Fix issue title rendering and refactor legacy function names (#32703)

Fix #32700, regression of recent markup refactoring

And by the way, clarify many legacy problems:

1. Some "RenderXxx" functions do not really "render", they only call "post processors"
2. Merge "RenderEmoji | RenderCodeBlock", they are all for "simple issue title"

5 files changed, 50 insertions, 34 deletions

diff --git a/modules/markup/html.go b/modules/markup/html.go
index 04b768bb8e..25628db39e 100644
--- a/modules/markup/html.go
+++ b/modules/markup/html.go
@@ -159,9 +159,9 @@ func PostProcessDefault(ctx *RenderContext, input io.Reader, output io.Writer) e
 	return postProcess(ctx, procs, input, output)
 }
 
-// RenderCommitMessage will use the same logic as PostProcess, but will disable
+// PostProcessCommitMessage will use the same logic as PostProcess, but will disable
 // the shortLinkProcessor.
-func RenderCommitMessage(ctx *RenderContext, content string) (string, error) {
+func PostProcessCommitMessage(ctx *RenderContext, content string) (string, error) {
 	procs := []processor{
 		fullIssuePatternProcessor,
 		comparePatternProcessor,
@@ -183,11 +183,11 @@ var emojiProcessors = []processor{
 	emojiProcessor,
 }
 
-// RenderCommitMessageSubject will use the same logic as PostProcess and
-// RenderCommitMessage, but will disable the shortLinkProcessor and
+// PostProcessCommitMessageSubject will use the same logic as PostProcess and
+// PostProcessCommitMessage, but will disable the shortLinkProcessor and
 // emailAddressProcessor, will add a defaultLinkProcessor if defaultLink is set,
 // which changes every text node into a link to the passed default link.
-func RenderCommitMessageSubject(ctx *RenderContext, defaultLink, content string) (string, error) {
+func PostProcessCommitMessageSubject(ctx *RenderContext, defaultLink, content string) (string, error) {
 	procs := []processor{
 		fullIssuePatternProcessor,
 		comparePatternProcessor,
@@ -211,26 +211,20 @@ func RenderCommitMessageSubject(ctx *RenderContext, defaultLink, content string)
 	return postProcessString(ctx, procs, content)
 }
 
-// RenderIssueTitle to process title on individual issue/pull page
-func RenderIssueTitle(ctx *RenderContext, title string) (string, error) {
-	// do not render other issue/commit links in an issue's title - which in most cases is already a link.
+// PostProcessIssueTitle to process title on individual issue/pull page
+func PostProcessIssueTitle(ctx *RenderContext, title string) (string, error) {
 	return postProcessString(ctx, []processor{
+		issueIndexPatternProcessor,
+		commitCrossReferencePatternProcessor,
+		hashCurrentPatternProcessor,
 		emojiShortCodeProcessor,
 		emojiProcessor,
 	}, title)
 }
 
-func postProcessString(ctx *RenderContext, procs []processor, content string) (string, error) {
-	var buf strings.Builder
-	if err := postProcess(ctx, procs, strings.NewReader(content), &buf); err != nil {
-		return "", err
-	}
-	return buf.String(), nil
-}
-
-// RenderDescriptionHTML will use similar logic as PostProcess, but will
+// PostProcessDescriptionHTML will use similar logic as PostProcess, but will
 // use a single special linkProcessor.
-func RenderDescriptionHTML(ctx *RenderContext, content string) (string, error) {
+func PostProcessDescriptionHTML(ctx *RenderContext, content string) (string, error) {
 	return postProcessString(ctx, []processor{
 		descriptionLinkProcessor,
 		emojiShortCodeProcessor,
@@ -238,13 +232,24 @@ func RenderDescriptionHTML(ctx *RenderContext, content string) (string, error) {
 	}, content)
 }
 
-// RenderEmoji for when we want to just process emoji and shortcodes
+// PostProcessEmoji for when we want to just process emoji and shortcodes
 // in various places it isn't already run through the normal markdown processor
-func RenderEmoji(ctx *RenderContext, content string) (string, error) {
+func PostProcessEmoji(ctx *RenderContext, content string) (string, error) {
 	return postProcessString(ctx, emojiProcessors, content)
 }
 
