}
for _, g := range s.GetGroupedOpCodes(-1) {
fmt.Fprintf(w, "group\n")
for _, op := range g {
fmt.Fprintf(w, " %s, %d, %d, %d, %d\n", string(op.Tag),
op.I1, op.I2, op.J1, op.J2)
}
}
result := string(w.Bytes())
expected := `group
e, 5, 8, 5, 8
i, 8, 8, 8, 9
e, 8, 11, 9, 12
group
e, 16, 19, 17, 20
r, 19, 20, 20, 21
e, 20, 22, 21, 23
d, 22, 27, 23, 23
e, 27, 30, 23, 26
group
e, 31, 34, 27, 30
r, 34, 35, 30, 31
e, 35, 38, 31, 34
`
if expected != result {
t.Errorf("unexpected op codes: \n%s", result)
}
}
func ExampleGetUnifiedDiffCode() {
a := `one
two
three
four
fmt.Printf("%s,%T",a,b)`
b := `zero
one
three
four`
diff := UnifiedDiff{
A: SplitLines([]byte(a)),
B: SplitLines([]byte(b)),
FromFile: "Original",
FromDate: "2005-01-26 23:30:50",
ToFile: "Current",
ToDate: "2010-04-02 10:20:52",
Context: 3,
}
result, _ := GetUnifiedDiffString(diff)
fmt.Println(strings.Replace(string(result), "\t", " ", -1))
// Output:
// --- Original 2005-01-26 23:30:50
// +++ Current 2010-04-02 10:20:52
// @@ -1,5 +1,4 @@
// +zero
// one
// -two
// three
// four
// -fmt.Printf("%s,%T",a,b)
}
func ExampleGetContextDiffCode() {
a := `one
two
three
four
fmt.Printf("%s,%T",a,b)`
b := `zero
one
tree
four`
diff := ContextDiff{
A: SplitLines([]byte(a)),
B: SplitLines([]byte(b)),
FromFile: "Original",
ToFile: "Current",
Context: 3,
Eol: []byte{'\n'},
}
result, _ := GetContextDiffString(diff)
fmt.Print(strings.Replace(string(result), "\t", " ", -1))
// Output:
// *** Original
// --- Current
// ***************
// *** 1,5 ****
// one
// ! two
// ! three
// four
// - fmt.Printf("%s,%T",a,b)
// --- 1,4 ----
// + zero
// one
// ! tree
// four
}
func ExampleGetContextDiffString() {
a := `one
two
three
four`
b := `zero
one
tree
four`
diff := ContextDiff{
A: SplitLines([]byte(a)),
B: SplitLines([]byte(b)),
FromFile: "Original",
ToFile: "Current",
Context: 3,
Eol: []byte{'\n'},
}
result, _ := GetContextDiffString(diff)
fmt.Printf(strings.Replace(string(result), "\t", " ", -1))
// Output:
// *** Original
// --- Current
// ***************
// *** 1,4 ****
// one
// ! two
// ! three
// four
// --- 1,4 ----
// + zero
// one
// ! tree
// four
}
func rep(s string, count int) string {
return strings.Repeat(s, count)
}
func getall(b2j *B2J, lt lineType) [][]byte {
result := []int{}
for _, slots := range b2j.store {
for _, slot := range slots {
slt := lineNORMAL
if len(slot) == 2 && slot[1] < 0 {
slt = lineType(slot[1])
}
if lt == slt {
result = append(result, slot[0])
}
}
}
sort.Ints(result)
lines := make([][]byte, len(result))
for i, lineno := range result {
lines[i] = b2j.b[lineno]
}
return lines
}
func TestWithAsciiOneInsert(t *testing.T) {
sm := NewMatcher(splitChars(rep("b", 100)),
splitChars("a"+rep("b", 100)))
assertAlmostEqual(t, sm.Ratio(), 0.995, 3)
assertEqual(t, sm.GetOpCodes(),
[]OpCode{{'i', 0, 0, 0, 1}, {'e', 0, 100, 1, 101}})
assertEqual(t, len(getall(&sm.b2j, linePOPULAR)), 0)
sm = NewMatcher(splitChars(rep("b", 100)),
splitChars(rep("b", 50)+"a"+rep("b", 50)))
assertAlmostEqual(t, sm.Ratio(), 0.995, 3)
assertEqual(t, sm.GetOpCodes(),
[]OpCode{{'e', 0, 50, 0, 50}, {'i', 50, 50, 50, 51}, {'e', 50, 100, 51, 101}})
assertEqual(t, len(getall(&sm.b2j, linePOPULAR)), 0)
}
func TestWithAsciiOnDelete(t *testing.T) {
sm := NewMatcher(splitChars(rep("a", 40)+"c"+rep("b", 40)),
splitChars(rep("a", 40)+rep("b", 40)))
assertAlmostEqual(t, sm.Ratio(), 0.994, 3)
assertEqual(t, sm.GetOpCodes(),
[]OpCode{{'e', 0, 40, 0, 40}, {'d', 40, 41, 40, 40}, {'e', 41, 81, 40, 80}})
}
func TestWithAsciiBJunk(t *testing.T) {
isJunk := func(s []byte) bool {
return len(s) == 1 && s[0] == ' '
}
sm := NewMatcherWithJunk(splitChars(rep("a", 40)+rep("b", 40)),
splitChars(rep("a", 44)+rep("b", 40)), true, isJunk)
assertEqual(t, getall(&sm.b2j, lineJUNK), [][]byte{})
sm = NewMatcherWithJunk(splitChars(rep("a", 40)+rep("b", 40)),
splitChars(rep("a", 44)+rep("b", 40)+rep(" ", 20)), false, isJunk)
assertEqual(t, getall(&sm.b2j, lineJUNK), [][]byte{SPACE})
isJunk = func(s []byte) bool {
return len(s) == 1 && (s[0] == ' ' || s[0] == 'b')
}
sm = NewMatcherWithJunk(splitChars(rep("a", 40)+rep("b", 40)),
splitChars(rep("a", 44)+rep("b", 40)+rep(" ", 20)), false, isJunk)
assertEqual(t, getall(&sm.b2j, lineJUNK), [][]byte{[]byte{'b'}, SPACE})
}
func TestSFBugsRatioForNullSeqn(t *testing.T) {
sm := NewMatcher(nil, nil)
assertEqual(t, sm.Ratio(), 1.0)
assertEqual(t, sm.QuickRatio(), 1.0)
assertEqual(t, sm.RealQuickRatio(), 1.0)
}
func TestSFBugsComparingEmptyLists(t *testing.T) {
groups := NewMatcher(nil, nil).GetGroupedOpCodes(-1)
assertEqual(t, len(groups), 0)
diff := UnifiedDiff{
FromFile: "Original",
ToFile: "Current",
Context: 3,
}
result, err := GetUnifiedDiffString(diff)
assertEqual(t, err, nil)
assertEqual(t, string(result), "")
}
func TestOutputFormatRangeFormatUnified(t *testing.T) {
// Per the diff spec at http://www.unix.org/single_unix_specification/
//
// Each field shall be of the form:
// %1d", if the range contains exactly one line,
// and:
// "%1d,%1d", , otherwise.
// If a range is empty, its beginning line number shall be the number of
// the line just before the range, or 0 if the empty range starts the file.
fmt := formatRangeUnified
fm := func (a, b int) string { return string(fmt(a,b)) }
assertEqual(t, fm(3, 3), "3,0")
assertEqual(t, fm(3, 4), "4")
assertEqual(t, fm(3, 5), "4,2")
assertEqual(t, fm(3, 6), "4,3")
assertEqual(t, fm(0, 0), "0,0")
}
func TestOutputFormatRangeFormatContext(t *testing.T) {
// Per the diff spec at http://www.unix.org/single_unix_specification/
//
// The range of lines in file1 shall be written in the following format
// if the range contains two or more lines:
// "*** %d,%d ****\n", ,
// and the following format otherwise:
// "*** %d ****\n",
// The ending line number of an empty range shall be the number of the preceding line,
// or 0 if the range is at the start of the file.
