Markdown rendering overhaul (#186)

* Markdown rendering overhaul

Cleaned up and squashed commits into single one.

Signed-off-by: Andrew Boyarshin <boyarshinand@gmail.com>

* Fix markdown API, add markdown module and API tests, improve code coverage

Signed-off-by: Andrew Boyarshin <boyarshinand@gmail.com>

2 files changed, 871 insertions, 138 deletions

diff --git a/modules/markdown/markdown.go b/modules/markdown/markdown.go
index c0b7c91f83..5218af8f27 100644
--- a/modules/markdown/markdown.go
+++ b/modules/markdown/markdown.go
@@ -8,6 +8,7 @@ import (
 	"bytes"
 	"fmt"
 	"io"
+	"net/url"
 	"path"
 	"path/filepath"
 	"regexp"
@@ -35,23 +36,17 @@ var Sanitizer = bluemonday.UGCPolicy()
 // This function should only be called once during entire application lifecycle.
 func BuildSanitizer() {
 	// Normal markdown-stuff
-	Sanitizer.AllowAttrs("class").Matching(regexp.MustCompile(`[\p{L}\p{N}\s\-_',:\[\]!\./\\\(\)&]*`)).OnElements("code")
+	Sanitizer.AllowAttrs("class").Matching(regexp.MustCompile(`[\p{L}\p{N}\s\-_',:\[\]!\./\\\(\)&]*`)).OnElements("code", "div", "ul", "ol", "dl")
 
 	// Checkboxes
 	Sanitizer.AllowAttrs("type").Matching(regexp.MustCompile(`^checkbox$`)).OnElements("input")
 	Sanitizer.AllowAttrs("checked", "disabled").OnElements("input")
+	Sanitizer.AllowNoAttrs().OnElements("label")
 
 	// Custom URL-Schemes
 	Sanitizer.AllowURLSchemes(setting.Markdown.CustomURLSchemes...)
 }
 
-var validLinksPattern = regexp.MustCompile(`^[a-z][\w-]+://`)
-
-// isLink reports whether link fits valid format.
-func isLink(link []byte) bool {
-	return validLinksPattern.Match(link)
-}
-
 // IsMarkdownFile reports whether name looks like a Markdown file
 // based on its extension.
 func IsMarkdownFile(name string) bool {
@@ -65,7 +60,7 @@ func IsMarkdownFile(name string) bool {
 }
 
 // IsReadmeFile reports whether name looks like a README file
-// based on its extension.
+// based on its name.
 func IsReadmeFile(name string) bool {
 	name = strings.ToLower(name)
 	if len(name) < 6 {
@@ -80,13 +75,6 @@ var (
 	// MentionPattern matches string that mentions someone, e.g. @Unknwon
 	MentionPattern = regexp.MustCompile(`(\s|^|\W)@[0-9a-zA-Z-_\.]+`)
 
-	// CommitPattern matches link to certain commit with or without trailing hash,
-	// e.g. https://try.gogs.io/gogs/gogs/commit/d8a994ef243349f321568f9e36d5c3f444b99cae#diff-2
-	CommitPattern = regexp.MustCompile(`(\s|^)https?.*commit/[0-9a-zA-Z]+(#+[0-9a-zA-Z-]*)?`)
-
-	// IssueFullPattern matches link to an issue with or without trailing hash,
-	// e.g. https://try.gogs.io/gogs/gogs/issues/4#issue-685
-	IssueFullPattern = regexp.MustCompile(`(\s|^)https?.*issues/[0-9]+(#+[0-9a-zA-Z-]*)?`)
 	// IssueNumericPattern matches string that references to a numeric issue, e.g. #1287
 	IssueNumericPattern = regexp.MustCompile(`( |^|\()#[0-9]+\b`)
 	// IssueAlphanumericPattern matches string that references to an alphanumeric issue, e.g. ABC-1234
@@ -96,11 +84,27 @@ var (
 	CrossReferenceIssueNumericPattern = regexp.MustCompile(`( |^)[0-9a-zA-Z]+/[0-9a-zA-Z]+#[0-9]+\b`)
 
 	// Sha1CurrentPattern matches string that represents a commit SHA, e.g. d8a994ef243349f321568f9e36d5c3f444b99cae
-	// FIXME: this pattern matches pure numbers as well, right now we do a hack to check in RenderSha1CurrentPattern
+	// FIXME: this pattern matches pure numbers as well, right now we do a hack to check in renderSha1CurrentPattern
 	// by converting string to a number.
-	Sha1CurrentPattern = regexp.MustCompile(`\b[0-9a-f]{40}\b`)
+	Sha1CurrentPattern = regexp.MustCompile(`(?:^|\s|\()[0-9a-f]{40}\b`)
+
+	// ShortLinkPattern matches short but difficult to parse [[name|link|arg=test]] syntax
+	ShortLinkPattern = regexp.MustCompile(`(\[\[.*\]\]\w*)`)
+
+	// AnySHA1Pattern allows to split url containing SHA into parts
+	AnySHA1Pattern = regexp.MustCompile(`http\S+//(\S+)/(\S+)/(\S+)/(\S+)/([0-9a-f]{40})(?:/?([^#\s]+)?(?:#(\S+))?)?`)
+
+	// IssueFullPattern allows to split issue (and pull) URLs into parts
+	IssueFullPattern = regexp.MustCompile(`(?:^|\s|\()http\S+//((?:[^\s/]+/)+)((?:\w{1,10}-)?[1-9][0-9]*)([\?|#]\S+.(\S+)?)?\b`)
+
+	validLinksPattern = regexp.MustCompile(`^[a-z][\w-]+://`)
 )
 
+// isLink reports whether link fits valid format.
+func isLink(link []byte) bool {
+	return validLinksPattern.Match(link)
+}
+
 // FindAllMentions matches mention patterns in given content
 // and returns a list of found user names without @ prefix.
 func FindAllMentions(content string) []string {
@@ -114,79 +118,67 @@ func FindAllMentions(content string) []string {
 // Renderer is a extended version of underlying render object.
 type Renderer struct {
 	blackfriday.Renderer
-	urlPrefix string
+	urlPrefix      string
+	isWikiMarkdown bool
 }
 
