Fixed emoji alias not parsed in links (go-gitea#16221)

* Do not skip links.

* Restrict text in links to emojis.

Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>
Co-authored-by: zeripath <art27@cantab.net>

modules/markup/html.go

@@ -322,7 +322,7 @@ func postProcess(ctx *RenderContext, procs []processor, input io.Reader, output
  node = node.FirstChild
  }
 
- visitNode(ctx, procs, node, true)
+ visitNode(ctx, procs, procs, node)
 
  newNodes := make([]*html.Node, 0, 5)
 
@@ -354,24 +354,22 @@ func postProcess(ctx *RenderContext, procs []processor, input io.Reader, output
  return nil
 }
 
-func visitNode(ctx *RenderContext, procs []processor, node *html.Node, visitText bool) {
+func visitNode(ctx *RenderContext, procs, textProcs []processor, node *html.Node) {
  // Add user-content- to IDs if they don't already have them
  for idx, attr := range node.Attr {
  if attr.Key == "id" && !(strings.HasPrefix(attr.Val, "user-content-") || blackfridayExtRegex.MatchString(attr.Val)) {
  node.Attr[idx].Val = "user-content-" + attr.Val
  }
 
  if attr.Key == "class" && attr.Val == "emoji" {
- visitText = false
+ textProcs = nil
  }
  }
 
- // We ignore code, pre and already generated links.
+ // We ignore code and pre.
  switch node.Type {
  case html.TextNode:
- if visitText {
- textNode(ctx, procs, node)
- }
+ textNode(ctx, textProcs, node)
  case html.ElementNode:
  if node.Data == "img" {
  for i, attr := range node.Attr {
@@ -390,7 +388,8 @@ func visitNode(ctx *RenderContext, procs []processor, node *html.Node, visitText
  node.Attr[i] = attr
  }
  } else if node.Data == "a" {
- visitText = false
+ // Restrict text in links to emojis
+ textProcs = emojiProcessors
  } else if node.Data == "code" || node.Data == "pre" {
  return
  } else if node.Data == "i" {
@@ -416,7 +415,7 @@ func visitNode(ctx *RenderContext, procs []processor, node *html.Node, visitText
  }
  }
  for n := node.FirstChild; n != nil; n = n.NextSibling {
- visitNode(ctx, procs, n, visitText)
+ visitNode(ctx, procs, textProcs, n)
  }
  }
  // ignore everything else

modules/markup/markdown/markdown_test.go

@@ -391,5 +391,13 @@ func TestRenderSiblingImages_Issue12925(t *testing.T) {
  res, err := RenderRawString(&markup.RenderContext{}, testcase)
  assert.NoError(t, err)
  assert.Equal(t, expected, res)
+}
 
+func TestRenderEmojiInLinks_Issue12331(t *testing.T) {
+ testcase := `[Link with emoji :moon: in text](https://gitea.io)`
+ expected := `<p><a href="https://gitea.io" rel="nofollow">Link with emoji <span class="emoji" aria-label="waxing gibbous moon">🌔</span> in text</a></p>
+`
+ res, err := RenderString(&markup.RenderContext{}, testcase)
+ assert.NoError(t, err)
+ assert.Equal(t, expected, res)
 }