//
// Next, the range of lines in file2 shall be written in the following format
// if the range contains two or more lines:
// "--- %d,%d ----\n", ,
// and the following format otherwise:
// "--- %d ----\n",
fmt := formatRangeContext
fm := func (a, b int) string { return string(fmt(a,b)) }
assertEqual(t, fm(3, 3), "3")
assertEqual(t, fm(3, 4), "4")
assertEqual(t, fm(3, 5), "4,5")
assertEqual(t, fm(3, 6), "4,6")
assertEqual(t, fm(0, 0), "0")
}
func TestOutputFormatTabDelimiter(t *testing.T) {
diff := UnifiedDiff{
A: splitChars("one"),
B: splitChars("two"),
FromFile: "Original",
FromDate: "2005-01-26 23:30:50",
ToFile: "Current",
ToDate: "2010-04-12 10:20:52",
Eol: []byte{'\n'},
}
ud, err := GetUnifiedDiffString(diff)
assertEqual(t, err, nil)
assertEqual(t, SplitLines(ud)[:2], stringsToBytes(
"--- Original\t2005-01-26 23:30:50\n",
"+++ Current\t2010-04-12 10:20:52\n",
))
cd, err := GetContextDiffString(ContextDiff(diff))
assertEqual(t, err, nil)
assertEqual(t, SplitLines(cd)[:2], stringsToBytes(
"*** Original\t2005-01-26 23:30:50\n",
"--- Current\t2010-04-12 10:20:52\n",
))
}
func TestOutputFormatNoTrailingTabOnEmptyFiledate(t *testing.T) {
diff := UnifiedDiff{
A: splitChars("one"),
B: splitChars("two"),
FromFile: "Original",
ToFile: "Current",
Eol: []byte{'\n'},
}
ud, err := GetUnifiedDiffString(diff)
assertEqual(t, err, nil)
assertEqual(t, SplitLines(ud)[:2], stringsToBytes("--- Original\n", "+++ Current\n"))
cd, err := GetContextDiffString(ContextDiff(diff))
assertEqual(t, err, nil)
assertEqual(t, SplitLines(cd)[:2], stringsToBytes("*** Original\n", "--- Current\n"))
}
func TestOmitFilenames(t *testing.T) {
diff := UnifiedDiff{
A: SplitLines([]byte("o\nn\ne\n")),
B: SplitLines([]byte("t\nw\no\n")),
Eol: []byte{'\n'},
}
ud, err := GetUnifiedDiffString(diff)
assertEqual(t, err, nil)
assertEqual(t, SplitLines(ud), stringsToBytes(
"@@ -0,0 +1,2 @@\n",
"+t\n",
"+w\n",
"@@ -2,2 +3,0 @@\n",
"-n\n",
"-e\n",
"\n",
))
cd, err := GetContextDiffString(ContextDiff(diff))
assertEqual(t, err, nil)
assertEqual(t, SplitLines(cd), stringsToBytes(
"***************\n",
"*** 0 ****\n",
"--- 1,2 ----\n",
"+ t\n",
"+ w\n",
"***************\n",
"*** 2,3 ****\n",
"- n\n",
"- e\n",
"--- 3 ----\n",
"\n",
))
}
func TestSplitLines(t *testing.T) {
allTests := []struct {
input string
want [][]byte
}{
{"foo", stringsToBytes("foo\n")},
{"foo\nbar", stringsToBytes("foo\n", "bar\n")},
{"foo\nbar\n", stringsToBytes("foo\n", "bar\n", "\n")},
}
for _, test := range allTests {
assertEqual(t, SplitLines([]byte(test.input)), test.want)
}
}
func benchmarkSplitLines(b *testing.B, count int) {
str := bytes.Repeat([]byte("foo\n"), count)
b.ResetTimer()
n := 0
for i := 0; i < b.N; i++ {
n += len(SplitLines(str))
}
}
func BenchmarkSplitLines100(b *testing.B) {
benchmarkSplitLines(b, 100)
}
func BenchmarkSplitLines10000(b *testing.B) {
benchmarkSplitLines(b, 10000)
}
func prepareFilesToDiff(count, seed int) (As, Bs [][][]byte) {
defer runtime.GC()
aux := func () { // to ensure temp variables go out of scope
stringsA, stringsB := tester.PrepareStringsToDiff(count, seed)
As = make([][][]byte, len(stringsA))
Bs = make([][][]byte, len(stringsB))
for i := range As {
As[i] = stringsToBytes(stringsA[i]...)
Bs[i] = stringsToBytes(stringsB[i]...)
}
}
aux()
return
}
func BenchmarkDiffer(b *testing.B) {
A, B := prepareFilesToDiff(b.N, 0)
fmt.Printf("\nDiff length:")
b.ResetTimer()
differ := NewDiffer()
for i := range A {
var x [][]byte
for n := 0; n < 5; n++ {
x, _ = differ.Compare(A[i], B[i])
}
fmt.Printf(" %v", len(x))
}
fmt.Printf("\n")
}
func BenchmarkMatcher(b *testing.B) {
As, Bs := prepareFilesToDiff(b.N, 0)
fmt.Printf("\nOpcodes count:")
b.ResetTimer()
for i := range As {
var x []OpCode
for n := 0; n < 5; n++ {
sm := NewMatcher(As[i], Bs[i])
x = sm.GetOpCodes()
}
fmt.Printf(" %v", len(x))
}
fmt.Printf("\n")
}
func TestDifferCompare(t *testing.T) {
diff := NewDiffer()
// Test
aLst := stringsToBytes("foo\n", "bar\n", "baz\n")
bLst := stringsToBytes("foo\n", "bar1\n", "asdf\n", "baz\n")
out, err := diff.Compare(aLst, bLst)
if err != nil {
t.Fatal("Differ Compare() error:", err)
}
out2 := bytesToStrings(out...)
if reflect.DeepEqual(out2, []string{
" foo\n",
"- bar\n",
"+ bar1\n",
"? +\n",
"+ asdf\n",
" baz\n",
}) != true {
t.Fatal("Differ Compare failure:", out2)
}
}
func TestDifferStructuredDump(t *testing.T) {
diff := NewDiffer()
out := diff.StructuredDump('+',
stringsToBytes("foo", "bar", "baz", "quux", "qwerty"),
1, 3)
expected := []DiffLine{DiffLine{'+', []byte("bar")},
DiffLine{'+', []byte("baz")}}
if !reflect.DeepEqual(out, expected) {
t.Fatal("Differ StructuredDump failure:", out)
}
}
func TestDifferDump(t *testing.T) {
diff := NewDiffer()
out := diff.Dump(PLUS,
stringsToBytes("foo", "bar", "baz", "quux", "qwerty"),
1, 3)
out2 := bytesToStrings(out...)
if reflect.DeepEqual(out2, []string{"+ bar", "+ baz"}) != true {
t.Fatal("Differ Dump() failure:", out2)
}
}
func TestDifferPlainReplace(t *testing.T) {
diff := NewDiffer()
aLst := stringsToBytes("one\n", "two\n", "three\n", "four\n", "five\n")
bLst := stringsToBytes("one\n", "two2\n", "three\n", "extra\n")
// Test a then b
out, err := diff.PlainReplace(aLst, 1, 2, bLst, 1, 2)
if err != nil {
t.Fatal("Differ PlainReplace() error:", err)
}
out2 := bytesToStrings(out...)
if reflect.DeepEqual(out2, []string{"- two\n", "+ two2\n"}) != true {
t.Fatal("Differ PlainReplace() failure:", out2)
}
// Test b then a
out, err = diff.PlainReplace(aLst, 3, 5, bLst, 3, 4)
if err != nil {
t.Fatal("Differ PlainReplace() error:", err)
}
out2 = bytesToStrings(out...)
if reflect.DeepEqual(out2,
[]string{"+ extra\n", "- four\n", "- five\n"}) != true {
t.Fatal("Differ PlainReplace() failure:", out2)
}
}
func TestDifferFancyReplaceAndHelper(t *testing.T) {
diff := NewDiffer()
// Test identical sync point, both full
aLst := stringsToBytes("one\n", "asdf\n", "three\n")
bLst := stringsToBytes("one\n", "two2\n", "three\n")
out, err := diff.FancyReplace(aLst, 0, 3, bLst, 0, 3)
if err != nil {
t.Fatal("Differ FancyReplace() error:", err)
}
out2 := bytesToStrings(out...)
if reflect.DeepEqual(out2,
[]string{" one\n", "- asdf\n", "+ two2\n", " three\n"}) != true {
t.Fatal("Differ FancyReplace() failure:", out2)
}
// Test close sync point, both full
aLst = stringsToBytes("one\n", "two123456\n", "asdf\n", "three\n")
bLst = stringsToBytes("one\n", "two123457\n", "qwerty\n", "three\n")
out, err = diff.FancyReplace(aLst, 1, 3, bLst, 1, 3)
if err != nil {
t.Fatal("Differ FancyReplace() error:", err)
}
out2 = bytesToStrings(out...)
if reflect.DeepEqual(out2, []string{
"- two123456\n",
"? ^\n",
"+ two123457\n",
"? ^\n",
"- asdf\n",
"+ qwerty\n",
}) != true {
t.Fatal("Differ FancyReplace() failure:", out2)
}
// Test no identical no close
aLst = stringsToBytes("one\n", "asdf\n", "three\n")
bLst = stringsToBytes("one\n", "qwerty\n", "three\n")
out, err = diff.FancyReplace(aLst, 1, 2, bLst, 1, 2)
if err != nil {
t.Fatal("Differ FancyReplace() error:", err)
}
out2 = bytesToStrings(out...)
if reflect.DeepEqual(out2, []string{
"- asdf\n",
"+ qwerty\n",
}) != true {
t.Fatal("Differ FancyReplace() failure:", out2)
}
}
func TestDifferQFormat(t *testing.T) {
diff := NewDiffer()
aStr := []byte("\tfoo2bar\n")
aTag := []byte(" ^ ^")
bStr := []byte("\tfoo3baz\n")
bTag := []byte(" ^ ^")
out := diff.QFormat(aStr, bStr, aTag, bTag)
out2 := bytesToStrings(out...)
if reflect.DeepEqual(out2, []string{
"- \tfoo2bar\n",
"? \t ^ ^\n",
"+ \tfoo3baz\n",
"? \t ^ ^\n",
}) != true {
t.Fatal("Differ QFormat() failure:", out2)
}
}
func TestGetUnifiedDiffString(t *testing.T) {
A := []byte("one\ntwo\nthree\nfour\nfive\nsix\nseven\neight\nnine\nten\n")
B := []byte("one\ntwo\nthr33\nfour\nfive\nsix\nseven\neight\nnine\nten\n")
// Build diff
diff := UnifiedDiff{A: SplitLines(A),
FromFile: "file", FromDate: "then",
B: SplitLines(B),
ToFile: "tile", ToDate: "now", Eol: []byte{}, Context: 1}
// Run test
diffStr, err := GetUnifiedDiffString(diff)
if err != nil {
t.Fatal("GetUnifiedDiffString error:", err)
}
exp := []byte("--- file\tthen\n+++ tile\tnow\n@@ -2,3 +2,3 @@\n two\n-three\n+thr33\n four\n")
if !bytes.Equal(diffStr, exp) {
t.Fatal("GetUnifiedDiffString failure:", diffStr)
}
}
go-difflib-1.2.0/difflib/difflib.go 0000664 0000000 0000000 00000075004 13660101765 0017054 0 ustar 00root root 0000000 0000000 // Package difflib is a partial port of Python difflib module.