 // Link defines how formal links should be processed to produce corresponding HTML elements.
 func (r *Renderer) Link(out *bytes.Buffer, link []byte, title []byte, content []byte) {
 	if len(link) > 0 && !isLink(link) {
 		if link[0] != '#' {
-			link = []byte(path.Join(r.urlPrefix, string(link)))
+			mLink := URLJoin(r.urlPrefix, string(link))
+			if r.isWikiMarkdown {
+				mLink = URLJoin(r.urlPrefix, "wiki", string(link))
+			}
+			link = []byte(mLink)
 		}
 	}
 
 	r.Renderer.Link(out, link, title, content)
 }
 
-// AutoLink defines how auto-detected links should be processed to produce corresponding HTML elements.
-// Reference for kind: https://github.com/russross/blackfriday/blob/master/markdown.go#L69-L76
-func (r *Renderer) AutoLink(out *bytes.Buffer, link []byte, kind int) {
-	if kind != blackfriday.LINK_TYPE_NORMAL {
-		r.Renderer.AutoLink(out, link, kind)
-		return
+// List renders markdown bullet or digit lists to HTML
+func (r *Renderer) List(out *bytes.Buffer, text func() bool, flags int) {
+	marker := out.Len()
+	if out.Len() > 0 {
+		out.WriteByte('\n')
 	}
 
-	// Since this method could only possibly serve one link at a time,
-	// we do not need to find all.
-	if bytes.HasPrefix(link, []byte(setting.AppURL)) {
-		m := CommitPattern.Find(link)
-		if m != nil {
-			m = bytes.TrimSpace(m)
-			i := strings.Index(string(m), "commit/")
-			j := strings.Index(string(m), "#")
-			if j == -1 {
-				j = len(m)
-			}
-			out.WriteString(fmt.Sprintf(` <code><a href="%s">%s</a></code>`, m, base.ShortSha(string(m[i+7:j]))))
-			return
-		}
-
-		m = IssueFullPattern.Find(link)
-		if m != nil {
-			m = bytes.TrimSpace(m)
-			i := strings.Index(string(m), "issues/")
-			j := strings.Index(string(m), "#")
-			if j == -1 {
-				j = len(m)
-			}
-
-			issue := string(m[i+7 : j])
-			fullRepoURL := setting.AppURL + strings.TrimPrefix(r.urlPrefix, "/")
-			var link string
-			if strings.HasPrefix(string(m), fullRepoURL) {
-				// Use a short issue reference if the URL refers to this repository
-				link = fmt.Sprintf(`<a href="%s">#%s</a>`, m, issue)
-			} else {
-				// Use a cross-repository issue reference if the URL refers to a different repository
-				repo := string(m[len(setting.AppURL) : i-1])
-				link = fmt.Sprintf(`<a href="%s">%s#%s</a>`, m, repo, issue)
-			}
-			out.WriteString(link)
-			return
-		}
+	if flags&blackfriday.LIST_TYPE_DEFINITION != 0 {
+		out.WriteString("<dl>")
+	} else if flags&blackfriday.LIST_TYPE_ORDERED != 0 {
+		out.WriteString("<ol class='ui list'>")
+	} else {
+		out.WriteString("<ul class='ui list'>")
+	}
+	if !text() {
+		out.Truncate(marker)
+		return
+	}
+	if flags&blackfriday.LIST_TYPE_DEFINITION != 0 {
+		out.WriteString("</dl>\n")
+	} else if flags&blackfriday.LIST_TYPE_ORDERED != 0 {
+		out.WriteString("</ol>\n")
+	} else {
+		out.WriteString("</ul>\n")
 	}
-
-	r.Renderer.AutoLink(out, link, kind)
 }
 
 // ListItem defines how list items should be processed to produce corresponding HTML elements.
 func (r *Renderer) ListItem(out *bytes.Buffer, text []byte, flags int) {
 	// Detect procedures to draw checkboxes.
+	prefix := ""
+	if bytes.HasPrefix(text, []byte("<p>")) {
+		prefix = "<p>"
+	}
 	switch {
-	case bytes.HasPrefix(text, []byte("[ ] ")):
-		text = append([]byte(`<input type="checkbox" disabled="" />`), text[3:]...)
-	case bytes.HasPrefix(text, []byte("[x] ")):
-		text = append([]byte(`<input type="checkbox" disabled="" checked="" />`), text[3:]...)
+	case bytes.HasPrefix(text, []byte(prefix+"[ ] ")):
+		text = append([]byte(`<div class="ui fitted disabled checkbox"><input type="checkbox" disabled="disabled" /><label /></div>`), text[3+len(prefix):]...)
+	case bytes.HasPrefix(text, []byte(prefix+"[x] ")):
+		text = append([]byte(`<div class="ui checked fitted disabled checkbox"><input type="checkbox" checked="" disabled="disabled" /><label /></div>`), text[3+len(prefix):]...)
+	}
+	if prefix != "" {
+		text = bytes.Replace(text, []byte("</p>"), []byte{}, 1)
 	}
 	r.Renderer.ListItem(out, text, flags)
 }
@@ -196,15 +188,15 @@ func (r *Renderer) ListItem(out *bytes.Buffer, text []byte, flags int) {
 var (
 	svgSuffix         = []byte(".svg")
 	svgSuffixWithMark = []byte(".svg?")
-	spaceBytes        = []byte(" ")
-	spaceEncodedBytes = []byte("%20")
-	space             = " "
-	spaceEncoded      = "%20"
 )
 
 // Image defines how images should be processed to produce corresponding HTML elements.
 func (r *Renderer) Image(out *bytes.Buffer, link []byte, title []byte, alt []byte) {
-	prefix := strings.Replace(r.urlPrefix, "/src/", "/raw/", 1)
+	prefix := r.urlPrefix
+	if r.isWikiMarkdown {
+		prefix = URLJoin(prefix, "wiki", "src")
+	}
+	prefix = strings.Replace(prefix, "/src/", "/raw/", 1)
 	if len(link) > 0 {
 		if isLink(link) {
 			// External link with .svg suffix usually means CI status.
@@ -215,10 +207,11 @@ func (r *Renderer) Image(out *bytes.Buffer, link []byte, title []byte, alt []byt
 			}
 		} else {
 			if link[0] != '/' {
-				prefix += "/"
+				if !strings.HasSuffix(prefix, "/") {
+					prefix += "/"
+				}
 			}
-			link = bytes.Replace([]byte((prefix + string(link))), spaceBytes, spaceEncodedBytes, -1)
-			fmt.Println(333, string(link))
+			link = []byte(url.QueryEscape(prefix + string(link)))
 		}
 	}
 
