Full-file syntax highlighting for diff pages (#33766)

Fix #33358, fix #21970

This adds a step in the `GitDiffForRender` that does syntax highlighting for the
entire file and then only references lines from that syntax highlighted
code. This allows things like multi-line comments to be syntax
highlighted correctly.

---------

Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>
This commit is contained in:
Dustin Firebaugh
2025-03-08 23:51:58 -05:00
committed by GitHub
parent 6f13331754
commit 3f1f808b9e
14 changed files with 361 additions and 323 deletions

View File

@ -5,121 +5,72 @@ package gitdiff
import (
"fmt"
"html/template"
"strings"
"testing"
"github.com/sergi/go-diff/diffmatchpatch"
"github.com/stretchr/testify/assert"
)
func TestDiffWithHighlight(t *testing.T) {
hcd := newHighlightCodeDiff()
diffs := hcd.diffWithHighlight(
"main.v", "",
" run('<>')\n",
" run(db)\n",
)
t.Run("DiffLineAddDel", func(t *testing.T) {
hcd := newHighlightCodeDiff()
codeA := template.HTML(`x <span class="k">foo</span> y`)
codeB := template.HTML(`x <span class="k">bar</span> y`)
outDel := hcd.diffLineWithHighlight(DiffLineDel, codeA, codeB)
assert.Equal(t, `x <span class="k"><span class="removed-code">foo</span></span> y`, string(outDel))
outAdd := hcd.diffLineWithHighlight(DiffLineAdd, codeA, codeB)
assert.Equal(t, `x <span class="k"><span class="added-code">bar</span></span> y`, string(outAdd))
})
expected := ` <span class="n">run</span><span class="o">(</span><span class="removed-code"><span class="k">&#39;</span><span class="o">&lt;</span><span class="o">&gt;</span><span class="k">&#39;</span></span><span class="o">)</span>`
output := diffToHTML(nil, diffs, DiffLineDel)
assert.Equal(t, expected, output)
expected = ` <span class="n">run</span><span class="o">(</span><span class="added-code"><span class="n">db</span></span><span class="o">)</span>`
output = diffToHTML(nil, diffs, DiffLineAdd)
assert.Equal(t, expected, output)
hcd = newHighlightCodeDiff()
hcd.placeholderTokenMap['O'] = "<span>"
hcd.placeholderTokenMap['C'] = "</span>"
diff := diffmatchpatch.Diff{}
diff.Text = "OC"
hcd.recoverOneDiff(&diff)
assert.Equal(t, "<span></span>", diff.Text)
diff.Text = "O"
hcd.recoverOneDiff(&diff)
assert.Equal(t, "<span></span>", diff.Text)
diff.Text = "C"
hcd.recoverOneDiff(&diff)
assert.Equal(t, "", diff.Text)
t.Run("OpenCloseTags", func(t *testing.T) {
hcd := newHighlightCodeDiff()
hcd.placeholderTokenMap['O'], hcd.placeholderTokenMap['C'] = "<span>", "</span>"
assert.Equal(t, "<span></span>", string(hcd.recoverOneDiff("OC")))
assert.Equal(t, "<span></span>", string(hcd.recoverOneDiff("O")))
assert.Equal(t, "", string(hcd.recoverOneDiff("C")))
})
}
func TestDiffWithHighlightPlaceholder(t *testing.T) {
hcd := newHighlightCodeDiff()
diffs := hcd.diffWithHighlight(
"main.js", "",
"a='\U00100000'",
"a='\U0010FFFD''",
)
output := hcd.diffLineWithHighlight(DiffLineDel, "a='\U00100000'", "a='\U0010FFFD''")
assert.Equal(t, "", hcd.placeholderTokenMap[0x00100000])
assert.Equal(t, "", hcd.placeholderTokenMap[0x0010FFFD])
expected := fmt.Sprintf(`<span class="nx">a</span><span class="o">=</span><span class="s1">&#39;</span><span class="removed-code">%s</span>&#39;`, "\U00100000")