//
// It provides tools to compare sequences of strings and generate textual diffs.
//
// The following class and functions have been ported:
//
// - SequenceMatcher
//
// - unified_diff
//
// - context_diff
//
// Getting unified diffs was the main goal of the port. Keep in mind this code
// is mostly suitable to output text differences in a human friendly way, there
// are no guarantees generated diffs are consumable by patch(1).
package difflib
import (
"bufio"
"bytes"
"errors"
"fmt"
"io"
"strings"
"unicode"
)
func min(a, b int) int {
if a < b {
return a
}
return b
}
func max(a, b int) int {
if a > b {
return a
}
return b
}
func calculateRatio(matches, length int) float64 {
if length > 0 {
return 2.0 * float64(matches) / float64(length)
}
return 1.0
}
func listifyString(str string) (lst []string) {
lst = make([]string, len(str))
for i, c := range str {
lst[i] = string(c)
}
return lst
}
type Match struct {
A int
B int
Size int
}
type OpCode struct {
Tag byte
I1 int
I2 int
J1 int
J2 int
}
// SequenceMatcher compares sequence of strings. The basic
// algorithm predates, and is a little fancier than, an algorithm
// published in the late 1980's by Ratcliff and Obershelp under the
// hyperbolic name "gestalt pattern matching". The basic idea is to find
// the longest contiguous matching subsequence that contains no "junk"
// elements (R-O doesn't address junk). The same idea is then applied
// recursively to the pieces of the sequences to the left and to the right
// of the matching subsequence. This does not yield minimal edit
// sequences, but does tend to yield matches that "look right" to people.
//
// SequenceMatcher tries to compute a "human-friendly diff" between two
// sequences. Unlike e.g. UNIX(tm) diff, the fundamental notion is the
// longest *contiguous* & junk-free matching subsequence. That's what
// catches peoples' eyes. The Windows(tm) windiff has another interesting
// notion, pairing up elements that appear uniquely in each sequence.
// That, and the method here, appear to yield more intuitive difference
// reports than does diff. This method appears to be the least vulnerable
// to synching up on blocks of "junk lines", though (like blank lines in
// ordinary text files, or maybe "" lines in HTML files). That may be
// because this is the only method of the 3 that has a *concept* of
// "junk" .
//
// Timing: Basic R-O is cubic time worst case and quadratic time expected
// case. SequenceMatcher is quadratic time for the worst case and has
// expected-case behavior dependent in a complicated way on how many
// elements the sequences have in common; best case time is linear.
type SequenceMatcher struct {
a []string
b []string
b2j map[string][]int
IsJunk func(string) bool
autoJunk bool
bJunk map[string]bool
matchingBlocks []Match
fullBCount map[string]int
bPopular map[string]bool
opCodes []OpCode
}
func NewMatcher(a, b []string) *SequenceMatcher {
m := SequenceMatcher{autoJunk: true}
m.SetSeqs(a, b)
return &m
}
func NewMatcherWithJunk(a, b []string, autoJunk bool,
isJunk func(string) bool) *SequenceMatcher {
m := SequenceMatcher{IsJunk: isJunk, autoJunk: autoJunk}
m.SetSeqs(a, b)
return &m
}
// Set two sequences to be compared.
func (m *SequenceMatcher) SetSeqs(a, b []string) {
m.SetSeq1(a)
m.SetSeq2(b)
}
// Set the first sequence to be compared. The second sequence to be compared is
// not changed.
//
// SequenceMatcher computes and caches detailed information about the second
// sequence, so if you want to compare one sequence S against many sequences,
// use .SetSeq2(s) once and call .SetSeq1(x) repeatedly for each of the other
// sequences.
//
// See also SetSeqs() and SetSeq2().
func (m *SequenceMatcher) SetSeq1(a []string) {
if &a == &m.a {
return
}
m.a = a
m.matchingBlocks = nil
m.opCodes = nil
}
// Set the second sequence to be compared. The first sequence to be compared is
// not changed.
func (m *SequenceMatcher) SetSeq2(b []string) {
if &b == &m.b {
return
}
m.b = b
m.matchingBlocks = nil
m.opCodes = nil
m.fullBCount = nil
m.chainB()
}
func (m *SequenceMatcher) chainB() {
// Populate line -> index mapping
b2j := map[string][]int{}
junk := map[string]bool{}
popular := map[string]bool{}
ntest := len(m.b)
if m.autoJunk && ntest >= 200 {
ntest = ntest/100 + 1
}
for i, s := range m.b {
if !junk[s] {
if m.IsJunk != nil && m.IsJunk(s) {
junk[s] = true
} else if !popular[s] {
ids := append(b2j[s], i)
if len(ids) <= ntest {
b2j[s] = ids
} else {
delete(b2j, s)
popular[s] = true
}
}
}
}
m.b2j = b2j
m.bJunk = junk
m.bPopular = popular
}
func (m *SequenceMatcher) isBJunk(s string) bool {
_, ok := m.bJunk[s]
return ok
}
// Find longest matching block in a[alo:ahi] and b[blo:bhi].
//
// If IsJunk is not defined:
//
// Return (i,j,k) such that a[i:i+k] is equal to b[j:j+k], where
// alo <= i <= i+k <= ahi
// blo <= j <= j+k <= bhi
// and for all (i',j',k') meeting those conditions,
// k >= k'
// i <= i'
// and if i == i', j <= j'
//
// In other words, of all maximal matching blocks, return one that
// starts earliest in a, and of all those maximal matching blocks that
// start earliest in a, return the one that starts earliest in b.
//
// If IsJunk is defined, first the longest matching block is
// determined as above, but with the additional restriction that no
// junk element appears in the block. Then that block is extended as
// far as possible by matching (only) junk elements on both sides. So
// the resulting block never matches on junk except as identical junk
// happens to be adjacent to an "interesting" match.
//
// If no blocks match, return (alo, blo, 0).
func (m *SequenceMatcher) findLongestMatch(alo, ahi, blo, bhi int) Match {
// CAUTION: stripping common prefix or suffix would be incorrect.
// E.g.,
// ab
// acab
// Longest matching block is "ab", but if common prefix is
// stripped, it's "a" (tied with "b"). UNIX(tm) diff does so
// strip, so ends up claiming that ab is changed to acab by
// inserting "ca" in the middle. That's minimal but unintuitive:
// "it's obvious" that someone inserted "ac" at the front.
// Windiff ends up at the same place as diff, but by pairing up
// the unique 'b's and then matching the first two 'a's.
besti, bestj, bestsize := alo, blo, 0
// find longest junk-free match
// during an iteration of the loop, j2len[j] = length of longest
// junk-free match ending with a[i-1] and b[j]
N := bhi - blo
j2len := make([]int, N)
newj2len := make([]int, N)
var indices []int
for i := alo; i != ahi; i++ {
// look at all instances of a[i] in b; note that because
// b2j has no junk keys, the loop is skipped if a[i] is junk
newindices := m.b2j[m.a[i]]
for _, j := range newindices {
// a[i] matches b[j]
if j < blo {
continue
}
if j >= bhi {
break
}
k := 1
if j > blo {
k = j2len[j-1-blo] + 1
}
newj2len[j-blo] = k
if k > bestsize {
besti, bestj, bestsize = i-k+1, j-k+1, k
}
}
// j2len = newj2len, clear and reuse j2len as newj2len
for _, j := range indices {
if j < blo {
continue
}
if j >= bhi {
break
}
j2len[j-blo] = 0
}
indices = newindices
j2len, newj2len = newj2len, j2len
}
// Extend the best by non-junk elements on each end. In particular,
// "popular" non-junk elements aren't in b2j, which greatly speeds
// the inner loop above, but also means "the best" match so far
// doesn't contain any junk *or* popular non-junk elements.
for besti > alo && bestj > blo && !m.isBJunk(m.b[bestj-1]) &&
m.a[besti-1] == m.b[bestj-1] {
besti, bestj, bestsize = besti-1, bestj-1, bestsize+1
}
for besti+bestsize < ahi && bestj+bestsize < bhi &&
!m.isBJunk(m.b[bestj+bestsize]) &&
m.a[besti+bestsize] == m.b[bestj+bestsize] {
bestsize += 1
}
// Now that we have a wholly interesting match (albeit possibly
// empty!), we may as well suck up the matching junk on each
// side of it too. Can't think of a good reason not to, and it
// saves post-processing the (possibly considerable) expense of
// figuring out what to do with it. In the case of an empty
// interesting match, this is clearly the right thing to do,
// because no other kind of match is possible in the regions.
for besti > alo && bestj > blo && m.isBJunk(m.b[bestj-1]) &&
m.a[besti-1] == m.b[bestj-1] {
besti, bestj, bestsize = besti-1, bestj-1, bestsize+1
}
for besti+bestsize < ahi && bestj+bestsize < bhi &&
m.isBJunk(m.b[bestj+bestsize]) &&
m.a[besti+bestsize] == m.b[bestj+bestsize] {
bestsize += 1
}
return Match{A: besti, B: bestj, Size: bestsize}
}
// Return list of triples describing matching subsequences.