@@ -247,6 +240,19 @@ func cutoutVerbosePrefix(prefix string) string {
 	return prefix
 }
 
+// URLJoin joins url components, like path.Join, but preserving contents
+func URLJoin(elem ...string) string {
+	res := ""
+	last := len(elem) - 1
+	for i, item := range elem {
+		res += item
+		if !strings.HasSuffix(res, "/") && i != last {
+			res += "/"
+		}
+	}
+	return res
+}
+
 // RenderIssueIndexPattern renders issue indexes to corresponding links.
 func RenderIssueIndexPattern(rawBytes []byte, urlPrefix string, metas map[string]string) []byte {
 	urlPrefix = cutoutVerbosePrefix(urlPrefix)
@@ -263,7 +269,7 @@ func RenderIssueIndexPattern(rawBytes []byte, urlPrefix string, metas map[string
 		}
 		var link string
 		if metas == nil {
-			link = fmt.Sprintf(`<a href="%s/issues/%s">%s</a>`, urlPrefix, m[1:], m)
+			link = fmt.Sprintf(`<a href="%s">%s</a>`, URLJoin(urlPrefix, "issues", string(m[1:])), m)
 		} else {
 			// Support for external issue tracker
 			if metas["style"] == IssueNameStyleAlphanumeric {
@@ -278,6 +284,238 @@ func RenderIssueIndexPattern(rawBytes []byte, urlPrefix string, metas map[string
 	return rawBytes
 }
 
+// IsSameDomain checks if given url string has the same hostname as current Gitea instance
+func IsSameDomain(s string) bool {
+	if uapp, err := url.Parse(setting.AppURL); err == nil {
+		if u, err := url.Parse(s); err == nil {
+			return u.Host == uapp.Host
+		}
+		return false
+	}
+	return false
+}
+
+// renderFullSha1Pattern renders SHA containing URLs
+func renderFullSha1Pattern(rawBytes []byte, urlPrefix string) []byte {
+	ms := AnySHA1Pattern.FindAllSubmatch(rawBytes, -1)
+	for _, m := range ms {
+		all := m[0]
+		paths := string(m[1])
+		var path = "//" + paths
+		author := string(m[2])
+		repoName := string(m[3])
+		path = URLJoin(path, author, repoName)
+		ltype := "src"
+		itemType := m[4]
+		if IsSameDomain(paths) {
+			ltype = string(itemType)
+		} else if string(itemType) == "commit" {
+			ltype = "commit"
+		}
+		sha := m[5]
+		var subtree string
+		if len(m) > 6 && len(m[6]) > 0 {
+			subtree = string(m[6])
+		}
+		var line []byte
+		if len(m) > 7 && len(m[7]) > 0 {
+			line = m[7]
+		}
+		urlSuffix := ""
+		text := base.ShortSha(string(sha))
+		if subtree != "" {
+			urlSuffix = "/" + subtree
+			text += urlSuffix
+		}
+		if line != nil {
+			value := string(line)
+			urlSuffix += "#"
+			urlSuffix += value
+			text += " ("
+			text += value
+			text += ")"
+		}
+		rawBytes = bytes.Replace(rawBytes, all, []byte(fmt.Sprintf(
+			`<a href="%s">%s</a>`, URLJoin(path, ltype, string(sha))+urlSuffix, text)), -1)
+	}
+	return rawBytes
+}
+
+// renderFullIssuePattern renders issues-like URLs
+func renderFullIssuePattern(rawBytes []byte, urlPrefix string) []byte {
+	ms := IssueFullPattern.FindAllSubmatch(rawBytes, -1)
+	for _, m := range ms {
+		all := m[0]
+		paths := bytes.Split(m[1], []byte("/"))
+		paths = paths[:len(paths)-1]
+		if bytes.HasPrefix(paths[0], []byte("gist.")) {
+			continue
+		}
+		var path string
+		if len(paths) > 3 {
+			// Internal one
+			path = URLJoin(urlPrefix, "issues")
+		} else {
+			path = "//" + string(m[1])
+		}
+		id := string(m[2])
+		path = URLJoin(path, id)
+		var comment []byte
+		if len(m) > 3 {
+			comment = m[3]
+		}
+		urlSuffix := ""
+		text := "#" + id
+		if comment != nil {
+			urlSuffix += string(comment)
+			text += " <i class='comment icon'></i>"
+		}
+		rawBytes = bytes.Replace(rawBytes, all, []byte(fmt.Sprintf(
+			`<a href="%s%s">%s</a>`, path, urlSuffix, text)), -1)
+	}
+	return rawBytes
+}
+
+func firstIndexOfByte(sl []byte, target byte) int {
+	for i := 0; i < len(sl); i++ {
+		if sl[i] == target {
+			return i
+		}
+	}
+	return -1
+}
+
+func lastIndexOfByte(sl []byte, target byte) int {
+	for i := len(sl) - 1; i >= 0; i-- {
+		if sl[i] == target {
+			return i
+		}
+	}
+	return -1
+}
+
+// renderShortLinks processes [[syntax]]
+func renderShortLinks(rawBytes []byte, urlPrefix string, noLink bool) []byte {
+	ms := ShortLinkPattern.FindAll(rawBytes, -1)
+	for _, m := range ms {
+		orig := bytes.TrimSpace(m)
+		m = orig[2:]
+		tailPos := lastIndexOfByte(m, ']') + 1
+		tail := []byte{}
+		if tailPos < len(m) {
+			tail = m[tailPos:]
+			m = m[:tailPos-1]
+		}
+		m = m[:len(m)-2]
+		props := map[string]string{}
+
+		// MediaWiki uses [[link|text]], while GitHub uses [[text|link]]
+		// It makes page handling terrible, but we prefer GitHub syntax
+		// And fall back to MediaWiki only when it is obvious from the look
+		// Of text and link contents
+		sl := bytes.Split(m, []byte("|"))
+		for _, v := range sl {
+			switch bytes.Count(v, []byte("=")) {
+
+			// Piped args without = sign, these are mandatory arguments
+			case 0:
+				{
+					sv := string(v)
+					if props["name"] == "" {
+						if isLink(v) {
+							// If we clearly see it is a link, we save it so
+
+							// But first we need to ensure, that if both mandatory args provided
+							// look like links, we stick to GitHub syntax
+							if props["link"] != "" {
+								props["name"] = props["link"]
+							}
+
+							props["link"] = strings.TrimSpace(sv)
+						} else {
+							props["name"] = sv
+						}
+					} else {
+						props["link"] = strings.TrimSpace(sv)
+					}
+				}
+
+			// Piped args with = sign, these are optional arguments
+			case 1:
+				{
+					sep := firstIndexOfByte(v, '=')
+					key, val := string(v[:sep]), html.UnescapeString(string(v[sep+1:]))
+					lastCharIndex := len(val) - 1
+					if (val[0] == '"' || val[0] == '\'') && (val[lastCharIndex] == '"' || val[lastCharIndex] == '\'') {
+						val = val[1:lastCharIndex]
+					}
+					props[key] = val
+				}
+			}
+		}
+
+		var name string
+		var link string
+		if props["link"] != "" {
+			link = props["link"]
+		} else if props["name"] != "" {
+			link = props["name"]
+		}
+		if props["title"] != "" {
+			name = props["title"]
+		} else if props["name"] != "" {
+			name = props["name"]
+		} else {
+			name = link
+		}
+
+		name += string(tail)
+		image := false
+		ext := filepath.Ext(string(link))
+		if ext != "" {
+			switch ext {
+			case ".jpg", ".jpeg", ".png", ".tif", ".tiff", ".webp", ".gif", ".bmp", ".ico", ".svg":
+				{
+					image = true
+				}
+			}
+		}
+		absoluteLink := isLink([]byte(link))
+		if !absoluteLink {
+			link = url.QueryEscape(link)
+		}
+		if image {
+			if !absoluteLink {
+				link = URLJoin(urlPrefix, "wiki", "raw", link)
+			}
+			title := props["title"]
+			if title == "" {
+				title = props["alt"]
+			}
+			if title == "" {
+				title = path.Base(string(name))
+			}
+			alt := props["alt"]
+			if alt == "" {
+				alt = name
+			}
+			if alt != "" {
+				alt = `alt="` + alt + `"`
+			}
+			name = fmt.Sprintf(`<img src="%s" %s title="%s" />`, link, alt, title)
+		} else if !absoluteLink {
+			link = URLJoin(urlPrefix, "wiki", link)
+		}
+		if noLink {
+			rawBytes = bytes.Replace(rawBytes, orig, []byte(name), -1)
+		} else {
+			rawBytes = bytes.Replace(rawBytes, orig,
+				[]byte(fmt.Sprintf(`<a href="%s">%s</a>`, link, name)), -1)
+		}
+	}
+	return rawBytes
+}
+
 // RenderCrossReferenceIssueIndexPattern renders issue indexes from other repositories to corresponding links.
 func RenderCrossReferenceIssueIndexPattern(rawBytes []byte, urlPrefix string, metas map[string]string) []byte {
 	ms := CrossReferenceIssueNumericPattern.FindAll(rawBytes, -1)
@@ -289,20 +527,24 @@ func RenderCrossReferenceIssueIndexPattern(rawBytes []byte, urlPrefix string, me
 		repo := string(bytes.Split(m, []byte("#"))[0])
 		issue := string(bytes.Split(m, []byte("#"))[1])
 
