fix(markup): make RenderString never fail (#37779)

Fix #37778

---------

Signed-off-by: wxiaoguang <wxiaoguang@gmail.com>
Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: wxiaoguang <2114189+wxiaoguang@users.noreply.github.com>
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>
Co-authored-by: Nicolas <bircni@icloud.com>

models/renderhelper/main_test.go

@@ -5,12 +5,19 @@ package renderhelper
 
 import (
 	"context"
+	"strings"
 	"testing"
 
 	"code.gitea.io/gitea/models/unittest"
 	"code.gitea.io/gitea/modules/markup"
 )
 
+func testRenderString(ctx *markup.RenderContext, content string) (string, error) {
+	var buf strings.Builder
+	err := markup.Render(ctx, strings.NewReader(content), &buf)
+	return buf.String(), err
+}
+
 func TestMain(m *testing.M) {
 	unittest.MainTest(m, &unittest.TestOptions{
 		FixtureFiles: []string{"repository.yml", "user.yml"},

models/renderhelper/repo_comment_test.go

@@ -8,7 +8,6 @@ import (
 
 	repo_model "code.gitea.io/gitea/models/repo"
 	"code.gitea.io/gitea/models/unittest"
-	"code.gitea.io/gitea/modules/markup"
 	"code.gitea.io/gitea/modules/markup/markdown"
 
 	"github.com/stretchr/testify/assert"
@@ -21,7 +20,7 @@ func TestRepoComment(t *testing.T) {
 
 	t.Run("AutoLink", func(t *testing.T) {
 		rctx := NewRenderContextRepoComment(t.Context(), repo1).WithMarkupType(markdown.MarkupName)
-		rendered, err := markup.RenderString(rctx, `
+		rendered, err := testRenderString(rctx, `
 65f1bf27bc3bf70f64657658635e66094edbcb4d
 #1
 @user2
@@ -39,7 +38,7 @@ func TestRepoComment(t *testing.T) {
 
 		// It is Gitea's old behavior, the relative path is resolved to the repo path
 		// It is different from GitHub, GitHub resolves relative links to current page's path
-		rendered, err := markup.RenderString(rctx, `
+		rendered, err := testRenderString(rctx, `
 [/test](/test)
 [./test](./test)
 ![/image](/image)
@@ -59,7 +58,7 @@ func TestRepoComment(t *testing.T) {
 			WithMarkupType(markdown.MarkupName)
 
 		// the ref path is only used to render commit message: a commit message is rendered at the commit page with its commit ID path
-		rendered, err := markup.RenderString(rctx, `
+		rendered, err := testRenderString(rctx, `
 [/test](/test)
 [./test](./test)
 ![/image](/image)
@@ -75,7 +74,7 @@ func TestRepoComment(t *testing.T) {
 
 	t.Run("NoRepo", func(t *testing.T) {
 		rctx := NewRenderContextRepoComment(t.Context(), nil).WithMarkupType(markdown.MarkupName)
-		rendered, err := markup.RenderString(rctx, "any")
+		rendered, err := testRenderString(rctx, "any")
 		assert.NoError(t, err)
 		assert.Equal(t, "<p>any</p>\n", rendered)
 	})

models/renderhelper/repo_file_test.go

@@ -8,7 +8,6 @@ import (
 
 	repo_model "code.gitea.io/gitea/models/repo"
 	"code.gitea.io/gitea/models/unittest"
-	"code.gitea.io/gitea/modules/markup"
 	"code.gitea.io/gitea/modules/markup/markdown"
 
 	_ "code.gitea.io/gitea/modules/markup/orgmode"
@@ -22,7 +21,7 @@ func TestRepoFile(t *testing.T) {
 
 	t.Run("AutoLink", func(t *testing.T) {
 		rctx := NewRenderContextRepoFile(t.Context(), repo1).WithMarkupType(markdown.MarkupName)
-		rendered, err := markup.RenderString(rctx, `
+		rendered, err := testRenderString(rctx, `
 65f1bf27bc3bf70f64657658635e66094edbcb4d
 #1
 @user2
@@ -38,7 +37,7 @@ func TestRepoFile(t *testing.T) {
 	t.Run("AbsoluteAndRelative", func(t *testing.T) {
 		rctx := NewRenderContextRepoFile(t.Context(), repo1, RepoFileOptions{CurrentRefSubURL: "branch/main"}).
 			WithMarkupType(markdown.MarkupName)
-		rendered, err := markup.RenderString(rctx, `
+		rendered, err := testRenderString(rctx, `
 [/test](/test)
 [./test](./test)
 ![/image](/image)
@@ -56,7 +55,7 @@ func TestRepoFile(t *testing.T) {
 	t.Run("WithCurrentRefSubURL", func(t *testing.T) {
 		rctx := NewRenderContextRepoFile(t.Context(), repo1, RepoFileOptions{CurrentRefSubURL: "/commit/1234"}).
 			WithMarkupType(markdown.MarkupName)
-		rendered, err := markup.RenderString(rctx, `
+		rendered, err := testRenderString(rctx, `
 [/test](/test)
 ![/image](/image)
 `)
@@ -72,7 +71,7 @@ func TestRepoFile(t *testing.T) {
 			CurrentTreePath:  "my-dir",
 		}).
 			WithMarkupType(markdown.MarkupName)
-		rendered, err := markup.RenderString(rctx, `
+		rendered, err := testRenderString(rctx, `
 <img src="LINK">
 <video src="LINK">
 `)
@@ -93,7 +92,7 @@ func TestRepoFileOrgMode(t *testing.T) {
 			CurrentTreePath:  "my-dir",
 		}).WithRelativePath("my-dir/a.org")
 
