enhance(markup): improve issue title rendering (#37908)

modules/markup/html_emoji.go

@@ -69,6 +69,11 @@ func emojiShortCodeProcessor(ctx *RenderContext, node *html.Node) {
 		m[1] += start
 		start = m[1]
 
+		// don't render a shortcode whose ":" directly follows a backtick (an unclosed code span)
+		if m[0] > 0 && node.Data[m[0]-1] == '`' {
+			continue
+		}
+
 		alias := node.Data[m[0]:m[1]]
 
 		var nextChar byte

modules/markup/html_test.go

@@ -377,6 +377,9 @@ func TestRender_emoji(t *testing.T) {
 	test(":100:200", `<p>:100:200</p>`)
 	test("std::thread::something", `<p>std::thread::something</p>`)
 	test(":not exist:", `<p>:not exist:</p>`)
+	test("foo `:smile:", "<p>foo `:smile:</p>")
+	test("foo `:smile:`", `<p>foo <code>:smile:</code></p>`)
+	test("foo ` :smile:", "<p>foo ` <span class=\"emoji\" aria-label=\"grinning face with smiling eyes\">😄</span></p>")
 }
 
 func TestRender_ShortLinks(t *testing.T) {

modules/templates/util_render.go

@@ -107,19 +107,26 @@ func renderCodeBlock(htmlEscapedTextToRender template.HTML) template.HTML {
 
 // RenderIssueTitle renders issue/pull title with defined post processors
 func (ut *RenderUtils) RenderIssueTitle(text string, repo *repo.Repository) template.HTML {
-	renderedText, err := markup.PostProcessIssueTitle(renderhelper.NewRenderContextRepoComment(ut.ctx, repo), template.HTMLEscapeString(text))
+	// wrap "`…`" in <code> before post-processing so code-span content stays literal, like comment bodies
+	htmlWithCode := renderCodeBlock(template.HTML(template.HTMLEscapeString(text)))
+	renderedText, err := markup.PostProcessIssueTitle(renderhelper.NewRenderContextRepoComment(ut.ctx, repo), string(htmlWithCode))
 	if err != nil {
 		log.Error("PostProcessIssueTitle: %v", err)
 		return ""
 	}
-	return renderCodeBlock(template.HTML(renderedText))
+	return template.HTML(renderedText)
 }
 
 // RenderIssueSimpleTitle only renders with emoji and inline code block
 func (ut *RenderUtils) RenderIssueSimpleTitle(text string) template.HTML {
-	ret := ut.RenderEmoji(text)
-	ret = renderCodeBlock(ret)
-	return ret
+	// see RenderIssueTitle: wrap code spans before processing emoji
+	htmlWithCode := renderCodeBlock(template.HTML(template.HTMLEscapeString(text)))
+	renderedText, err := markup.PostProcessEmoji(markup.NewRenderContext(ut.ctx), string(htmlWithCode))
+	if err != nil {
+		log.Error("RenderIssueSimpleTitle: %v", err)
+		return ""
+	}
+	return template.HTML(renderedText)
 }
 
 func (ut *RenderUtils) RenderLabel(label *issues_model.Label) template.HTML {

modules/templates/util_render_test.go

@@ -180,6 +180,38 @@ mail@domain.com
 	})
 }
 
+func TestRenderIssueTitleCodeSpan(t *testing.T) {
+	defer test.MockVariableValue(&markup.RenderBehaviorForTesting.DisableAdditionalAttributes, true)()
+	mockRepo := &repo.Repository{
+		ID: 1, OwnerName: "user13", Name: "repo11",
+		Owner: &user_model.User{ID: 13, Name: "user13"},
+		Units: []*repo.RepoUnit{},
+	}
+	ut := newTestRenderUtils(t)
+
+	cases := []struct {
+		input     string
+		expected  string
+		emojiSafe bool
+	}{
+		{"foo `:100:`", `foo <code class="inline-code-block">:100:</code>`, true},
+		{"`#123`", `<code class="inline-code-block">#123</code>`, false},
+		{"`88fc37a3c0a4dda553bdcfc80c178a58247f42fb`", `<code class="inline-code-block">88fc37a3c0a4dda553bdcfc80c178a58247f42fb</code>`, false},
+		{"foo `:100:", "foo `:100:", true},
+		{"foo ` :100:", `foo ` + "`" + ` <span class="emoji" aria-label="hundred points">💯</span>`, true},
+		{":100:", `<span class="emoji" aria-label="hundred points">💯</span>`, true},
+		{"#123", `<a href="/user13/repo11/issues/123" class="ref-issue">#123</a>`, false},
+		{"`x`:100:", `<code class="inline-code-block">x</code><span class="emoji" aria-label="hundred points">💯</span>`, true},
+		{"a `:100:` b `:+1:` c", `a <code class="inline-code-block">:100:</code> b <code class="inline-code-block">:+1:</code> c`, true},
+	}
+	for _, c := range cases {
+		assert.Equal(t, c.expected, string(ut.RenderIssueTitle(c.input, mockRepo)), "input=%q", c.input)
+		if c.emojiSafe {
+			assert.Equal(t, c.expected, string(ut.RenderIssueSimpleTitle(c.input)), "simple input=%q", c.input)
+		}
+	}
+}
+
 func TestRenderMarkdownToHtml(t *testing.T) {
 	defer test.MockVariableValue(&markup.RenderBehaviorForTesting.DisableAdditionalAttributes, true)()
 	expected := `<p>space <a href="/mention-user" rel="nofollow">@mention-user</a><br/>