-		link := fmt.Sprintf(`<a href="%s%s/issues/%s">%s</a>`, setting.AppURL, repo, issue, m)
+		link := fmt.Sprintf(`<a href="%s">%s</a>`, URLJoin(urlPrefix, repo, "issues", issue), m)
 		rawBytes = bytes.Replace(rawBytes, m, []byte(link), 1)
 	}
 	return rawBytes
 }
 
-// RenderSha1CurrentPattern renders SHA1 strings to corresponding links that assumes in the same repository.
-func RenderSha1CurrentPattern(rawBytes []byte, urlPrefix string) []byte {
-	return []byte(Sha1CurrentPattern.ReplaceAllStringFunc(string(rawBytes[:]), func(m string) string {
-		if com.StrTo(m).MustInt() > 0 {
-			return m
+// renderSha1CurrentPattern renders SHA1 strings to corresponding links that assumes in the same repository.
+func renderSha1CurrentPattern(rawBytes []byte, urlPrefix string) []byte {
+	ms := Sha1CurrentPattern.FindAllSubmatch(rawBytes, -1)
+	for _, m := range ms {
+		all := m[0]
+		if com.StrTo(all).MustInt() > 0 {
+			continue
 		}
-		return fmt.Sprintf(`<a href="%s/commit/%s"><code>%s</code></a>`, urlPrefix, m, base.ShortSha(m))
-	}))
+		rawBytes = bytes.Replace(rawBytes, all, []byte(fmt.Sprintf(
+			`<a href="%s">%s</a>`, URLJoin(urlPrefix, "commit", string(all)), base.ShortSha(string(all)))), -1)
+	}
+	return rawBytes
 }
 
 // RenderSpecialLink renders mentions, indexes and SHA1 strings to corresponding links.
@@ -311,23 +553,27 @@ func RenderSpecialLink(rawBytes []byte, urlPrefix string, metas map[string]strin
 	for _, m := range ms {
 		m = m[bytes.Index(m, []byte("@")):]
 		rawBytes = bytes.Replace(rawBytes, m,
-			[]byte(fmt.Sprintf(`<a href="%s/%s">%s</a>`, setting.AppSubURL, m[1:], m)), -1)
+			[]byte(fmt.Sprintf(`<a href="%s">%s</a>`, URLJoin(setting.AppURL, string(m[1:])), m)), -1)
 	}
 
+	rawBytes = renderShortLinks(rawBytes, urlPrefix, false)
 	rawBytes = RenderIssueIndexPattern(rawBytes, urlPrefix, metas)
 	rawBytes = RenderCrossReferenceIssueIndexPattern(rawBytes, urlPrefix, metas)
-	rawBytes = RenderSha1CurrentPattern(rawBytes, urlPrefix)
+	rawBytes = renderFullSha1Pattern(rawBytes, urlPrefix)
+	rawBytes = renderSha1CurrentPattern(rawBytes, urlPrefix)
+	rawBytes = renderFullIssuePattern(rawBytes, urlPrefix)
 	return rawBytes
 }
 
