Refactor markup render system (#32533)

Remove unmaintainable sanitizer rules. No need to add special "class"
regexp rules anymore, use RenderInternal.SafeAttr instead, more details
(and examples) are in the tests

modules/markup/markdown/math/block_renderer.go

@@ -4,17 +4,21 @@
 package math
 
 import (
+	"code.gitea.io/gitea/modules/markup/internal"
+
 	gast "github.com/yuin/goldmark/ast"
 	"github.com/yuin/goldmark/renderer"
 	"github.com/yuin/goldmark/util"
 )
 
 // BlockRenderer represents a renderer for math Blocks
-type BlockRenderer struct{}
+type BlockRenderer struct {
+	renderInternal *internal.RenderInternal
+}
 
 // NewBlockRenderer creates a new renderer for math Blocks
-func NewBlockRenderer() renderer.NodeRenderer {
-	return &BlockRenderer{}
+func NewBlockRenderer(renderInternal *internal.RenderInternal) renderer.NodeRenderer {
+	return &BlockRenderer{renderInternal: renderInternal}
 }
 
 // RegisterFuncs registers the renderer for math Blocks
@@ -33,7 +37,7 @@ func (r *BlockRenderer) writeLines(w util.BufWriter, source []byte, n gast.Node)
 func (r *BlockRenderer) renderBlock(w util.BufWriter, source []byte, node gast.Node, entering bool) (gast.WalkStatus, error) {
 	n := node.(*Block)
 	if entering {
-		_, _ = w.WriteString(`<pre class="code-block is-loading"><code class="chroma language-math display">`)
+		_ = r.renderInternal.FormatWithSafeAttrs(w, `<pre class="code-block is-loading"><code class="chroma language-math display">`)
 		r.writeLines(w, source, n)
 	} else {
 		_, _ = w.WriteString(`</code></pre>` + "\n")

modules/markup/markdown/math/inline_renderer.go

@@ -6,17 +6,21 @@ package math
 import (
 	"bytes"
 
+	"code.gitea.io/gitea/modules/markup/internal"
+
 	"github.com/yuin/goldmark/ast"
 	"github.com/yuin/goldmark/renderer"
 	"github.com/yuin/goldmark/util"
 )
 
 // InlineRenderer is an inline renderer
-type InlineRenderer struct{}
+type InlineRenderer struct {
+	renderInternal *internal.RenderInternal
+}
 
 // NewInlineRenderer returns a new renderer for inline math
-func NewInlineRenderer() renderer.NodeRenderer {
-	return &InlineRenderer{}
+func NewInlineRenderer(renderInternal *internal.RenderInternal) renderer.NodeRenderer {
+	return &InlineRenderer{renderInternal: renderInternal}
 }
 
 func (r *InlineRenderer) renderInline(w util.BufWriter, source []byte, n ast.Node, entering bool) (ast.WalkStatus, error) {
@@ -25,7 +29,7 @@ func (r *InlineRenderer) renderInline(w util.BufWriter, source []byte, n ast.Nod
 		if _, ok := n.(*InlineBlock); ok {
 			extraClass = "display "
 		}
-		_, _ = w.WriteString(`<code class="language-math ` + extraClass + `is-loading">`)
+		_ = r.renderInternal.FormatWithSafeAttrs(w, `<code class="language-math %sis-loading">`, extraClass)
 		for c := n.FirstChild(); c != nil; c = c.NextSibling() {
 			segment := c.(*ast.Text).Segment
 			value := util.EscapeHTML(segment.Value(source))

modules/markup/markdown/math/math.go

@@ -4,6 +4,8 @@
 package math
 
 import (
+	"code.gitea.io/gitea/modules/markup/internal"
+
 	"github.com/yuin/goldmark"
 	"github.com/yuin/goldmark/parser"
 	"github.com/yuin/goldmark/renderer"
@@ -12,6 +14,7 @@ import (
 
 // Extension is a math extension
 type Extension struct {
+	renderInternal    *internal.RenderInternal
 	enabled           bool
 	parseDollarInline bool
 	parseDollarBlock  bool
@@ -39,38 +42,10 @@ func Enabled(enable ...bool) Option {
 	})
 }
 
-// WithInlineDollarParser enables or disables the parsing of $...$
-func WithInlineDollarParser(enable ...bool) Option {
-	value := true
-	if len(enable) > 0 {
-		value = enable[0]
-	}
-	return extensionFunc(func(e *Extension) {
-		e.parseDollarInline = value
-	})
-}
-
-// WithBlockDollarParser enables or disables the parsing of $$...$$
-func WithBlockDollarParser(enable ...bool) Option {
-	value := true
-	if len(enable) > 0 {
-		value = enable[0]
-	}
-	return extensionFunc(func(e *Extension) {
-		e.parseDollarBlock = value
-	})
-}
-
-// Math represents a math extension with default rendered delimiters
-var Math = &Extension{
-	enabled:           true,
-	parseDollarBlock:  true,
-	parseDollarInline: true,
-}
-
 // NewExtension creates a new math extension with the provided options
-func NewExtension(opts ...Option) *Extension {
+func NewExtension(renderInternal *internal.RenderInternal, opts ...Option) *Extension {
 	r := &Extension{
+		renderInternal:    renderInternal,
 		enabled:           true,
 		parseDollarBlock:  true,
 		parseDollarInline: true,
@@ -102,7 +77,7 @@ func (e *Extension) Extend(m goldmark.Markdown) {
 	m.Parser().AddOptions(parser.WithInlineParsers(inlines...))
 
 	m.Renderer().AddOptions(renderer.WithNodeRenderers(
-		util.Prioritized(NewBlockRenderer(), 501),
-		util.Prioritized(NewInlineRenderer(), 502),
+		util.Prioritized(NewBlockRenderer(e.renderInternal), 501),
+		util.Prioritized(NewInlineRenderer(e.renderInternal), 502),
 	))
 }