From 88c2e2436001c868c2583950b5f9eb0516424b7d Mon Sep 17 00:00:00 2001 From: zeripath Date: Tue, 13 Sep 2022 17:33:37 +0100 Subject: Add KaTeX rendering to Markdown. (#20571) This PR adds mathematical rendering with KaTeX. The first step is to add a Goldmark extension that detects the latex (and tex) mathematics delimiters. The second step to make this extension only run if math support is enabled. The second step is to then add KaTeX CSS and JS to the head which will load after the dom is rendered. Fix #3445 Signed-off-by: Andrew Thornton Signed-off-by: Andrew Thornton Co-authored-by: silverwind Co-authored-by: Lunny Xiao --- modules/markup/markdown/math/inline_renderer.go | 47 +++++++++++++++++++++++++ 1 file changed, 47 insertions(+) create mode 100644 modules/markup/markdown/math/inline_renderer.go (limited to 'modules/markup/markdown/math/inline_renderer.go') diff --git a/modules/markup/markdown/math/inline_renderer.go b/modules/markup/markdown/math/inline_renderer.go new file mode 100644 index 0000000000..e4c0f3761d --- /dev/null +++ b/modules/markup/markdown/math/inline_renderer.go @@ -0,0 +1,47 @@ +// Copyright 2022 The Gitea Authors. All rights reserved. +// Use of this source code is governed by a MIT-style +// license that can be found in the LICENSE file. + +package math + +import ( + "bytes" + + "github.com/yuin/goldmark/ast" + "github.com/yuin/goldmark/renderer" + "github.com/yuin/goldmark/util" +) + +// InlineRenderer is an inline renderer +type InlineRenderer struct{} + +// NewInlineRenderer returns a new renderer for inline math +func NewInlineRenderer() renderer.NodeRenderer { + return &InlineRenderer{} +} + +func (r *InlineRenderer) renderInline(w util.BufWriter, source []byte, n ast.Node, entering bool) (ast.WalkStatus, error) { + if entering { + _, _ = w.WriteString(``) + for c := n.FirstChild(); c != nil; c = c.NextSibling() { + segment := c.(*ast.Text).Segment + value := util.EscapeHTML(segment.Value(source)) + if bytes.HasSuffix(value, []byte("\n")) { + _, _ = w.Write(value[:len(value)-1]) + if c != n.LastChild() { + _, _ = w.Write([]byte(" ")) + } + } else { + _, _ = w.Write(value) + } + } + return ast.WalkSkipChildren, nil + } + _, _ = w.WriteString(``) + return ast.WalkContinue, nil +} + +// RegisterFuncs registers the renderer for inline math nodes +func (r *InlineRenderer) RegisterFuncs(reg renderer.NodeRendererFuncRegisterer) { + reg.Register(KindInline, r.renderInline) +} -- cgit v1.2.3