Improve diff highlight (#3390)

- Try to reduce memory allocations
- Add possibility to disable diff highlight (can improve performance for large diffs)
- Tweaking with cost for prettier (cleaner) diffs
- Do not calculate diff when the number of removed lines in a block is not equal to the number of added lines (this usually resulted in ugly diffs)
This commit is contained in:
Andrey Nering 2016-08-07 13:49:47 -03:00 committed by 无闻
parent 08c976f811
commit 2772791fda
4 changed files with 60 additions and 66 deletions

View file

@ -334,11 +334,13 @@ RUN_AT_START = true
SCHEDULE = @every 24h
[git]
; Max number of lines allowed of a single file in diff view.
; Disables highlight of added and removed changes
DISABLE_DIFF_HIGHLIGHT = false
; Max number of lines allowed of a single file in diff view
MAX_GIT_DIFF_LINES = 1000
; Max number of characters of a line allowed in diff view.
; Max number of characters of a line allowed in diff view
MAX_GIT_DIFF_LINE_CHARACTERS = 500
; Max number of files shown in diff view.
; Max number of files shown in diff view
MAX_GIT_DIFF_FILES = 100
; Arguments for command 'git gc', e.g. "--aggressive --auto"
; see more on http://git-scm.com/docs/git-gc/1.7.5

View file

@ -26,6 +26,7 @@ import (
"github.com/gogits/gogs/modules/base"
"github.com/gogits/gogs/modules/log"
"github.com/gogits/gogs/modules/process"
"github.com/gogits/gogs/modules/setting"
"github.com/gogits/gogs/modules/template/highlight"
)
@ -70,17 +71,18 @@ var (
)
func diffToHTML(diffs []diffmatchpatch.Diff, lineType DiffLineType) template.HTML {
var buf bytes.Buffer
buf := bytes.NewBuffer(nil)
for i := range diffs {
if diffs[i].Type == diffmatchpatch.DiffInsert && lineType == DIFF_LINE_ADD {
switch {
case diffs[i].Type == diffmatchpatch.DiffInsert && lineType == DIFF_LINE_ADD:
buf.Write(addedCodePrefix)
buf.WriteString(html.EscapeString(diffs[i].Text))
buf.Write(codeTagSuffix)
} else if diffs[i].Type == diffmatchpatch.DiffDelete && lineType == DIFF_LINE_DEL {
case diffs[i].Type == diffmatchpatch.DiffDelete && lineType == DIFF_LINE_DEL:
buf.Write(removedCodePrefix)
buf.WriteString(html.EscapeString(diffs[i].Text))
buf.Write(codeTagSuffix)
} else if diffs[i].Type == diffmatchpatch.DiffEqual {
case diffs[i].Type == diffmatchpatch.DiffEqual:
buf.WriteString(html.EscapeString(diffs[i].Text))
}
}
@ -90,62 +92,86 @@ func diffToHTML(diffs []diffmatchpatch.Diff, lineType DiffLineType) template.HTM
// get an specific line by type (add or del) and file line number
func (diffSection *DiffSection) GetLine(lineType DiffLineType, idx int) *DiffLine {
difference := 0
var (
difference = 0
addCount = 0
delCount = 0
matchDiffLine *DiffLine
)
LOOP:
for _, diffLine := range diffSection.Lines {
if diffLine.Type == DIFF_LINE_PLAIN {
// get the difference of line numbers between ADD and DEL versions
switch diffLine.Type {
case DIFF_LINE_ADD:
addCount++
case DIFF_LINE_DEL:
delCount++
default:
if matchDiffLine != nil {
break LOOP
}
difference = diffLine.RightIdx - diffLine.LeftIdx
continue
addCount = 0
delCount = 0
}
if lineType == DIFF_LINE_DEL {
switch lineType {
case DIFF_LINE_DEL:
if diffLine.RightIdx == 0 && diffLine.LeftIdx == idx-difference {
return diffLine
matchDiffLine = diffLine
}
} else if lineType == DIFF_LINE_ADD {
case DIFF_LINE_ADD:
if diffLine.LeftIdx == 0 && diffLine.RightIdx == idx+difference {
return diffLine
matchDiffLine = diffLine
}
}
}
if addCount == delCount {
return matchDiffLine
}
return nil
}
var diffMatchPatch = diffmatchpatch.New()
func init() {
diffMatchPatch.DiffEditCost = 100
}
// computes inline diff for the given line
func (diffSection *DiffSection) GetComputedInlineDiffFor(diffLine *DiffLine) template.HTML {
var compareDiffLine *DiffLine
var diff1, diff2 string
getDefaultReturn := func() template.HTML {
if setting.Git.DisableDiffHighlight {
return template.HTML(html.EscapeString(diffLine.Content[1:]))
}
// just compute diff for adds and removes
if diffLine.Type != DIFF_LINE_ADD && diffLine.Type != DIFF_LINE_DEL {
return getDefaultReturn()
}
var (
compareDiffLine *DiffLine
diff1 string
diff2 string
)
// try to find equivalent diff line. ignore, otherwise
if diffLine.Type == DIFF_LINE_ADD {
switch diffLine.Type {
case DIFF_LINE_ADD:
compareDiffLine = diffSection.GetLine(DIFF_LINE_DEL, diffLine.RightIdx)
if compareDiffLine == nil {
return getDefaultReturn()
return template.HTML(html.EscapeString(diffLine.Content[1:]))
}
diff1 = compareDiffLine.Content
diff2 = diffLine.Content
} else {
case DIFF_LINE_DEL:
compareDiffLine = diffSection.GetLine(DIFF_LINE_ADD, diffLine.LeftIdx)
if compareDiffLine == nil {
return getDefaultReturn()
return template.HTML(html.EscapeString(diffLine.Content[1:]))
}
diff1 = diffLine.Content
diff2 = compareDiffLine.Content
default:
return template.HTML(html.EscapeString(diffLine.Content[1:]))
}
dmp := diffmatchpatch.New()
diffRecord := dmp.DiffMain(diff1[1:], diff2[1:], true)
diffRecord = dmp.DiffCleanupSemantic(diffRecord)
diffRecord := diffMatchPatch.DiffMain(diff1[1:], diff2[1:], true)
diffRecord = diffMatchPatch.DiffCleanupEfficiency(diffRecord)
return diffToHTML(diffRecord, diffLine.Type)
}