-		rendered, err := markup.RenderString(rctx, `
+		rendered, err := testRenderString(rctx, `
 [[https://google.com/]]
 [[ImageLink.svg][The Image Desc]]
 `)
@@ -107,7 +106,7 @@ func TestRepoFileOrgMode(t *testing.T) {
 	t.Run("CodeHighlight", func(t *testing.T) {
 		rctx := NewRenderContextRepoFile(t.Context(), repo1, RepoFileOptions{}).WithRelativePath("my-dir/a.org")
 
-		rendered, err := markup.RenderString(rctx, `
+		rendered, err := testRenderString(rctx, `
 #+begin_src c
 int a = 1;
 #+end_src

models/renderhelper/repo_wiki_test.go

@@ -8,7 +8,6 @@ import (
 
 	repo_model "code.gitea.io/gitea/models/repo"
 	"code.gitea.io/gitea/models/unittest"
-	"code.gitea.io/gitea/modules/markup"
 	"code.gitea.io/gitea/modules/markup/markdown"
 
 	"github.com/stretchr/testify/assert"
@@ -20,7 +19,7 @@ func TestRepoWiki(t *testing.T) {
 
 	t.Run("AutoLink", func(t *testing.T) {
 		rctx := NewRenderContextRepoWiki(t.Context(), repo1).WithMarkupType(markdown.MarkupName)
-		rendered, err := markup.RenderString(rctx, `
+		rendered, err := testRenderString(rctx, `
 65f1bf27bc3bf70f64657658635e66094edbcb4d
 #1
 @user2
@@ -35,7 +34,7 @@ func TestRepoWiki(t *testing.T) {
 
 	t.Run("AbsoluteAndRelative", func(t *testing.T) {
 		rctx := NewRenderContextRepoWiki(t.Context(), repo1).WithMarkupType(markdown.MarkupName)
-		rendered, err := markup.RenderString(rctx, `
+		rendered, err := testRenderString(rctx, `
 [/test](/test)
 [./test](./test)
 ![/image](/image)
@@ -52,7 +51,7 @@ func TestRepoWiki(t *testing.T) {
 
 	t.Run("PathInTag", func(t *testing.T) {
 		rctx := NewRenderContextRepoWiki(t.Context(), repo1).WithMarkupType(markdown.MarkupName)
-		rendered, err := markup.RenderString(rctx, `
+		rendered, err := testRenderString(rctx, `
 <img src="LINK">
 <video src="LINK">
 `)

models/renderhelper/simple_document_test.go

@@ -7,7 +7,6 @@ import (
 	"testing"
 
 	"code.gitea.io/gitea/models/unittest"
-	"code.gitea.io/gitea/modules/markup"
 	"code.gitea.io/gitea/modules/markup/markdown"
 
 	"github.com/stretchr/testify/assert"
@@ -16,7 +15,7 @@ import (
 func TestSimpleDocument(t *testing.T) {
 	unittest.PrepareTestEnv(t)
 	rctx := NewRenderContextSimpleDocument(t.Context(), "/base").WithMarkupType(markdown.MarkupName)
-	rendered, err := markup.RenderString(rctx, `
+	rendered, err := testRenderString(rctx, `
 65f1bf27bc3bf70f64657658635e66094edbcb4d
 #1
 @user2

modules/markup/html_codepreview_test.go

@@ -22,7 +22,7 @@ func TestRenderCodePreview(t *testing.T) {
 		},
 	})
 	test := func(input, expected string) {
-		buffer, err := markup.RenderString(markup.NewTestRenderContext().WithMarkupType(markdown.MarkupName), input)
+		buffer, err := testRenderString(markup.NewTestRenderContext().WithMarkupType(markdown.MarkupName), input)
 		assert.NoError(t, err)
 		assert.Equal(t, strings.TrimSpace(expected), strings.TrimSpace(buffer))
 	}

modules/markup/html_test.go

@@ -24,10 +24,16 @@ var (
 	localMetas        = map[string]string{"user": testRepoOwnerName, "repo": testRepoName}
 )
 