+func postProcessString(ctx *RenderContext, procs []processor, content string) (string, error) {
+	var buf strings.Builder
+	if err := postProcess(ctx, procs, strings.NewReader(content), &buf); err != nil {
+		return "", err
+	}
+	return buf.String(), nil
+}
+
 func postProcess(ctx *RenderContext, procs []processor, input io.Reader, output io.Writer) error {
+	if !ctx.usedByRender && ctx.RenderHelper != nil {
+		defer ctx.RenderHelper.CleanUp()
+	}
 	// FIXME: don't read all content to memory
 	rawHTML, err := io.ReadAll(input)
 	if err != nil {
diff --git a/modules/markup/html_internal_test.go b/modules/markup/html_internal_test.go
index 651e674108..9419350e61 100644
--- a/modules/markup/html_internal_test.go
+++ b/modules/markup/html_internal_test.go
@@ -252,7 +252,7 @@ func TestRender_IssueIndexPattern_NoShortPattern(t *testing.T) {
 	testRenderIssueIndexPattern(t, "!1", "!1", NewTestRenderContext(metas))
 }
 
-func TestRender_RenderIssueTitle(t *testing.T) {
+func TestRender_PostProcessIssueTitle(t *testing.T) {
 	setting.AppURL = TestAppURL
 	metas := map[string]string{
 		"format": "https://someurl.com/{user}/{repo}/{index}",
@@ -260,7 +260,7 @@ func TestRender_RenderIssueTitle(t *testing.T) {
 		"repo":   "someRepo",
 		"style":  IssueNameStyleNumeric,
 	}
-	actual, err := RenderIssueTitle(NewTestRenderContext(metas), "#1")
+	actual, err := PostProcessIssueTitle(NewTestRenderContext(metas), "#1")
 	assert.NoError(t, err)
 	assert.Equal(t, "#1", actual)
 }
diff --git a/modules/markup/render.go b/modules/markup/render.go
index 3b112b1a14..b239e59687 100644
--- a/modules/markup/render.go
+++ b/modules/markup/render.go
@@ -57,6 +57,9 @@ type RenderOptions struct {
 type RenderContext struct {
 	ctx context.Context
 
+	// the context might be used by the "render" function, but it might also be used by "postProcess" function
+	usedByRender bool
+
 	SidebarTocNode ast.Node
 
 	RenderHelper   RenderHelper
@@ -182,6 +185,7 @@ func pipes() (io.ReadCloser, io.WriteCloser, func()) {
 }
 
 func render(ctx *RenderContext, renderer Renderer, input io.Reader, output io.Writer) error {
+	ctx.usedByRender = true
 	if ctx.RenderHelper != nil {
 		defer ctx.RenderHelper.CleanUp()
 	}
diff --git a/modules/templates/util_render.go b/modules/templates/util_render.go
index 3237de5ecb..1800747f48 100644
--- a/modules/templates/util_render.go
+++ b/modules/templates/util_render.go
@@ -38,9 +38,9 @@ func (ut *RenderUtils) RenderCommitMessage(msg string, metas map[string]string)
 	cleanMsg := template.HTMLEscapeString(msg)
 	// we can safely assume that it will not return any error, since there
 	// shouldn't be any special HTML.
-	fullMessage, err := markup.RenderCommitMessage(markup.NewRenderContext(ut.ctx).WithMetas(metas), cleanMsg)
+	fullMessage, err := markup.PostProcessCommitMessage(markup.NewRenderContext(ut.ctx).WithMetas(metas), cleanMsg)
 	if err != nil {
-		log.Error("RenderCommitMessage: %v", err)
+		log.Error("PostProcessCommitMessage: %v", err)
 		return ""
 	}
 	msgLines := strings.Split(strings.TrimSpace(fullMessage), "\n")
@@ -65,9 +65,9 @@ func (ut *RenderUtils) RenderCommitMessageLinkSubject(msg, urlDefault string, me
 