 // RenderRaw renders Markdown to HTML without handling special links.
-func RenderRaw(body []byte, urlPrefix string) []byte {
+func RenderRaw(body []byte, urlPrefix string, wikiMarkdown bool) []byte {
 	htmlFlags := 0
 	htmlFlags |= blackfriday.HTML_SKIP_STYLE
 	htmlFlags |= blackfriday.HTML_OMIT_CONTENTS
 	renderer := &Renderer{
-		Renderer:  blackfriday.HtmlRenderer(htmlFlags, "", ""),
-		urlPrefix: urlPrefix,
+		Renderer:       blackfriday.HtmlRenderer(htmlFlags, "", ""),
+		urlPrefix:      urlPrefix,
+		isWikiMarkdown: wikiMarkdown,
 	}
 
 	// set up the parser
@@ -335,9 +581,7 @@ func RenderRaw(body []byte, urlPrefix string) []byte {
 	extensions |= blackfriday.EXTENSION_NO_INTRA_EMPHASIS
 	extensions |= blackfriday.EXTENSION_TABLES
 	extensions |= blackfriday.EXTENSION_FENCED_CODE
-	extensions |= blackfriday.EXTENSION_AUTOLINK
 	extensions |= blackfriday.EXTENSION_STRIKETHROUGH
-	extensions |= blackfriday.EXTENSION_SPACE_HEADERS
 	extensions |= blackfriday.EXTENSION_NO_EMPTY_LINE_BEFORE_BLOCK
 
 	if setting.Markdown.EnableHardLineBreak {
@@ -379,10 +623,12 @@ OUTER_LOOP:
 					token = tokenizer.Token()
 
 					// Copy the token to the output verbatim
-					buf.WriteString(token.String())
+					buf.Write(renderShortLinks([]byte(token.String()), urlPrefix, true))
 
 					if token.Type == html.StartTagToken {
-						stackNum++
+						if !com.IsSliceContainsStr(noEndTags, token.Data) {
+							stackNum++
+						}
 					}
 
 					// If this is the close tag to the outer-most, we are done
@@ -425,16 +671,26 @@ OUTER_LOOP:
 	return rawHTML
 }
 
-// Render renders Markdown to HTML with special links.
-func Render(rawBytes []byte, urlPrefix string, metas map[string]string) []byte {
-	urlPrefix = strings.Replace(urlPrefix, space, spaceEncoded, -1)
-	result := RenderRaw(rawBytes, urlPrefix)
+// Render renders Markdown to HTML with all specific handling stuff.
+func render(rawBytes []byte, urlPrefix string, metas map[string]string, isWikiMarkdown bool) []byte {
+	urlPrefix = strings.Replace(urlPrefix, " ", "%20", -1)
+	result := RenderRaw(rawBytes, urlPrefix, isWikiMarkdown)
 	result = PostProcess(result, urlPrefix, metas)
 	result = Sanitizer.SanitizeBytes(result)
 	return result
 }
 
+// Render renders Markdown to HTML with all specific handling stuff.
+func Render(rawBytes []byte, urlPrefix string, metas map[string]string) []byte {
+	return render(rawBytes, urlPrefix, metas, false)
+}
+
 // RenderString renders Markdown to HTML with special links and returns string type.
 func RenderString(raw, urlPrefix string, metas map[string]string) string {
-	return string(Render([]byte(raw), urlPrefix, metas))
+	return string(render([]byte(raw), urlPrefix, metas, false))
+}
+
+// RenderWiki renders markdown wiki page to HTML and return HTML string
+func RenderWiki(rawBytes []byte, urlPrefix string, metas map[string]string) string {
+	return string(render(rawBytes, urlPrefix, metas, true))
 }
diff --git a/modules/markdown/markdown_test.go b/modules/markdown/markdown_test.go
index 88b48548eb..60dd0afde2 100644
--- a/modules/markdown/markdown_test.go
+++ b/modules/markdown/markdown_test.go
@@ -1,21 +1,20 @@
 package markdown_test
 
 import (
-	"bytes"
 	"fmt"
-	"net/url"
-	"path"
 	"strconv"
 	"testing"
 
+	"strings"
+
 	. "code.gitea.io/gitea/modules/markdown"
 	"code.gitea.io/gitea/modules/setting"
-
-	"github.com/russross/blackfriday"
 	"github.com/stretchr/testify/assert"
 )
 
-const urlPrefix = "/prefix"
+const AppURL = "http://localhost:3000/"
+const Repo = "gogits/gogs"
+const AppSubURL = AppURL + Repo + "/"
 
 var numericMetas = map[string]string{
 	"format": "https://someurl.com/{user}/{repo}/{index}",
@@ -33,16 +32,12 @@ var alphanumericMetas = map[string]string{
 
 // numericLink an HTML to a numeric-style issue
 func numericIssueLink(baseURL string, index int) string {
-	u, _ := url.Parse(baseURL)
-	u.Path = path.Join(u.Path, strconv.Itoa(index))
-	return link(u.String(), fmt.Sprintf("#%d", index))
+	return link(URLJoin(baseURL, strconv.Itoa(index)), fmt.Sprintf("#%d", index))
 }
 
 // alphanumLink an HTML link to an alphanumeric-style issue
 func alphanumIssueLink(baseURL string, name string) string {
-	u, _ := url.Parse(baseURL)
-	u.Path = path.Join(u.Path, name)
-	return link(u.String(), name)
+	return link(URLJoin(baseURL, name), name)
 }
 
 // urlContentsLink an HTML link whose contents is the target URL
@@ -57,7 +52,7 @@ func link(href, contents string) string {
 
 func testRenderIssueIndexPattern(t *testing.T, input, expected string, metas map[string]string) {
 	assert.Equal(t, expected,
-		string(RenderIssueIndexPattern([]byte(input), urlPrefix, metas)))
+		string(RenderIssueIndexPattern([]byte(input), AppSubURL, metas)))
 }
 
 func TestRenderIssueIndexPattern(t *testing.T) {
@@ -88,11 +83,14 @@ func TestRenderIssueIndexPattern(t *testing.T) {
 }
 
 func TestRenderIssueIndexPattern2(t *testing.T) {
+	setting.AppURL = AppURL
+	setting.AppSubURL = AppSubURL
+
 	// numeric: render inputs with valid mentions
 	test := func(s, expectedFmt string, indices ...int) {
 		links := make([]interface{}, len(indices))
 		for i, index := range indices {
-			links[i] = numericIssueLink(path.Join(urlPrefix, "issues"), index)
+			links[i] = numericIssueLink(URLJoin(setting.AppSubURL, "issues"), index)
 		}
 		expectedNil := fmt.Sprintf(expectedFmt, links...)
 		testRenderIssueIndexPattern(t, s, expectedNil, nil)
@@ -122,6 +120,9 @@ func TestRenderIssueIndexPattern2(t *testing.T) {
 }
 
