add vendoring

vendor/maunium.net/go/mautrix/format/mdext/nohtml.go

@@ -0,0 +1,61 @@
+// Copyright (c) 2022 Tulir Asokan
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+package mdext
+
+import (
+	"github.com/yuin/goldmark"
+	"github.com/yuin/goldmark/ast"
+	"github.com/yuin/goldmark/renderer"
+	"github.com/yuin/goldmark/renderer/html"
+	"github.com/yuin/goldmark/util"
+)
+
+type extEscapeHTML struct{}
+type escapingHTMLRenderer struct{}
+
+// EscapeHTML is an extension that escapes HTML in the input markdown instead of passing it through as-is.
+var EscapeHTML = &extEscapeHTML{}
+var defaultEHR = &escapingHTMLRenderer{}
+
+func (eeh *extEscapeHTML) Extend(m goldmark.Markdown) {
+	m.Renderer().AddOptions(renderer.WithNodeRenderers(util.Prioritized(defaultEHR, 0)))
+}
+
+func (ehr *escapingHTMLRenderer) RegisterFuncs(reg renderer.NodeRendererFuncRegisterer) {
+	reg.Register(ast.KindHTMLBlock, ehr.renderHTMLBlock)
+	reg.Register(ast.KindRawHTML, ehr.renderRawHTML)
+}
+
+func (ehr *escapingHTMLRenderer) renderRawHTML(w util.BufWriter, source []byte, node ast.Node, entering bool) (ast.WalkStatus, error) {
+	if !entering {
+		return ast.WalkSkipChildren, nil
+	}
+	n := node.(*ast.RawHTML)
+	l := n.Segments.Len()
+	for i := 0; i < l; i++ {
+		segment := n.Segments.At(i)
+		html.DefaultWriter.RawWrite(w, segment.Value(source))
+	}
+	return ast.WalkSkipChildren, nil
+}
+
+func (ehr *escapingHTMLRenderer) renderHTMLBlock(w util.BufWriter, source []byte, node ast.Node, entering bool) (ast.WalkStatus, error) {
+	n := node.(*ast.HTMLBlock)
+	if entering {
+		l := n.Lines().Len()
+		for i := 0; i < l; i++ {
+			line := n.Lines().At(i)
+			html.DefaultWriter.RawWrite(w, line.Value(source))
+		}
+	} else {
+		if n.HasClosure() {
+			closure := n.ClosureLine
+			html.DefaultWriter.RawWrite(w, closure.Value(source))
+		}
+	}
+	return ast.WalkContinue, nil
+}