output := diffToHTML(hcd.lineWrapperTags, diffs, DiffLineDel)
assert.Equal(t, expected, output)
expected := fmt.Sprintf(`a='<span class="removed-code">%s</span>'`, "\U00100000")
assert.Equal(t, expected, string(output))
hcd = newHighlightCodeDiff()
diffs = hcd.diffWithHighlight(
"main.js", "",
"a='\U00100000'",
"a='\U0010FFFD'",
)
expected = fmt.Sprintf(`<span class="nx">a</span><span class="o">=</span><span class="s1">&#39;</span><span class="added-code">%s</span>&#39;`, "\U0010FFFD")
output = diffToHTML(nil, diffs, DiffLineAdd)
assert.Equal(t, expected, output)
output = hcd.diffLineWithHighlight(DiffLineAdd, "a='\U00100000'", "a='\U0010FFFD'")
expected = fmt.Sprintf(`a='<span class="added-code">%s</span>'`, "\U0010FFFD")
assert.Equal(t, expected, string(output))
}
func TestDiffWithHighlightPlaceholderExhausted(t *testing.T) {
hcd := newHighlightCodeDiff()
hcd.placeholderMaxCount = 0
diffs := hcd.diffWithHighlight(
"main.js", "",
"'",
``,
)
output := diffToHTML(nil, diffs, DiffLineDel)
expected := fmt.Sprintf(`<span class="removed-code">%s#39;</span>`, "\uFFFD")
assert.Equal(t, expected, output)
hcd = newHighlightCodeDiff()
hcd.placeholderMaxCount = 0
diffs = hcd.diffWithHighlight(
"main.js", "",
"a < b",
"a > b",
)
output = diffToHTML(nil, diffs, DiffLineDel)
expected = fmt.Sprintf(`a %s<span class="removed-code">l</span>t; b`, "\uFFFD")
assert.Equal(t, expected, output)
output = diffToHTML(nil, diffs, DiffLineAdd)
expected = fmt.Sprintf(`a %s<span class="added-code">g</span>t; b`, "\uFFFD")
assert.Equal(t, expected, output)
placeHolderAmp := string(rune(0xFFFD))
output := hcd.diffLineWithHighlight(DiffLineDel, `<span class="k">&lt;</span>`, `<span class="k">&gt;</span>`)
assert.Equal(t, placeHolderAmp+"lt;", string(output))
output = hcd.diffLineWithHighlight(DiffLineAdd, `<span class="k">&lt;</span>`, `<span class="k">&gt;</span>`)
assert.Equal(t, placeHolderAmp+"gt;", string(output))
}
func TestDiffWithHighlightTagMatch(t *testing.T) {
totalOverflow := 0
for i := 0; i < 100; i++ {
hcd := newHighlightCodeDiff()
hcd.placeholderMaxCount = i
diffs := hcd.diffWithHighlight(
"main.js", "",
"a='1'",
"b='2'",
)
totalOverflow += hcd.placeholderOverflowCount
output := diffToHTML(nil, diffs, DiffLineDel)
c1 := strings.Count(output, "<span")
c2 := strings.Count(output, "</span")
assert.Equal(t, c1, c2)
output = diffToHTML(nil, diffs, DiffLineAdd)
c1 = strings.Count(output, "<span")
c2 = strings.Count(output, "</span")
assert.Equal(t, c1, c2)
f := func(t *testing.T, lineType DiffLineType) {
totalOverflow := 0
for i := 0; ; i++ {
hcd := newHighlightCodeDiff()
hcd.placeholderMaxCount = i
output := string(hcd.diffLineWithHighlight(lineType, `<span class="k">&lt;</span>`, `<span class="k">&gt;</span>`))
totalOverflow += hcd.placeholderOverflowCount
assert.Equal(t, strings.Count(output, "<span"), strings.Count(output, "</span"))
if hcd.placeholderOverflowCount == 0 {
break
}
}
assert.NotZero(t, totalOverflow)
}
assert.NotZero(t, totalOverflow)
t.Run("DiffLineAdd", func(t *testing.T) { f(t, DiffLineAdd) })
t.Run("DiffLineDel", func(t *testing.T) { f(t, DiffLineDel) })
}