//
// Each triple is of the form (i, j, n), and means that
// a[i:i+n] == b[j:j+n]. The triples are monotonically increasing in
// i and in j. It's also guaranteed that if (i, j, n) and (i', j', n') are
// adjacent triples in the list, and the second is not the last triple in the
// list, then i+n != i' or j+n != j'. IOW, adjacent triples never describe
// adjacent equal blocks.
//
// The last triple is a dummy, (len(a), len(b), 0), and is the only
// triple with n==0.
func (m *SequenceMatcher) GetMatchingBlocks() []Match {
if m.matchingBlocks != nil {
return m.matchingBlocks
}
var matchBlocks func(alo, ahi, blo, bhi int, matched []Match) []Match
matchBlocks = func(alo, ahi, blo, bhi int, matched []Match) []Match {
match := m.findLongestMatch(alo, ahi, blo, bhi)
i, j, k := match.A, match.B, match.Size
if match.Size > 0 {
if alo < i && blo < j {
matched = matchBlocks(alo, i, blo, j, matched)
}
matched = append(matched, match)
if i+k < ahi && j+k < bhi {
matched = matchBlocks(i+k, ahi, j+k, bhi, matched)
}
}
return matched
}
matched := matchBlocks(0, len(m.a), 0, len(m.b), nil)
// It's possible that we have adjacent equal blocks in the
// matching_blocks list now.
nonAdjacent := []Match{}
i1, j1, k1 := 0, 0, 0
for _, b := range matched {
// Is this block adjacent to i1, j1, k1?
i2, j2, k2 := b.A, b.B, b.Size
if i1+k1 == i2 && j1+k1 == j2 {
// Yes, so collapse them -- this just increases the length of
// the first block by the length of the second, and the first
// block so lengthened remains the block to compare against.
k1 += k2
} else {
// Not adjacent. Remember the first block (k1==0 means it's
// the dummy we started with), and make the second block the
// new block to compare against.
if k1 > 0 {
nonAdjacent = append(nonAdjacent, Match{i1, j1, k1})
}
i1, j1, k1 = i2, j2, k2
}
}
if k1 > 0 {
nonAdjacent = append(nonAdjacent, Match{i1, j1, k1})
}
nonAdjacent = append(nonAdjacent, Match{len(m.a), len(m.b), 0})
m.matchingBlocks = nonAdjacent
return m.matchingBlocks
}
// Return list of 5-tuples describing how to turn a into b.
//
// Each tuple is of the form (tag, i1, i2, j1, j2). The first tuple
// has i1 == j1 == 0, and remaining tuples have i1 == the i2 from the
// tuple preceding it, and likewise for j1 == the previous j2.
//
// The tags are characters, with these meanings:
//
// 'r' (replace): a[i1:i2] should be replaced by b[j1:j2]
//
// 'd' (delete): a[i1:i2] should be deleted, j1==j2 in this case.
//
// 'i' (insert): b[j1:j2] should be inserted at a[i1:i1], i1==i2 in this case.
//
// 'e' (equal): a[i1:i2] == b[j1:j2]
func (m *SequenceMatcher) GetOpCodes() []OpCode {
if m.opCodes != nil {
return m.opCodes
}
i, j := 0, 0
matching := m.GetMatchingBlocks()
opCodes := make([]OpCode, 0, len(matching))
for _, m := range matching {
// invariant: we've pumped out correct diffs to change
// a[:i] into b[:j], and the next matching block is
// a[ai:ai+size] == b[bj:bj+size]. So we need to pump
// out a diff to change a[i:ai] into b[j:bj], pump out
// the matching block, and move (i,j) beyond the match
ai, bj, size := m.A, m.B, m.Size
tag := byte(0)
if i < ai && j < bj {
tag = 'r'
} else if i < ai {
tag = 'd'
} else if j < bj {
tag = 'i'
}
if tag > 0 {
opCodes = append(opCodes, OpCode{tag, i, ai, j, bj})
}
i, j = ai+size, bj+size
// the list of matching blocks is terminated by a
// sentinel with size 0
if size > 0 {
opCodes = append(opCodes, OpCode{'e', ai, i, bj, j})
}
}
m.opCodes = opCodes
return m.opCodes
}
// Isolate change clusters by eliminating ranges with no changes.
//
// Return a generator of groups with up to n lines of context.
// Each group is in the same format as returned by GetOpCodes().
func (m *SequenceMatcher) GetGroupedOpCodes(n int) [][]OpCode {
if n < 0 {
n = 3
}
codes := m.GetOpCodes()
if len(codes) == 0 {
codes = []OpCode{OpCode{'e', 0, 1, 0, 1}}
}
// Fixup leading and trailing groups if they show no changes.
if codes[0].Tag == 'e' {
c := codes[0]
i1, i2, j1, j2 := c.I1, c.I2, c.J1, c.J2
codes[0] = OpCode{c.Tag, max(i1, i2-n), i2, max(j1, j2-n), j2}
}
if codes[len(codes)-1].Tag == 'e' {
c := codes[len(codes)-1]
i1, i2, j1, j2 := c.I1, c.I2, c.J1, c.J2
codes[len(codes)-1] = OpCode{c.Tag, i1, min(i2, i1+n), j1, min(j2, j1+n)}
}
nn := n + n
groups := [][]OpCode{}
group := []OpCode{}
for _, c := range codes {
i1, i2, j1, j2 := c.I1, c.I2, c.J1, c.J2
// End the current group and start a new one whenever
// there is a large range with no changes.
if c.Tag == 'e' && i2-i1 > nn {
group = append(group, OpCode{c.Tag, i1, min(i2, i1+n),
j1, min(j2, j1+n)})
groups = append(groups, group)
group = []OpCode{}
i1, j1 = max(i1, i2-n), max(j1, j2-n)
}
group = append(group, OpCode{c.Tag, i1, i2, j1, j2})
}
if len(group) > 0 && !(len(group) == 1 && group[0].Tag == 'e') {
groups = append(groups, group)
}
return groups
}
// Return a measure of the sequences' similarity (float in [0,1]).
//
// Where T is the total number of elements in both sequences, and
// M is the number of matches, this is 2.0*M / T.
// Note that this is 1 if the sequences are identical, and 0 if
// they have nothing in common.
//
// .Ratio() is expensive to compute if you haven't already computed
// .GetMatchingBlocks() or .GetOpCodes(), in which case you may
// want to try .QuickRatio() or .RealQuickRation() first to get an
// upper bound.
func (m *SequenceMatcher) Ratio() float64 {
matches := 0
for _, m := range m.GetMatchingBlocks() {
matches += m.Size
}
return calculateRatio(matches, len(m.a)+len(m.b))
}
// Return an upper bound on ratio() relatively quickly.
//
// This isn't defined beyond that it is an upper bound on .Ratio(), and
// is faster to compute.
func (m *SequenceMatcher) QuickRatio() float64 {
// viewing a and b as multisets, set matches to the cardinality
// of their intersection; this counts the number of matches
// without regard to order, so is clearly an upper bound
if m.fullBCount == nil {
m.fullBCount = map[string]int{}
for _, s := range m.b {
m.fullBCount[s] = m.fullBCount[s] + 1
}
}
// avail[x] is the number of times x appears in 'b' less the
// number of times we've seen it in 'a' so far ... kinda
avail := map[string]int{}
matches := 0
for _, s := range m.a {
n, ok := avail[s]
if !ok {
n = m.fullBCount[s]
}
avail[s] = n - 1
if n > 0 {
matches += 1
}
}
return calculateRatio(matches, len(m.a)+len(m.b))
}
// Return an upper bound on ratio() very quickly.
//
// This isn't defined beyond that it is an upper bound on .Ratio(), and
// is faster to compute than either .Ratio() or .QuickRatio().
func (m *SequenceMatcher) RealQuickRatio() float64 {
la, lb := len(m.a), len(m.b)
return calculateRatio(min(la, lb), la+lb)
}
func count_leading(line string, ch byte) (count int) {
// Return number of `ch` characters at the start of `line`.
count = 0
n := len(line)
for (count < n) && (line[count] == ch) {
count++
}
return count
}
type DiffLine struct {
Tag byte
Line string
}
func NewDiffLine(tag byte, line string) (l DiffLine) {
l = DiffLine{}
l.Tag = tag
l.Line = line
return l
}
type Differ struct {
Linejunk func(string) bool
Charjunk func(string) bool
}
func NewDiffer() *Differ {
return &Differ{}
}
func (d *Differ) Compare(a []string, b []string) (diffs []string, err error) {
// Compare two sequences of lines; generate the resulting delta.