+func testRenderString(ctx *markup.RenderContext, content string) (string, error) {
+	var buf strings.Builder
+	err := markup.Render(ctx, strings.NewReader(content), &buf)
+	return buf.String(), err
+}
+
 func TestRender_Commits(t *testing.T) {
 	test := func(input, expected string) {
 		rctx := markup.NewTestRenderContext(markup.TestAppURL, localMetas).WithRelativePath("a.md")
-		buffer, err := markup.RenderString(rctx, input)
+		buffer, err := testRenderString(rctx, input)
 		assert.NoError(t, err)
 		assert.Equal(t, strings.TrimSpace(expected), strings.TrimSpace(buffer))
 	}
@@ -75,7 +81,7 @@ func TestRender_CrossReferences(t *testing.T) {
 	defer testModule.MockVariableValue(&markup.RenderBehaviorForTesting.DisableAdditionalAttributes, true)()
 	test := func(input, expected string) {
 		rctx := markup.NewTestRenderContext(markup.TestAppURL, localMetas).WithRelativePath("a.md")
-		buffer, err := markup.RenderString(rctx, input)
+		buffer, err := testRenderString(rctx, input)
 		assert.NoError(t, err)
 		assert.Equal(t, strings.TrimSpace(expected), strings.TrimSpace(buffer))
 	}
@@ -119,7 +125,7 @@ func TestRender_links(t *testing.T) {
 	setting.AppURL = markup.TestAppURL
 	defer testModule.MockVariableValue(&markup.RenderBehaviorForTesting.DisableAdditionalAttributes, true)()
 	test := func(input, expected string) {
-		buffer, err := markup.RenderString(markup.NewTestRenderContext().WithRelativePath("a.md"), input)
+		buffer, err := testRenderString(markup.NewTestRenderContext().WithRelativePath("a.md"), input)
 		assert.NoError(t, err)
 		assert.Equal(t, strings.TrimSpace(expected), strings.TrimSpace(buffer))
 	}
@@ -234,7 +240,7 @@ func TestRender_email(t *testing.T) {
 	setting.AppURL = markup.TestAppURL
 	defer testModule.MockVariableValue(&markup.RenderBehaviorForTesting.DisableAdditionalAttributes, true)()
 	test := func(input, expected string) {
-		res, err := markup.RenderString(markup.NewTestRenderContext().WithRelativePath("a.md"), input)
+		res, err := testRenderString(markup.NewTestRenderContext().WithRelativePath("a.md"), input)
 		assert.NoError(t, err)
 		assert.Equal(t, strings.TrimSpace(expected), strings.TrimSpace(res), "input: %s", input)
 	}
@@ -321,7 +327,7 @@ func TestRender_emoji(t *testing.T) {
 
 	test := func(input, expected string) {
 		expected = strings.ReplaceAll(expected, "&", "&")
-		buffer, err := markup.RenderString(markup.NewTestRenderContext().WithRelativePath("a.md"), input)
+		buffer, err := testRenderString(markup.NewTestRenderContext().WithRelativePath("a.md"), input)
 		assert.NoError(t, err)
 		assert.Equal(t, strings.TrimSpace(expected), strings.TrimSpace(buffer))
 	}

modules/markup/markdown/markdown.go

@@ -11,6 +11,7 @@ import (
 	"io"
 	"strings"
 
+	"code.gitea.io/gitea/modules/htmlutil"
 	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/markup"
 	"code.gitea.io/gitea/modules/markup/common"
@@ -266,7 +267,9 @@ func Render(ctx *markup.RenderContext, input io.Reader, output io.Writer) error
 func RenderString(ctx *markup.RenderContext, content string) (template.HTML, error) {
 	var buf strings.Builder
 	if err := Render(ctx, strings.NewReader(content), &buf); err != nil {
-		return "", err
+		log.Warn("Unable to RenderString: %v, content: %s", err, giteautil.TruncateRunes(content, 200))
+		err = nil
+		return htmlutil.EscapeString(content), err
 	}
 	return template.HTML(buf.String()), nil
 }

modules/markup/render.go

@@ -198,15 +198,6 @@ func Render(rctx *RenderContext, origInput io.Reader, output io.Writer) error {
 	return RenderWithRenderer(rctx, renderer, input, output)
 }
 
-// RenderString renders Markup string to HTML with all specific handling stuff and return string
-func RenderString(ctx *RenderContext, content string) (string, error) {
-	var buf strings.Builder
-	if err := Render(ctx, strings.NewReader(content), &buf); err != nil {
-		return "", err
-	}
-	return buf.String(), nil
-}
-
 func RenderIFrame(ctx *RenderContext, opts *ExternalRendererOptions, output io.Writer) error {
 	ownerName, repoName := ctx.RenderOptions.Metas["user"], ctx.RenderOptions.Metas["repo"]
 	refSubURL := ctx.RenderOptions.Metas["RefTypeNameSubURL"]