Restrict text in links to emojis.

modules/markup/html.go

@@ -310,7 +310,7 @@ func postProcess(ctx *RenderContext, procs []processor, input io.Reader, output
 	}
 
 	for _, node := range nodes {
-		visitNode(ctx, procs, node, true)
+		visitNode(ctx, procs, procs, node)
 	}
 
 	newNodes := make([]*html.Node, 0, len(nodes))
@@ -346,24 +346,22 @@ 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 _, attr := range node.Attr {
@@ -380,6 +378,9 @@ func visitNode(ctx *RenderContext, procs []processor, node *html.Node, visitText
 					attr.Val = util.URLJoin(prefix, attr.Val)
 				}
 			}
+		} else if node.Data == "a" {
+			// Restrict text in links to emojis
+			textProcs = emojiProcessors
 		} else if node.Data == "code" || node.Data == "pre" {
 			return
 		} else if node.Data == "i" {
@@ -405,7 +406,7 @@ 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

@@ -387,5 +387,13 @@ 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)
 }