// Each sequence must contain individual single-line strings ending with
// newlines. Such sequences can be obtained from the `readlines()` method
// of file-like objects. The delta generated also consists of newline-
// terminated strings, ready to be printed as-is via the writeline()
// method of a file-like object.
diffs = []string{}
cruncher := NewMatcherWithJunk(a, b, true, d.Linejunk)
opcodes := cruncher.GetOpCodes()
for _, current := range opcodes {
alo := current.I1
ahi := current.I2
blo := current.J1
bhi := current.J2
var g []string
if current.Tag == 'r' {
g, _ = d.FancyReplace(a, alo, ahi, b, blo, bhi)
} else if current.Tag == 'd' {
g = d.Dump("-", a, alo, ahi)
} else if current.Tag == 'i' {
g = d.Dump("+", b, blo, bhi)
} else if current.Tag == 'e' {
g = d.Dump(" ", a, alo, ahi)
} else {
return nil, errors.New(fmt.Sprintf("unknown tag %q", current.Tag))
}
diffs = append(diffs, g...)
}
return diffs, nil
}
func (d *Differ) StructuredDump(tag byte, x []string, low int, high int) (out []DiffLine) {
size := high - low
out = make([]DiffLine, size)
for i := 0; i < size; i++ {
out[i] = NewDiffLine(tag, x[i + low])
}
return out
}
func (d *Differ) Dump(tag string, x []string, low int, high int) (out []string) {
// Generate comparison results for a same-tagged range.
sout := d.StructuredDump(tag[0], x, low, high)
out = make([]string, len(sout))
var bld strings.Builder
bld.Grow(1024)
for i, line := range sout {
bld.Reset()
bld.WriteByte(line.Tag)
bld.WriteString(" ")
bld.WriteString(line.Line)
out[i] = bld.String()
}
return out
}
func (d *Differ) PlainReplace(a []string, alo int, ahi int, b []string, blo int, bhi int) (out []string, err error) {
if !(alo < ahi) || !(blo < bhi) { // assertion
return nil, errors.New("low greater than or equal to high")
}
// dump the shorter block first -- reduces the burden on short-term
// memory if the blocks are of very different sizes
if bhi-blo < ahi-alo {
out = d.Dump("+", b, blo, bhi)
out = append(out, d.Dump("-", a, alo, ahi)...)
} else {
out = d.Dump("-", a, alo, ahi)
out = append(out, d.Dump("+", b, blo, bhi)...)
}
return out, nil
}
func (d *Differ) FancyReplace(a []string, alo int, ahi int, b []string, blo int, bhi int) (out []string, err error) {
// When replacing one block of lines with another, search the blocks
// for *similar* lines; the best-matching pair (if any) is used as a
// synch point, and intraline difference marking is done on the
// similar pair. Lots of work, but often worth it.
// don't synch up unless the lines have a similarity score of at
// least cutoff; best_ratio tracks the best score seen so far
best_ratio := 0.74
cutoff := 0.75
cruncher := NewMatcherWithJunk(a, b, true, d.Charjunk)
eqi := -1 // 1st indices of equal lines (if any)
eqj := -1
out = []string{}
// search for the pair that matches best without being identical
// (identical lines must be junk lines, & we don't want to synch up
// on junk -- unless we have to)
var best_i, best_j int
for j := blo; j < bhi; j++ {
bj := b[j]
cruncher.SetSeq2(listifyString(bj))
for i := alo; i < ahi; i++ {
ai := a[i]
if ai == bj {
if eqi == -1 {
eqi = i
eqj = j
}
continue
}
cruncher.SetSeq1(listifyString(ai))
// computing similarity is expensive, so use the quick
// upper bounds first -- have seen this speed up messy
// compares by a factor of 3.
// note that ratio() is only expensive to compute the first
// time it's called on a sequence pair; the expensive part
// of the computation is cached by cruncher
if cruncher.RealQuickRatio() > best_ratio &&
cruncher.QuickRatio() > best_ratio &&
cruncher.Ratio() > best_ratio {
best_ratio = cruncher.Ratio()
best_i = i
best_j = j
}
}
}
if best_ratio < cutoff {
// no non-identical "pretty close" pair
if eqi == -1 {
// no identical pair either -- treat it as a straight replace
out, _ = d.PlainReplace(a, alo, ahi, b, blo, bhi)
return out, nil
}
// no close pair, but an identical pair -- synch up on that
best_i = eqi
best_j = eqj
best_ratio = 1.0
} else {
// there's a close pair, so forget the identical pair (if any)
eqi = -1
}
// a[best_i] very similar to b[best_j]; eqi is None iff they're not
// identical
// pump out diffs from before the synch point
out = append(out, d.fancyHelper(a, alo, best_i, b, blo, best_j)...)
// do intraline marking on the synch pair
aelt, belt := a[best_i], b[best_j]
if eqi == -1 {
// pump out a '-', '?', '+', '?' quad for the synched lines
var atags, btags string
cruncher.SetSeqs(listifyString(aelt), listifyString(belt))
opcodes := cruncher.GetOpCodes()
for _, current := range opcodes {
ai1 := current.I1
ai2 := current.I2
bj1 := current.J1
bj2 := current.J2
la, lb := ai2-ai1, bj2-bj1
if current.Tag == 'r' {
atags += strings.Repeat("^", la)
btags += strings.Repeat("^", lb)
} else if current.Tag == 'd' {
atags += strings.Repeat("-", la)
} else if current.Tag == 'i' {
btags += strings.Repeat("+", lb)
} else if current.Tag == 'e' {
atags += strings.Repeat(" ", la)
btags += strings.Repeat(" ", lb)
} else {
return nil, errors.New(fmt.Sprintf("unknown tag %q",
current.Tag))
}
}
out = append(out, d.QFormat(aelt, belt, atags, btags)...)
} else {
// the synch pair is identical
out = append(out, " "+aelt)
}
// pump out diffs from after the synch point
out = append(out, d.fancyHelper(a, best_i+1, ahi, b, best_j+1, bhi)...)
return out, nil
}
func (d *Differ) fancyHelper(a []string, alo int, ahi int, b []string, blo int, bhi int) (out []string) {
if alo < ahi {
if blo < bhi {
out, _ = d.FancyReplace(a, alo, ahi, b, blo, bhi)
} else {
out = d.Dump("-", a, alo, ahi)
}
} else if blo < bhi {
out = d.Dump("+", b, blo, bhi)
} else {
out = []string{}
}
return out
}
func (d *Differ) QFormat(aline string, bline string, atags string, btags string) (out []string) {
// Format "?" output and deal with leading tabs.
// Can hurt, but will probably help most of the time.
common := min(count_leading(aline, '\t'), count_leading(bline, '\t'))
common = min(common, count_leading(atags[:common], ' '))
common = min(common, count_leading(btags[:common], ' '))
atags = strings.TrimRightFunc(atags[common:], unicode.IsSpace)
btags = strings.TrimRightFunc(btags[common:], unicode.IsSpace)
out = []string{"- " + aline}
if len(atags) > 0 {
out = append(out, fmt.Sprintf("? %s%s\n",
strings.Repeat("\t", common), atags))
}
out = append(out, "+ "+bline)
if len(btags) > 0 {
out = append(out, fmt.Sprintf("? %s%s\n",
strings.Repeat("\t", common), btags))
}
return out
}
// Convert range to the "ed" format
func formatRangeUnified(start, stop int) string {
// Per the diff spec at http://www.unix.org/single_unix_specification/
beginning := start + 1 // lines start numbering with one
length := stop - start
if length == 1 {
return fmt.Sprintf("%d", beginning)
}
if length == 0 {
beginning -= 1 // empty ranges begin at line just before the range
}
return fmt.Sprintf("%d,%d", beginning, length)
}
// Unified diff parameters
type LineDiffParams struct {
A []string // First sequence lines
FromFile string // First file name
FromDate string // First file time
B []string // Second sequence lines
ToFile string // Second file name
ToDate string // Second file time
Eol string // Headers end of line, defaults to LF
Context int // Number of context lines
AutoJunk bool // If true, use autojunking
IsJunkLine func(string)bool // How to spot junk lines
}
// Compare two sequences of lines; generate the delta as a unified diff.
//
// Unified diffs are a compact way of showing line changes and a few
// lines of context. The number of context lines is set by 'n' which
// defaults to three.
//
// By default, the diff control lines (those with ---, +++, or @@) are
// created with a trailing newline. This is helpful so that inputs
// created from file.readlines() result in diffs that are suitable for
// file.writelines() since both the inputs and outputs have trailing
// newlines.
//
// For inputs that do not have trailing newlines, set the lineterm
// argument to "" so that the output will be uniformly newline free.
//
// The unidiff format normally has a header for filenames and modification
// times. Any or all of these may be specified using strings for
// 'fromfile', 'tofile', 'fromfiledate', and 'tofiledate'.