 func TestRenderIssueIndexPattern3(t *testing.T) {
+	setting.AppURL = AppURL
+	setting.AppSubURL = AppSubURL
+
 	// alphanumeric: render inputs without valid mentions
 	test := func(s string) {
 		testRenderIssueIndexPattern(t, s, s, alphanumericMetas)
@@ -146,6 +147,9 @@ func TestRenderIssueIndexPattern3(t *testing.T) {
 }
 
 func TestRenderIssueIndexPattern4(t *testing.T) {
+	setting.AppURL = AppURL
+	setting.AppSubURL = AppSubURL
+
 	// alphanumeric: render inputs with valid mentions
 	test := func(s, expectedFmt string, names ...string) {
 		links := make([]interface{}, len(names))
@@ -161,36 +165,509 @@ func TestRenderIssueIndexPattern4(t *testing.T) {
 }
 
 func TestRenderer_AutoLink(t *testing.T) {
-	setting.AppURL = "http://localhost:3000/"
-	htmlFlags := blackfriday.HTML_SKIP_STYLE | blackfriday.HTML_OMIT_CONTENTS
-	renderer := &Renderer{
-		Renderer: blackfriday.HtmlRenderer(htmlFlags, "", ""),
-	}
+	setting.AppURL = AppURL
+	setting.AppSubURL = AppSubURL
+
+	SubURLNoProtocol := setting.AppSubURL[5:]
+
 	test := func(input, expected string) {
-		buffer := new(bytes.Buffer)
-		renderer.AutoLink(buffer, []byte(input), blackfriday.LINK_TYPE_NORMAL)
-		assert.Equal(t, expected, buffer.String())
+		buffer := RenderSpecialLink([]byte(input), setting.AppSubURL, map[string]string{})
+		assert.Equal(t, expected, string(buffer))
 	}
 
 	// render valid issue URLs
-	test("http://localhost:3000/user/repo/issues/3333",
-		numericIssueLink("http://localhost:3000/user/repo/issues/", 3333))
+	test(URLJoin(setting.AppSubURL, "issues", "3333"),
+		numericIssueLink(URLJoin(setting.AppSubURL, "issues"), 3333))
 
-	// render, but not change, invalid issue URLs
-	test("http://1111/2222/ssss-issues/3333?param=blah&blahh=333",
-		urlContentsLink("http://1111/2222/ssss-issues/3333?param=blah&amp;blahh=333"))
-	test("http://test.com/issues/33333", urlContentsLink("http://test.com/issues/33333"))
-	test("https://issues/333", urlContentsLink("https://issues/333"))
+	// render external issue URLs
+	tmp := "//1111/2222/ssss-issues/3333?param=blah&blahh=333"
+	test("http:"+tmp,
+		"<a href=\""+tmp+"\">#3333 <i class='comment icon'></i></a>")
+	test("http://test.com/issues/33333", numericIssueLink("//test.com/issues", 33333))
+	test("https://issues/333", numericIssueLink("//issues", 333))
 
 	// render valid commit URLs
-	test("http://localhost:3000/user/project/commit/d8a994ef243349f321568f9e36d5c3f444b99cae",
-		" <code><a href=\"http://localhost:3000/user/project/commit/d8a994ef243349f321568f9e36d5c3f444b99cae\">d8a994ef24</a></code>")
-	test("http://localhost:3000/user/project/commit/d8a994ef243349f321568f9e36d5c3f444b99cae#diff-2",
-		" <code><a href=\"http://localhost:3000/user/project/commit/d8a994ef243349f321568f9e36d5c3f444b99cae#diff-2\">d8a994ef24</a></code>")
+	tmp = URLJoin(SubURLNoProtocol, "commit", "d8a994ef243349f321568f9e36d5c3f444b99cae")
+	test("http://"+tmp, "<a href=\""+tmp+"\">d8a994ef24</a>")
+	tmp += "#diff-2"
+	test("http://"+tmp, "<a href=\""+tmp+"\">d8a994ef24 (diff-2)</a>")
 