View file

@ -33,38 +33,3 @@ func TestDiffToHTML(t *testing.T) {
dmp.Diff{dmp.DiffEqual, " biz"},
}, DIFF_LINE_DEL))
}
// test if GetLine is return the correct lines
func TestGetLine(t *testing.T) {
ds := DiffSection{Lines: []*DiffLine{
&DiffLine{LeftIdx: 28, RightIdx: 28, Type: DIFF_LINE_PLAIN},
&DiffLine{LeftIdx: 29, RightIdx: 29, Type: DIFF_LINE_PLAIN},
&DiffLine{LeftIdx: 30, RightIdx: 30, Type: DIFF_LINE_PLAIN},
&DiffLine{LeftIdx: 31, RightIdx: 0, Type: DIFF_LINE_DEL},
&DiffLine{LeftIdx: 0, RightIdx: 31, Type: DIFF_LINE_ADD},
&DiffLine{LeftIdx: 0, RightIdx: 32, Type: DIFF_LINE_ADD},
&DiffLine{LeftIdx: 32, RightIdx: 33, Type: DIFF_LINE_PLAIN},
&DiffLine{LeftIdx: 33, RightIdx: 0, Type: DIFF_LINE_DEL},
&DiffLine{LeftIdx: 34, RightIdx: 0, Type: DIFF_LINE_DEL},
&DiffLine{LeftIdx: 35, RightIdx: 0, Type: DIFF_LINE_DEL},
&DiffLine{LeftIdx: 36, RightIdx: 0, Type: DIFF_LINE_DEL},
&DiffLine{LeftIdx: 0, RightIdx: 34, Type: DIFF_LINE_ADD},
&DiffLine{LeftIdx: 0, RightIdx: 35, Type: DIFF_LINE_ADD},
&DiffLine{LeftIdx: 0, RightIdx: 36, Type: DIFF_LINE_ADD},
&DiffLine{LeftIdx: 0, RightIdx: 37, Type: DIFF_LINE_ADD},
&DiffLine{LeftIdx: 37, RightIdx: 38, Type: DIFF_LINE_PLAIN},
&DiffLine{LeftIdx: 38, RightIdx: 39, Type: DIFF_LINE_PLAIN},
}}
assertLineEqual(t, ds.GetLine(DIFF_LINE_ADD, 31), ds.Lines[4])
assertLineEqual(t, ds.GetLine(DIFF_LINE_DEL, 31), ds.Lines[3])
assertLineEqual(t, ds.GetLine(DIFF_LINE_ADD, 33), ds.Lines[11])
assertLineEqual(t, ds.GetLine(DIFF_LINE_ADD, 34), ds.Lines[12])
assertLineEqual(t, ds.GetLine(DIFF_LINE_ADD, 35), ds.Lines[13])
assertLineEqual(t, ds.GetLine(DIFF_LINE_ADD, 36), ds.Lines[14])
assertLineEqual(t, ds.GetLine(DIFF_LINE_DEL, 34), ds.Lines[7])
assertLineEqual(t, ds.GetLine(DIFF_LINE_DEL, 35), ds.Lines[8])
assertLineEqual(t, ds.GetLine(DIFF_LINE_DEL, 36), ds.Lines[9])
assertLineEqual(t, ds.GetLine(DIFF_LINE_DEL, 37), ds.Lines[10])
}

View file

@ -191,6 +191,7 @@ var (
// Git settings
Git struct {
DisableDiffHighlight bool
MaxGitDiffLines int
MaxGitDiffLineCharacters int
MaxGitDiffFiles int