// The modification times are normally expressed in the ISO 8601 format.
func WriteUnifiedDiff(writer io.Writer, diff LineDiffParams) error {
//buf := bufio.NewWriter(writer)
//defer buf.Flush()
var bld strings.Builder
bld.Reset()
wf := func(format string, args ...interface{}) error {
_, err := fmt.Fprintf(&bld, format, args...)
return err
}
ws := func(s string) error {
_, err := bld.WriteString(s)
return err
}
if len(diff.Eol) == 0 {
diff.Eol = "\n"
}
started := false
m := NewMatcher(diff.A, diff.B)
if diff.AutoJunk || diff.IsJunkLine != nil {
m = NewMatcherWithJunk(diff.A, diff.B, diff.AutoJunk, diff.IsJunkLine)
}
for _, g := range m.GetGroupedOpCodes(diff.Context) {
if !started {
started = true
fromDate := ""
if len(diff.FromDate) > 0 {
fromDate = "\t" + diff.FromDate
}
toDate := ""
if len(diff.ToDate) > 0 {
toDate = "\t" + diff.ToDate
}
if diff.FromFile != "" || diff.ToFile != "" {
err := wf("--- %s%s%s", diff.FromFile, fromDate, diff.Eol)
if err != nil {
return err
}
err = wf("+++ %s%s%s", diff.ToFile, toDate, diff.Eol)
if err != nil {
return err
}
}
}
first, last := g[0], g[len(g)-1]
range1 := formatRangeUnified(first.I1, last.I2)
range2 := formatRangeUnified(first.J1, last.J2)
if err := wf("@@ -%s +%s @@%s", range1, range2, diff.Eol); err != nil {
return err
}
for _, c := range g {
i1, i2, j1, j2 := c.I1, c.I2, c.J1, c.J2
if c.Tag == 'e' {
for _, line := range diff.A[i1:i2] {
if err := ws(" " + line); err != nil {
return err
}
}
continue
}
if c.Tag == 'r' || c.Tag == 'd' {
for _, line := range diff.A[i1:i2] {
if err := ws("-" + line); err != nil {
return err
}
}
}
if c.Tag == 'r' || c.Tag == 'i' {
for _, line := range diff.B[j1:j2] {
if err := ws("+" + line); err != nil {
return err
}
}
}
}
}
buf := bufio.NewWriter(writer)
buf.WriteString(bld.String())
buf.Flush()
return nil
}
// Like WriteUnifiedDiff but returns the diff a string.
func GetUnifiedDiffString(diff LineDiffParams) (string, error) {
w := &bytes.Buffer{}
err := WriteUnifiedDiff(w, diff)
return string(w.Bytes()), err
}
// Convert range to the "ed" format.
func formatRangeContext(start, stop int) string {
// Per the diff spec at http://www.unix.org/single_unix_specification/
beginning := start + 1 // lines start numbering with one
length := stop - start
if length == 0 {
beginning -= 1 // empty ranges begin at line just before the range
}
if length <= 1 {
return fmt.Sprintf("%d", beginning)
}
return fmt.Sprintf("%d,%d", beginning, beginning+length-1)
}
// For backward compatibility. Ugh.
type ContextDiff = LineDiffParams
type UnifiedDiff = LineDiffParams
// Compare two sequences of lines; generate the delta as a context diff.
//
// Context diffs are a compact way of showing line changes and a few
// lines of context. The number of context lines is set by diff.Context
// which defaults to three.
//
// By default, the diff control lines (those with *** or ---) are
// created with a trailing newline.
//
// For inputs that do not have trailing newlines, set the diff.Eol
// argument to "" so that the output will be uniformly newline free.
//
// The context diff format normally has a header for filenames and
// modification times. Any or all of these may be specified using
// strings for diff.FromFile, diff.ToFile, diff.FromDate, diff.ToDate.
// The modification times are normally expressed in the ISO 8601 format.
// If not specified, the strings default to blanks.
func WriteContextDiff(writer io.Writer, diff LineDiffParams) error {
buf := bufio.NewWriter(writer)
defer buf.Flush()
var diffErr error
wf := func(format string, args ...interface{}) {
_, err := buf.WriteString(fmt.Sprintf(format, args...))
if diffErr == nil && err != nil {
diffErr = err
}
}
ws := func(s string) {
_, err := buf.WriteString(s)
if diffErr == nil && err != nil {
diffErr = err
}
}
if len(diff.Eol) == 0 {
diff.Eol = "\n"
}
prefix := map[byte]string{
'i': "+ ",
'd': "- ",
'r': "! ",
'e': " ",
}
started := false
m := NewMatcher(diff.A, diff.B)
if diff.AutoJunk || diff.IsJunkLine != nil {
m = NewMatcherWithJunk(diff.A, diff.B, diff.AutoJunk, diff.IsJunkLine)
}
for _, g := range m.GetGroupedOpCodes(diff.Context) {
if !started {
started = true
fromDate := ""
if len(diff.FromDate) > 0 {
fromDate = "\t" + diff.FromDate
}
toDate := ""
if len(diff.ToDate) > 0 {
toDate = "\t" + diff.ToDate
}
if diff.FromFile != "" || diff.ToFile != "" {
wf("*** %s%s%s", diff.FromFile, fromDate, diff.Eol)
wf("--- %s%s%s", diff.ToFile, toDate, diff.Eol)
}
}
first, last := g[0], g[len(g)-1]
ws("***************" + diff.Eol)
range1 := formatRangeContext(first.I1, last.I2)
wf("*** %s ****%s", range1, diff.Eol)
for _, c := range g {
if c.Tag == 'r' || c.Tag == 'd' {
for _, cc := range g {
if cc.Tag == 'i' {
continue
}
for _, line := range diff.A[cc.I1:cc.I2] {
ws(prefix[cc.Tag] + line)
}
}
break
}
}
range2 := formatRangeContext(first.J1, last.J2)
wf("--- %s ----%s", range2, diff.Eol)
for _, c := range g {
if c.Tag == 'r' || c.Tag == 'i' {
for _, cc := range g {
if cc.Tag == 'd' {
continue
}
for _, line := range diff.B[cc.J1:cc.J2] {
ws(prefix[cc.Tag] + line)
}
}
break
}
}
}
return diffErr
}
// Like WriteContextDiff but returns the diff as a string.
func GetContextDiffString(diff LineDiffParams) (string, error) {
w := &bytes.Buffer{}
err := WriteContextDiff(w, diff)
return string(w.Bytes()), err
}
// Split a string on "\n" while preserving them. The output can be used
// as input for LineDiffParams.
func SplitLines(s string) []string {
lines := strings.SplitAfter(s, "\n")
lines[len(lines)-1] += "\n"
return lines
}
go-difflib-1.2.0/difflib/difflib_test.go 0000664 0000000 0000000 00000036131 13660101765 0020111 0 ustar 00root root 0000000 0000000 package difflib
import (
"bytes"
"fmt"
"math"
"reflect"
"runtime"
"strings"
"testing"
"./tester"
)
func assertAlmostEqual(t *testing.T, a, b float64, places int) {
if math.Abs(a-b) > math.Pow10(-places) {
t.Errorf("%.7f != %.7f", a, b)
}
}
func assertEqual(t *testing.T, a, b interface{}) {
if !reflect.DeepEqual(a, b) {
t.Errorf("%v != %v", a, b)
}
}
func splitChars(s string) []string {
chars := make([]string, 0, len(s))
// Assume ASCII inputs
for i := 0; i != len(s); i++ {
chars = append(chars, string(s[i]))
}
return chars
}
func TestlistifyString(t *testing.T) {
lst := listifyString("qwerty")
if reflect.DeepEqual(lst, []string{"q", "w", "e", "r", "t", "y"}) != true {
t.Fatal("listifyString failure:", lst)
}
}
func TestSequenceMatcherRatio(t *testing.T) {
s := NewMatcher(splitChars("abcd"), splitChars("bcde"))
assertEqual(t, s.Ratio(), 0.75)
assertEqual(t, s.QuickRatio(), 0.75)
assertEqual(t, s.RealQuickRatio(), 1.0)
}
func TestGetOptCodes(t *testing.T) {
a := "qabxcd"
b := "abycdf"
s := NewMatcher(splitChars(a), splitChars(b))
w := &bytes.Buffer{}
for _, op := range s.GetOpCodes() {
fmt.Fprintf(w, "%s a[%d:%d], (%s) b[%d:%d] (%s)\n", string(op.Tag),
op.I1, op.I2, a[op.I1:op.I2], op.J1, op.J2, b[op.J1:op.J2])
}
result := string(w.Bytes())
expected := `d a[0:1], (q) b[0:0] ()
e a[1:3], (ab) b[0:2] (ab)
r a[3:4], (x) b[2:3] (y)
e a[4:6], (cd) b[3:5] (cd)
i a[6:6], () b[5:6] (f)
`
if expected != result {
t.Errorf("unexpected op codes: \n%s", result)
}
}
func TestGroupedOpCodes(t *testing.T) {
a := []string{}
for i := 0; i != 39; i++ {
a = append(a, fmt.Sprintf("%02d", i))
}
b := []string{}
b = append(b, a[:8]...)
b = append(b, " i")
b = append(b, a[8:19]...)
b = append(b, " x")
b = append(b, a[20:22]...)
b = append(b, a[27:34]...)
b = append(b, " y")
b = append(b, a[35:]...)
