Upgrade chroma to v2.3.0 (#21259)

The behaviour of `PreventSurroundingPre` has changed in
https://github.com/alecthomas/chroma/pull/618 so that apparently it now
causes line wrapper tags to be no longer emitted, but we need some form
of indication to split the HTML into lines, so I did what
https://github.com/yuin/goldmark-highlighting/pull/33 did and added the
`nopWrapper`.

Maybe there are more elegant solutions but for some reason, just
splitting the HTML string on `\n` did not work.

Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

4 files changed, 25 insertions, 30 deletions

diff --git a/modules/highlight/highlight.go b/modules/highlight/highlight.go
index af3376e8d7..65ed74b019 100644
--- a/modules/highlight/highlight.go
+++ b/modules/highlight/highlight.go
@@ -19,10 +19,10 @@ import (
 	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/setting"
 
-	"github.com/alecthomas/chroma"
-	"github.com/alecthomas/chroma/formatters/html"
-	"github.com/alecthomas/chroma/lexers"
-	"github.com/alecthomas/chroma/styles"
+	"github.com/alecthomas/chroma/v2"
+	"github.com/alecthomas/chroma/v2/formatters/html"
+	"github.com/alecthomas/chroma/v2/lexers"
+	"github.com/alecthomas/chroma/v2/styles"
 	lru "github.com/hashicorp/golang-lru"
 )
 
@@ -147,9 +147,6 @@ func File(fileName, language string, code []byte) ([]string, error) {
 		html.PreventSurroundingPre(true),
 	)
 
-	htmlBuf := bytes.Buffer{}
-	htmlWriter := bufio.NewWriter(&htmlBuf)
-
 	var lexer chroma.Lexer
 
 	// provided language overrides everything
@@ -180,23 +177,21 @@ func File(fileName, language string, code []byte) ([]string, error) {
 		return nil, fmt.Errorf("can't tokenize code: %w", err)
 	}
 
-	err = formatter.Format(htmlWriter, styles.GitHub, iterator)
-	if err != nil {
-		return nil, fmt.Errorf("can't format code: %w", err)
-	}
-
-	_ = htmlWriter.Flush()
+	tokensLines := chroma.SplitTokensIntoLines(iterator.Tokens())
+	htmlBuf := &bytes.Buffer{}
 
-	// at the moment, Chroma generates stable output `<span class="line"><span class="cl">...\n</span></span>` for each line
-	htmlStr := htmlBuf.String()
-	lines := strings.Split(htmlStr, `<span class="line"><span class="cl">`)
-	m := make([]string, 0, len(lines))
-	for i := 1; i < len(lines); i++ {
-		line := lines[i]
-		line = strings.TrimSuffix(line, "</span></span>")
-		m = append(m, line)
+	lines := make([]string, 0, len(tokensLines))
+	for _, tokens := range tokensLines {
+		iterator = chroma.Literator(tokens...)
+		err = formatter.Format(htmlBuf, styles.GitHub, iterator)
+		if err != nil {
+			return nil, fmt.Errorf("can't format code: %w", err)
+		}
+		lines = append(lines, htmlBuf.String())
+		htmlBuf.Reset()
 	}
-	return m, nil
+
+	return lines, nil
 }
 
 // PlainText returns non-highlighted HTML for code
diff --git a/modules/markup/markdown/markdown.go b/modules/markup/markdown/markdown.go
index c0e72fd6ce..fa289986cc 100644
--- a/modules/markup/markdown/markdown.go
+++ b/modules/markup/markdown/markdown.go
@@ -18,9 +18,9 @@ import (
 	"code.gitea.io/gitea/modules/setting"
 	giteautil "code.gitea.io/gitea/modules/util"
 
-	chromahtml "github.com/alecthomas/chroma/formatters/html"
+	chromahtml "github.com/alecthomas/chroma/v2/formatters/html"
 	"github.com/yuin/goldmark"
-	highlighting "github.com/yuin/goldmark-highlighting"
+	highlighting "github.com/yuin/goldmark-highlighting/v2"
 	meta "github.com/yuin/goldmark-meta"
 	"github.com/yuin/goldmark/extension"
 	"github.com/yuin/goldmark/parser"
diff --git a/modules/markup/orgmode/orgmode.go b/modules/markup/orgmode/orgmode.go
index a78531720d..1c02f274ba 100644
--- a/modules/markup/orgmode/orgmode.go
+++ b/modules/markup/orgmode/orgmode.go
@@ -17,8 +17,8 @@ import (
 	"code.gitea.io/gitea/modules/setting"
 	"code.gitea.io/gitea/modules/util"
 
-	"github.com/alecthomas/chroma"
-	"github.com/alecthomas/chroma/lexers"
+	"github.com/alecthomas/chroma/v2"
+	"github.com/alecthomas/chroma/v2/lexers"
 	"github.com/niklasfasching/go-org/org"
 )
 
diff --git a/modules/markup/orgmode/orgmode_test.go b/modules/markup/orgmode/orgmode_test.go
index 4fc0a20db2..cd12cd8c17 100644
--- a/modules/markup/orgmode/orgmode_test.go
+++ b/modules/markup/orgmode/orgmode_test.go
@@ -79,9 +79,9 @@ func HelloWorld() {
 }
 #+end_src
 `, `<div class="src src-go">
-<pre><code class="chroma language-go"><span class="line"><span class="cl"><span class="c1">// HelloWorld prints &#34;Hello World&#34;
-</span></span></span><span class="line"><span class="cl"><span class="c1"></span><span class="kd">func</span> <span class="nf">HelloWorld</span><span class="p">()</span> <span class="p">{</span>
-</span></span><span class="line"><span class="cl">	<span class="nx">fmt</span><span class="p">.</span><span class="nf">Println</span><span class="p">(</span><span class="s">&#34;Hello World&#34;</span><span class="p">)</span>
-</span></span><span class="line"><span class="cl"><span class="p">}</span></span></span></code></pre>
+<pre><code class="chroma language-go"><span class="c1">// HelloWorld prints &#34;Hello World&#34;
+</span><span class="c1"></span><span class="kd">func</span> <span class="nf">HelloWorld</span><span class="p">()</span> <span class="p">{</span>
+	<span class="nx">fmt</span><span class="p">.</span><span class="nf">Println</span><span class="p">(</span><span class="s">&#34;Hello World&#34;</span><span class="p">)</span>
+<span class="p">}</span></code></pre>
 </div>`)
 }