 	// render other commit URLs
-	test("https://external-link.gogs.io/gogs/gogs/commit/d8a994ef243349f321568f9e36d5c3f444b99cae#diff-2",
-		urlContentsLink("https://external-link.gogs.io/gogs/gogs/commit/d8a994ef243349f321568f9e36d5c3f444b99cae#diff-2"))
-	test("https://commit/d8a994ef243349f321568f9e36d5c3f444b99cae",
-		urlContentsLink("https://commit/d8a994ef243349f321568f9e36d5c3f444b99cae"))
+	tmp = "//external-link.gogs.io/gogs/gogs/commit/d8a994ef243349f321568f9e36d5c3f444b99cae#diff-2"
+	test("https:"+tmp, "<a href=\""+tmp+"\">d8a994ef24 (diff-2)</a>")
+}
+
+func TestRender_ShortLinks(t *testing.T) {
+	setting.AppURL = AppURL
+	setting.AppSubURL = AppSubURL
+
+	test := func(input, expected string) {
+		buffer := RenderString(input, setting.AppSubURL, nil)
+		assert.Equal(t, expected, string(buffer))
+	}
+
+	var url = URLJoin(AppSubURL, "wiki", "Link")
+	var imgurl = URLJoin(AppSubURL, "wiki", "raw", "Link.jpg")
+	var favicon = "http://google.com/favicon.ico"
+
+	test("[[Link]]", `<p><a href="`+url+`" rel="nofollow">Link</a></p>
+`)
+	test("[[Link.jpg]]", `<p><a href="`+imgurl+`" rel="nofollow"><img src="`+imgurl+`" alt="Link.jpg" title="Link.jpg"/></a></p>
+`)
+	test("[["+favicon+"]]", `<p><a href="`+favicon+`" rel="nofollow"><img src="`+favicon+`" title="favicon.ico"/></a></p>
+`)
+	test("[[Name|Link]]", `<p><a href="`+url+`" rel="nofollow">Name</a></p>
+`)
+	test("[[Name|Link.jpg]]", `<p><a href="`+imgurl+`" rel="nofollow"><img src="`+imgurl+`" alt="Name" title="Name"/></a></p>
+`)
+	test("[[Name|Link.jpg|alt=AltName]]", `<p><a href="`+imgurl+`" rel="nofollow"><img src="`+imgurl+`" alt="AltName" title="AltName"/></a></p>
+`)
+	test("[[Name|Link.jpg|title=Title]]", `<p><a href="`+imgurl+`" rel="nofollow"><img src="`+imgurl+`" alt="Title" title="Title"/></a></p>
+`)
+	test("[[Name|Link.jpg|alt=AltName|title=Title]]", `<p><a href="`+imgurl+`" rel="nofollow"><img src="`+imgurl+`" alt="AltName" title="Title"/></a></p>
+`)
+	test("[[Name|Link.jpg|alt=\"AltName\"|title='Title']]", `<p><a href="`+imgurl+`" rel="nofollow"><img src="`+imgurl+`" alt="AltName" title="Title"/></a></p>
+`)
+}
+
+func TestRender_Commits(t *testing.T) {
+	setting.AppURL = AppURL
+	setting.AppSubURL = AppSubURL
+
+	test := func(input, expected string) {
+		buffer := RenderString(input, setting.AppSubURL, nil)
+		assert.Equal(t, expected, string(buffer))
+	}
+
+	var sha = "b6dd6210eaebc915fd5be5579c58cce4da2e2579"
+	var commit = URLJoin(AppSubURL, "commit", sha)
+	var subtree = URLJoin(commit, "src")
+	var tree = strings.Replace(subtree, "/commit/", "/tree/", -1)
+	var src = strings.Replace(subtree, "/commit/", "/src/", -1)
+
+	test(sha, `<p><a href="`+commit+`" rel="nofollow">b6dd6210ea</a></p>
+`)
+	test(commit, `<p><a href="`+commit[5:]+`" rel="nofollow">b6dd6210ea</a></p>
+`)
+	test(tree, `<p><a href="`+src[5:]+`" rel="nofollow">b6dd6210ea/src</a></p>
+`)
+}
+
+func TestRegExp_MentionPattern(t *testing.T) {
+	trueTestCases := []string{
+		"@Unknwon",
+		"@ANT_123",
+		"@xxx-DiN0-z-A..uru..s-xxx",
+		"   @lol   ",
+		" @Te/st",
+	}
+	falseTestCases := []string{
+		"@ 0",
+		"@ ",
+		"@",
+		"",
+		"ABC",
+	}
+
+	for _, testCase := range trueTestCases {
+		res := MentionPattern.MatchString(testCase)
+		if !res {
+			println()
+			println(testCase)
+		}
+		assert.True(t, res)
+	}
+	for _, testCase := range falseTestCases {
+		res := MentionPattern.MatchString(testCase)
+		if res {
+			println()
+			println(testCase)
+		}
+		assert.False(t, res)
+	}
+}
+
+func TestRegExp_IssueNumericPattern(t *testing.T) {
+	trueTestCases := []string{
+		"#1234",
+		"#0",
+		"#1234567890987654321",
+	}
+	falseTestCases := []string{
+		"# 1234",
+		"# 0",
+		"# ",
+		"#",
+		"#ABC",
+		"#1A2B",
+		"",
+		"ABC",
+	}
+
+	for _, testCase := range trueTestCases {
+		assert.True(t, IssueNumericPattern.MatchString(testCase))
+	}
+	for _, testCase := range falseTestCases {
+		assert.False(t, IssueNumericPattern.MatchString(testCase))
+	}
+}
+
+func TestRegExp_IssueAlphanumericPattern(t *testing.T) {
+	trueTestCases := []string{
+		"ABC-1234",
+		"A-1",
+		"RC-80",
+		"ABCDEFGHIJ-1234567890987654321234567890",
+	}
+	falseTestCases := []string{
+		"RC-08",
+		"PR-0",
+		"ABCDEFGHIJK-1",
+		"PR_1",
+		"",
+		"#ABC",
+		"",
+		"ABC",
+		"GG-",
+		"rm-1",
+	}
+
+	for _, testCase := range trueTestCases {
+		assert.True(t, IssueAlphanumericPattern.MatchString(testCase))
+	}
+	for _, testCase := range falseTestCases {
+		assert.False(t, IssueAlphanumericPattern.MatchString(testCase))
+	}
+}
+
+func TestRegExp_Sha1CurrentPattern(t *testing.T) {
+	trueTestCases := []string{
+		"d8a994ef243349f321568f9e36d5c3f444b99cae",
+		"abcdefabcdefabcdefabcdefabcdefabcdefabcd",
+	}
+	falseTestCases := []string{
+		"test",
+		"abcdefg",
+		"abcdefghijklmnopqrstuvwxyzabcdefghijklmn",
+		"abcdefghijklmnopqrstuvwxyzabcdefghijklmO",
+	}
+
+	for _, testCase := range trueTestCases {
+		assert.True(t, Sha1CurrentPattern.MatchString(testCase))
+	}
+	for _, testCase := range falseTestCases {
+		assert.False(t, Sha1CurrentPattern.MatchString(testCase))
+	}
+}
+
+func TestRegExp_ShortLinkPattern(t *testing.T) {
+	trueTestCases := []string{
+		"[[stuff]]",
+		"[[]]",
+		"[[stuff|title=Difficult name with spaces*!]]",
+	}
+	falseTestCases := []string{
+		"test",
+		"abcdefg",
+		"[[]",
+		"[[",
+		"[]",
+		"]]",
+		"abcdefghijklmnopqrstuvwxyz",
+	}
+
+	for _, testCase := range trueTestCases {
+		assert.True(t, ShortLinkPattern.MatchString(testCase))