s := NewMatcher(a, b)
w := &bytes.Buffer{}
for _, g := range s.GetGroupedOpCodes(-1) {
fmt.Fprintf(w, "group\n")
for _, op := range g {
fmt.Fprintf(w, " %s, %d, %d, %d, %d\n", string(op.Tag),
op.I1, op.I2, op.J1, op.J2)
}
}
result := string(w.Bytes())
expected := `group
e, 5, 8, 5, 8
i, 8, 8, 8, 9
e, 8, 11, 9, 12
group
e, 16, 19, 17, 20
r, 19, 20, 20, 21
e, 20, 22, 21, 23
d, 22, 27, 23, 23
e, 27, 30, 23, 26
group
e, 31, 34, 27, 30
r, 34, 35, 30, 31
e, 35, 38, 31, 34
`
if expected != result {
t.Errorf("unexpected op codes: \n%s", result)
}
}
func ExampleGetUnifiedDiffCode() {
a := `one
two
three
four
fmt.Printf("%s,%T",a,b)`
b := `zero
one
three
four`
diff := LineDiffParams{
A: SplitLines(a),
B: SplitLines(b),
FromFile: "Original",
FromDate: "2005-01-26 23:30:50",
ToFile: "Current",
ToDate: "2010-04-02 10:20:52",
Context: 3,
}
result, _ := GetUnifiedDiffString(diff)
fmt.Println(strings.Replace(result, "\t", " ", -1))
// Output:
// --- Original 2005-01-26 23:30:50
// +++ Current 2010-04-02 10:20:52
// @@ -1,5 +1,4 @@
// +zero
// one
// -two
// three
// four
// -fmt.Printf("%s,%T",a,b)
}
func ExampleGetContextDiffCode() {
a := `one
two
three
four
fmt.Printf("%s,%T",a,b)`
b := `zero
one
tree
four`
diff := ContextDiff{
A: SplitLines(a),
B: SplitLines(b),
FromFile: "Original",
ToFile: "Current",
Context: 3,
Eol: "\n",
}
result, _ := GetContextDiffString(diff)
fmt.Print(strings.Replace(result, "\t", " ", -1))
// Output:
// *** Original
// --- Current
// ***************
// *** 1,5 ****
// one
// ! two
// ! three
// four
// - fmt.Printf("%s,%T",a,b)
// --- 1,4 ----
// + zero
// one
// ! tree
// four
}
func ExampleGetContextDiffString() {
a := `one
two
three
four`
b := `zero
one
tree
four`
diff := ContextDiff{
A: SplitLines(a),
B: SplitLines(b),
FromFile: "Original",
ToFile: "Current",
Context: 3,
Eol: "\n",
}
result, _ := GetContextDiffString(diff)
fmt.Printf(strings.Replace(result, "\t", " ", -1))
// Output:
// *** Original
// --- Current
// ***************
// *** 1,4 ****
// one
// ! two
// ! three
// four
// --- 1,4 ----
// + zero
// one
// ! tree
// four
}
func rep(s string, count int) string {
return strings.Repeat(s, count)
}
func TestWithAsciiOneInsert(t *testing.T) {
sm := NewMatcher(splitChars(rep("b", 100)),
splitChars("a"+rep("b", 100)))
assertAlmostEqual(t, sm.Ratio(), 0.995, 3)
assertEqual(t, sm.GetOpCodes(),
[]OpCode{{'i', 0, 0, 0, 1}, {'e', 0, 100, 1, 101}})
assertEqual(t, len(sm.bPopular), 0)
sm = NewMatcher(splitChars(rep("b", 100)),
splitChars(rep("b", 50)+"a"+rep("b", 50)))
assertAlmostEqual(t, sm.Ratio(), 0.995, 3)
assertEqual(t, sm.GetOpCodes(),
[]OpCode{{'e', 0, 50, 0, 50}, {'i', 50, 50, 50, 51}, {'e', 50, 100, 51, 101}})
assertEqual(t, len(sm.bPopular), 0)
}
func TestWithAsciiOnDelete(t *testing.T) {
sm := NewMatcher(splitChars(rep("a", 40)+"c"+rep("b", 40)),
splitChars(rep("a", 40)+rep("b", 40)))
assertAlmostEqual(t, sm.Ratio(), 0.994, 3)
assertEqual(t, sm.GetOpCodes(),
[]OpCode{{'e', 0, 40, 0, 40}, {'d', 40, 41, 40, 40}, {'e', 41, 81, 40, 80}})
}
func TestWithAsciiBJunk(t *testing.T) {
isJunk := func(s string) bool {
return s == " "
}
sm := NewMatcherWithJunk(splitChars(rep("a", 40)+rep("b", 40)),
splitChars(rep("a", 44)+rep("b", 40)), true, isJunk)
assertEqual(t, sm.bJunk, map[string]bool{})
sm = NewMatcherWithJunk(splitChars(rep("a", 40)+rep("b", 40)),
splitChars(rep("a", 44)+rep("b", 40)+rep(" ", 20)), false, isJunk)
assertEqual(t, sm.bJunk, map[string]bool{" ": true})
isJunk = func(s string) bool {
return s == " " || s == "b"
}
sm = NewMatcherWithJunk(splitChars(rep("a", 40)+rep("b", 40)),
splitChars(rep("a", 44)+rep("b", 40)+rep(" ", 20)), false, isJunk)
assertEqual(t, sm.bJunk, map[string]bool{" ": true, "b": true})
}
func TestSFBugsRatioForNullSeqn(t *testing.T) {
sm := NewMatcher(nil, nil)
assertEqual(t, sm.Ratio(), 1.0)
assertEqual(t, sm.QuickRatio(), 1.0)
assertEqual(t, sm.RealQuickRatio(), 1.0)
}
func TestSFBugsComparingEmptyLists(t *testing.T) {
groups := NewMatcher(nil, nil).GetGroupedOpCodes(-1)
assertEqual(t, len(groups), 0)
diff := LineDiffParams{
FromFile: "Original",
ToFile: "Current",
Context: 3,
}
result, err := GetUnifiedDiffString(diff)
assertEqual(t, err, nil)
assertEqual(t, result, "")
}
func TestOutputFormatRangeFormatUnified(t *testing.T) {
// Per the diff spec at http://www.unix.org/single_unix_specification/
//
// Each field shall be of the form:
// %1d", if the range contains exactly one line,
// and:
// "%1d,%1d", , otherwise.
// If a range is empty, its beginning line number shall be the number of
// the line just before the range, or 0 if the empty range starts the file.
fm := formatRangeUnified
assertEqual(t, fm(3, 3), "3,0")
assertEqual(t, fm(3, 4), "4")
assertEqual(t, fm(3, 5), "4,2")
assertEqual(t, fm(3, 6), "4,3")
assertEqual(t, fm(0, 0), "0,0")
}
func TestOutputFormatRangeFormatContext(t *testing.T) {
// Per the diff spec at http://www.unix.org/single_unix_specification/
//
// The range of lines in file1 shall be written in the following format
// if the range contains two or more lines:
// "*** %d,%d ****\n", ,
// and the following format otherwise:
// "*** %d ****\n",
// The ending line number of an empty range shall be the number of the preceding line,
// or 0 if the range is at the start of the file.
//
// Next, the range of lines in file2 shall be written in the following format
// if the range contains two or more lines:
// "--- %d,%d ----\n", ,
// and the following format otherwise:
// "--- %d ----\n",
fm := formatRangeContext
assertEqual(t, fm(3, 3), "3")
assertEqual(t, fm(3, 4), "4")
assertEqual(t, fm(3, 5), "4,5")
assertEqual(t, fm(3, 6), "4,6")
assertEqual(t, fm(0, 0), "0")
}
func TestOutputFormatTabDelimiter(t *testing.T) {
diff := LineDiffParams{
A: splitChars("one"),
B: splitChars("two"),
FromFile: "Original",
FromDate: "2005-01-26 23:30:50",
ToFile: "Current",
ToDate: "2010-04-12 10:20:52",
Eol: "\n",
}
ud, err := GetUnifiedDiffString(diff)
assertEqual(t, err, nil)
assertEqual(t, SplitLines(ud)[:2], []string{
"--- Original\t2005-01-26 23:30:50\n",
"+++ Current\t2010-04-12 10:20:52\n",
})
cd, err := GetContextDiffString(ContextDiff(diff))
assertEqual(t, err, nil)
assertEqual(t, SplitLines(cd)[:2], []string{
"*** Original\t2005-01-26 23:30:50\n",
"--- Current\t2010-04-12 10:20:52\n",
})
}
func TestOutputFormatNoTrailingTabOnEmptyFiledate(t *testing.T) {
diff := LineDiffParams{
A: splitChars("one"),
B: splitChars("two"),
FromFile: "Original",
ToFile: "Current",
Eol: "\n",
}
ud, err := GetUnifiedDiffString(diff)
assertEqual(t, err, nil)
assertEqual(t, SplitLines(ud)[:2], []string{"--- Original\n", "+++ Current\n"})
cd, err := GetContextDiffString(ContextDiff(diff))
assertEqual(t, err, nil)
assertEqual(t, SplitLines(cd)[:2], []string{"*** Original\n", "--- Current\n"})
}
func TestOmitFilenames(t *testing.T) {
diff := LineDiffParams{
A: SplitLines("o\nn\ne\n"),
B: SplitLines("t\nw\no\n"),
Eol: "\n",
}
ud, err := GetUnifiedDiffString(diff)
assertEqual(t, err, nil)
assertEqual(t, SplitLines(ud), []string{
"@@ -0,0 +1,2 @@\n",
"+t\n",
"+w\n",
"@@ -2,2 +3,0 @@\n",
"-n\n",
"-e\n",
"\n",
})
cd, err := GetContextDiffString(ContextDiff(diff))
assertEqual(t, err, nil)