 	// we can safely assume that it will not return any error, since there
 	// shouldn't be any special HTML.
-	renderedMessage, err := markup.RenderCommitMessageSubject(markup.NewRenderContext(ut.ctx).WithMetas(metas), urlDefault, template.HTMLEscapeString(msgLine))
+	renderedMessage, err := markup.PostProcessCommitMessageSubject(markup.NewRenderContext(ut.ctx).WithMetas(metas), urlDefault, template.HTMLEscapeString(msgLine))
 	if err != nil {
-		log.Error("RenderCommitMessageSubject: %v", err)
+		log.Error("PostProcessCommitMessageSubject: %v", err)
 		return ""
 	}
 	return renderCodeBlock(template.HTML(renderedMessage))
@@ -87,9 +87,9 @@ func (ut *RenderUtils) RenderCommitBody(msg string, metas map[string]string) tem
 		return ""
 	}
 
-	renderedMessage, err := markup.RenderCommitMessage(markup.NewRenderContext(ut.ctx).WithMetas(metas), template.HTMLEscapeString(msgLine))
+	renderedMessage, err := markup.PostProcessCommitMessage(markup.NewRenderContext(ut.ctx).WithMetas(metas), template.HTMLEscapeString(msgLine))
 	if err != nil {
-		log.Error("RenderCommitMessage: %v", err)
+		log.Error("PostProcessCommitMessage: %v", err)
 		return ""
 	}
 	return template.HTML(renderedMessage)
@@ -106,12 +106,19 @@ func renderCodeBlock(htmlEscapedTextToRender template.HTML) template.HTML {
 
 // RenderIssueTitle renders issue/pull title with defined post processors
 func (ut *RenderUtils) RenderIssueTitle(text string, metas map[string]string) template.HTML {
-	renderedText, err := markup.RenderIssueTitle(markup.NewRenderContext(ut.ctx).WithMetas(metas), template.HTMLEscapeString(text))
+	renderedText, err := markup.PostProcessIssueTitle(markup.NewRenderContext(ut.ctx).WithMetas(metas), template.HTMLEscapeString(text))
 	if err != nil {
-		log.Error("RenderIssueTitle: %v", err)
+		log.Error("PostProcessIssueTitle: %v", err)
 		return ""
 	}
-	return template.HTML(renderedText)
+	return renderCodeBlock(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
 }
 
 // RenderLabel renders a label
@@ -174,7 +181,7 @@ func (ut *RenderUtils) RenderLabel(label *issues_model.Label) template.HTML {
 
 // RenderEmoji renders html text with emoji post processors
 func (ut *RenderUtils) RenderEmoji(text string) template.HTML {
-	renderedText, err := markup.RenderEmoji(markup.NewRenderContext(ut.ctx), template.HTMLEscapeString(text))
+	renderedText, err := markup.PostProcessEmoji(markup.NewRenderContext(ut.ctx), template.HTMLEscapeString(text))
 	if err != nil {
 		log.Error("RenderEmoji: %v", err)
 		return ""
diff --git a/modules/templates/util_render_test.go b/modules/templates/util_render_test.go
index c0241c0a8c..80094ab26e 100644
--- a/modules/templates/util_render_test.go
+++ b/modules/templates/util_render_test.go
@@ -164,11 +164,11 @@ com 88fc37a3c0a4dda553bdcfc80c178a58247f42fb mit
 <span class="emoji" aria-label="thumbs up">👍</span>
 mail@domain.com
 @mention-user test
-#123
+<a href="/user13/repo11/issues/123" class="ref-issue">#123</a>
   space<SPACE><SPACE>
 `
 	expected = strings.ReplaceAll(expected, "<SPACE>", " ")
-	assert.EqualValues(t, expected, string(newTestRenderUtils().RenderIssueTitle(testInput(), nil)))
+	assert.EqualValues(t, expected, string(newTestRenderUtils().RenderIssueTitle(testInput(), testMetas)))
 }
 
 func TestRenderMarkdownToHtml(t *testing.T) {