assertEqual(t, SplitLines(cd), []string{
"***************\n",
"*** 0 ****\n",
"--- 1,2 ----\n",
"+ t\n",
"+ w\n",
"***************\n",
"*** 2,3 ****\n",
"- n\n",
"- e\n",
"--- 3 ----\n",
"\n",
})
}
func TestSplitLines(t *testing.T) {
allTests := []struct {
input string
want []string
}{
{"foo", []string{"foo\n"}},
{"foo\nbar", []string{"foo\n", "bar\n"}},
{"foo\nbar\n", []string{"foo\n", "bar\n", "\n"}},
}
for _, test := range allTests {
assertEqual(t, SplitLines(test.input), test.want)
}
}
func benchmarkSplitLines(b *testing.B, count int) {
str := strings.Repeat("foo\n", count)
b.ResetTimer()
n := 0
for i := 0; i < b.N; i++ {
n += len(SplitLines(str))
}
}
func BenchmarkSplitLines100(b *testing.B) {
benchmarkSplitLines(b, 100)
}
func BenchmarkSplitLines10000(b *testing.B) {
benchmarkSplitLines(b, 10000)
}
func prepareFilesToDiff(count, seed int) (As, Bs [][]string) {
defer runtime.GC()
return tester.PrepareStringsToDiff(count, seed)
}
func BenchmarkDiffer(b *testing.B) {
A, B := prepareFilesToDiff(b.N, 0)
fmt.Printf("\nDiff length:")
b.ResetTimer()
differ := NewDiffer()
for i := range A {
var x []string
for n := 0; n < 5; n++ {
x, _ = differ.Compare(A[i], B[i])
}
fmt.Printf(" %v", len(x))
}
fmt.Printf("\n")
}
func BenchmarkMatcher(b *testing.B) {
A, B := prepareFilesToDiff(b.N, 0)
fmt.Printf("\nOpcodes count:")
b.ResetTimer()
for i := range A {
var x []OpCode
for n := 0; n < 5; n++ {
sm := NewMatcher(A[i], B[i])
x = sm.GetOpCodes()
}
fmt.Printf(" %v", len(x))
}
fmt.Printf("\n")
}
func TestDifferCompare(t *testing.T) {
diff := NewDiffer()
// Test
aLst := []string{"foo\n", "bar\n", "baz\n"}
bLst := []string{"foo\n", "bar1\n", "asdf\n", "baz\n"}
out, err := diff.Compare(aLst, bLst)
if err != nil {
t.Fatal("Differ Compare() error:", err)
}
if reflect.DeepEqual(out, []string{
" foo\n",
"- bar\n",
"+ bar1\n",
"? +\n",
"+ asdf\n",
" baz\n",
}) != true {
t.Fatal("Differ Compare failure:", out)
}
}
func TestDifferStructuredDump(t *testing.T) {
diff := NewDiffer()
out := diff.StructuredDump('+',
[]string{"foo", "bar", "baz", "quux", "qwerty"},
1, 3)
expected := []DiffLine{DiffLine{'+', "bar"}, DiffLine{'+', "baz"}}
if !reflect.DeepEqual(out, expected) {
t.Fatal("Differ StructuredDump failure:", out)
}
}
func TestDifferDump(t *testing.T) {
diff := NewDiffer()
out := diff.Dump("+",
[]string{"foo", "bar", "baz", "quux", "qwerty"},
1, 3)
if reflect.DeepEqual(out, []string{"+ bar", "+ baz"}) != true {
t.Fatal("Differ Dump() failure:", out)
}
}
func TestDifferPlainReplace(t *testing.T) {
diff := NewDiffer()
aLst := []string{"one\n", "two\n", "three\n", "four\n", "five\n"}
bLst := []string{"one\n", "two2\n", "three\n", "extra\n"}
// Test a then b
out, err := diff.PlainReplace(aLst, 1, 2, bLst, 1, 2)
if err != nil {
t.Fatal("Differ PlainReplace() error:", err)
}
if reflect.DeepEqual(out, []string{"- two\n", "+ two2\n"}) != true {
t.Fatal("Differ PlainReplace() failure:", out)
}
// Test b then a
out, err = diff.PlainReplace(aLst, 3, 5, bLst, 3, 4)
if err != nil {
t.Fatal("Differ PlainReplace() error:", err)
}
if reflect.DeepEqual(out,
[]string{"+ extra\n", "- four\n", "- five\n"}) != true {
t.Fatal("Differ PlainReplace() failure:", out)
}
}
func TestDifferFancyReplaceAndHelper(t *testing.T) {
diff := NewDiffer()
// Test identical sync point, both full
aLst := []string{"one\n", "asdf\n", "three\n"}
bLst := []string{"one\n", "two2\n", "three\n"}
out, err := diff.FancyReplace(aLst, 0, 3, bLst, 0, 3)
if err != nil {
t.Fatal("Differ FancyReplace() error:", err)
}
if reflect.DeepEqual(out,
[]string{" one\n", "- asdf\n", "+ two2\n", " three\n"}) != true {
t.Fatal("Differ FancyReplace() failure:", out)
}
// Test close sync point, both full
aLst = []string{"one\n", "two123456\n", "asdf\n", "three\n"}
bLst = []string{"one\n", "two123457\n", "qwerty\n", "three\n"}
out, err = diff.FancyReplace(aLst, 1, 3, bLst, 1, 3)
if err != nil {
t.Fatal("Differ FancyReplace() error:", err)
}
if reflect.DeepEqual(out, []string{
"- two123456\n",
"? ^\n",
"+ two123457\n",
"? ^\n",
"- asdf\n",
"+ qwerty\n",
}) != true {
t.Fatal("Differ FancyReplace() failure:", out)
}
// Test no identical no close
aLst = []string{"one\n", "asdf\n", "three\n"}
bLst = []string{"one\n", "qwerty\n", "three\n"}
out, err = diff.FancyReplace(aLst, 1, 2, bLst, 1, 2)
if err != nil {
t.Fatal("Differ FancyReplace() error:", err)
}
if reflect.DeepEqual(out, []string{
"- asdf\n",
"+ qwerty\n",
}) != true {
t.Fatal("Differ FancyReplace() failure:", out)
}
}
func TestDifferQFormat(t *testing.T) {
diff := NewDiffer()
aStr := "\tfoo2bar\n"
aTag := " ^ ^"
bStr := "\tfoo3baz\n"
bTag := " ^ ^"
out := diff.QFormat(aStr, bStr, aTag, bTag)
if reflect.DeepEqual(out, []string{
"- \tfoo2bar\n",
"? \t ^ ^\n",
"+ \tfoo3baz\n",
"? \t ^ ^\n",
}) != true {
t.Fatal("Differ QFormat() failure:", out)
}
}
func TestGetUnifiedDiffString(t *testing.T) {
A := "one\ntwo\nthree\nfour\nfive\nsix\nseven\neight\nnine\nten\n"
B := "one\ntwo\nthr33\nfour\nfive\nsix\nseven\neight\nnine\nten\n"
// Build diff
diff := LineDiffParams{A: SplitLines(A),
FromFile: "file", FromDate: "then",
B: SplitLines(B),
ToFile: "tile", ToDate: "now", Eol: "", Context: 1}
// Run test
diffStr, err := GetUnifiedDiffString(diff)
if err != nil {
t.Fatal("GetUnifiedDiffString error:", err)
}
exp := "--- file\tthen\n+++ tile\tnow\n@@ -2,3 +2,3 @@\n two\n-three\n+thr33\n four\n"
if diffStr != exp {
t.Fatal("GetUnifiedDiffString failure:", diffStr)
}
}
go-difflib-1.2.0/difflib/tester/ 0000775 0000000 0000000 00000000000 13660101765 0016426 5 ustar 00root root 0000000 0000000 go-difflib-1.2.0/difflib/tester/tester.go 0000664 0000000 0000000 00000003100 13660101765 0020255 0 ustar 00root root 0000000 0000000 package tester
import (
"math/rand"
"time"
)
func prepareStrings(seed int64) (A, B []string) {
if seed == -1 {
seed = time.Now().UnixNano()
}
rand.Seed(seed)
// Generate 4000 random lines
lines := [4000]string{}
for i := range lines {
l := rand.Intn(100)
p := make([]byte, l)
rand.Read(p)
lines[i] = string(p)
}
// Generate two 4000 lines documents by picking some lines at random
A = make([]string, 4000)
B = make([]string, len(A))
for i := range A {
// make the first 50 lines more likely to appear
if rand.Intn(100) < 40 {
A[i] = lines[rand.Intn(50)]
} else {
A[i] = lines[rand.Intn(len(lines))]
}
if rand.Intn(100) < 40 {
B[i] = lines[rand.Intn(50)]
} else {
B[i] = lines[rand.Intn(len(lines))]
}
}
// Do some copies from A to B
maxcopy := rand.Intn(len(A)-1)+1
for copied, tocopy := 0, rand.Intn(2*len(A)/3); copied < tocopy; {
l := rand.Intn(rand.Intn(maxcopy-1)+1)
for a,b,n := rand.Intn(len(A)), rand.Intn(len(B)), 0;
a < len(A) && b < len(B) && n < l; a,b,n = a+1,b+1,n+1 {
B[b] = A[a]
copied++
}
}
// And some from B to A
for copied, tocopy := 0, rand.Intn(2*len(A)/3); copied < tocopy; {
l := rand.Intn(rand.Intn(maxcopy-1)+1)
for a,b,n := rand.Intn(len(A)), rand.Intn(len(B)), 0;
a < len(A) && b < len(B) && n < l; a,b,n = a+1,b+1,n+1 {
A[a] = B[b]
copied++
}
}
return
}
func PrepareStringsToDiff(count, seed int) (As, Bs [][]string) {
As = make([][]string, count)
Bs = make([][]string, count)
for i := range As {
As[i], Bs[i] = prepareStrings(int64(i+seed))
}
return
}