+	}
+	for _, testCase := range falseTestCases {
+		assert.False(t, ShortLinkPattern.MatchString(testCase))
+	}
+}
+
+func TestRegExp_AnySHA1Pattern(t *testing.T) {
+	testCases := map[string][]string{
+		"https://github.com/jquery/jquery/blob/a644101ed04d0beacea864ce805e0c4f86ba1cd1/test/unit/event.js#L2703": []string{
+			"github.com",
+			"jquery",
+			"jquery",
+			"blob",
+			"a644101ed04d0beacea864ce805e0c4f86ba1cd1",
+			"test/unit/event.js",
+			"L2703",
+		},
+		"https://github.com/jquery/jquery/blob/a644101ed04d0beacea864ce805e0c4f86ba1cd1/test/unit/event.js": []string{
+			"github.com",
+			"jquery",
+			"jquery",
+			"blob",
+			"a644101ed04d0beacea864ce805e0c4f86ba1cd1",
+			"test/unit/event.js",
+			"",
+		},
+		"https://github.com/jquery/jquery/commit/0705be475092aede1eddae01319ec931fb9c65fc": []string{
+			"github.com",
+			"jquery",
+			"jquery",
+			"commit",
+			"0705be475092aede1eddae01319ec931fb9c65fc",
+			"",
+			"",
+		},
+		"https://github.com/jquery/jquery/tree/0705be475092aede1eddae01319ec931fb9c65fc/src": []string{
+			"github.com",
+			"jquery",
+			"jquery",
+			"tree",
+			"0705be475092aede1eddae01319ec931fb9c65fc",
+			"src",
+			"",
+		},
+		"https://try.gogs.io/gogs/gogs/commit/d8a994ef243349f321568f9e36d5c3f444b99cae#diff-2": []string{
+			"try.gogs.io",
+			"gogs",
+			"gogs",
+			"commit",
+			"d8a994ef243349f321568f9e36d5c3f444b99cae",
+			"",
+			"diff-2",
+		},
+	}
+
+	for k, v := range testCases {
+		assert.Equal(t, AnySHA1Pattern.FindStringSubmatch(k)[1:], v)
+	}
+}
+
+func TestRegExp_IssueFullPattern(t *testing.T) {
+	testCases := map[string][]string{
+		"https://github.com/gogits/gogs/pull/3244": []string{
+			"github.com/gogits/gogs/pull/",
+			"3244",
+			"",
+			"",
+		},
+		"https://github.com/gogits/gogs/issues/3247#issuecomment-231517079": []string{
+			"github.com/gogits/gogs/issues/",
+			"3247",
+			"#issuecomment-231517079",
+			"",
+		},
+		"https://try.gogs.io/gogs/gogs/issues/4#issue-685": []string{
+			"try.gogs.io/gogs/gogs/issues/",
+			"4",
+			"#issue-685",
+			"",
+		},
+		"https://youtrack.jetbrains.com/issue/JT-36485": []string{
+			"youtrack.jetbrains.com/issue/",
+			"JT-36485",
+			"",
+			"",
+		},
+		"https://youtrack.jetbrains.com/issue/JT-36485#comment=27-1508676": []string{
+			"youtrack.jetbrains.com/issue/",
+			"JT-36485",
+			"#comment=27-1508676",
+			"",
+		},
+	}
+
+	for k, v := range testCases {
+		assert.Equal(t, IssueFullPattern.FindStringSubmatch(k)[1:], v)
+	}
+}
+
+func TestMisc_IsMarkdownFile(t *testing.T) {
+	setting.Markdown.FileExtensions = []string{".md", ".markdown", ".mdown", ".mkd"}
+	trueTestCases := []string{
+		"test.md",
+		"wow.MARKDOWN",
+		"LOL.mDoWn",
+	}
+	falseTestCases := []string{
+		"test",
+		"abcdefg",
+		"abcdefghijklmnopqrstuvwxyz",
+		"test.md.test",
+	}
+
+	for _, testCase := range trueTestCases {
+		assert.True(t, IsMarkdownFile(testCase))
+	}
+	for _, testCase := range falseTestCases {
+		assert.False(t, IsMarkdownFile(testCase))
+	}
+}
+
+func TestMisc_IsReadmeFile(t *testing.T) {
+	trueTestCases := []string{
+		"readme",
+		"README",
+		"readME.mdown",
+		"README.md",
+	}
+	falseTestCases := []string{
+		"test.md",
+		"wow.MARKDOWN",
+		"LOL.mDoWn",
+		"test",
+		"abcdefg",
+		"abcdefghijklmnopqrstuvwxyz",
+		"test.md.test",
+	}
+
+	for _, testCase := range trueTestCases {
+		assert.True(t, IsReadmeFile(testCase))
+	}
+	for _, testCase := range falseTestCases {
+		assert.False(t, IsReadmeFile(testCase))
+	}
+}
+
+func TestMisc_IsSameDomain(t *testing.T) {
+	setting.AppURL = AppURL
+	setting.AppSubURL = AppSubURL
+
+	var sha = "b6dd6210eaebc915fd5be5579c58cce4da2e2579"
+	var commit = URLJoin(AppSubURL, "commit", sha)
+
+	assert.True(t, IsSameDomain(commit))
+	assert.False(t, IsSameDomain("http://google.com/ncr"))
+	assert.False(t, IsSameDomain("favicon.ico"))
+}
+
+// Test cases without ambiguous links
+var sameCases = []string{
+	// dear imgui wiki markdown extract: special wiki syntax
+	`Wiki! Enjoy :)
+- [[Links, Language bindings, Engine bindings|Links]]
+- [[Tips]]
+
+Ideas and codes
+
+- Bezier widget (by @r-lyeh) https://github.com/ocornut/imgui/issues/786
+- Node graph editors https://github.com/ocornut/imgui/issues/306
+- [[Memory Editor|memory_editor_example]]
+- [[Plot var helper|plot_var_example]]`,
+	// rendered
+	`<p>Wiki! Enjoy :)</p>
+
+<ul>
+<li><a href="` + AppSubURL + `wiki/Links" rel="nofollow">Links, Language bindings, Engine bindings</a></li>
+<li><a href="` + AppSubURL + `wiki/Tips" rel="nofollow">Tips</a></li>
+</ul>
+
+<p>Ideas and codes</p>
+
+<ul>
+<li>Bezier widget (by <a href="` + AppURL + `r-lyeh" rel="nofollow">@r-lyeh</a>)<a href="` + AppSubURL + `issues/786" rel="nofollow">#786</a></li>
+<li>Node graph editors<a href="` + AppSubURL + `issues/306" rel="nofollow">#306</a></li>
+<li><a href="` + AppSubURL + `wiki/memory_editor_example" rel="nofollow">Memory Editor</a></li>
+<li><a href="` + AppSubURL + `wiki/plot_var_example" rel="nofollow">Plot var helper</a></li>
+</ul>
+`,
+	// wine-staging wiki home extract: tables, special wiki syntax, images
+	`## What is Wine Staging?
+**Wine Staging** on website [wine-staging.com](http://wine-staging.com).
+
+## Quick Links
+Here are some links to the most important topics. You can find the full list of pages at the sidebar.
+
+| [[images/icon-install.png]]    | [[Installation]]                                         |
+|--------------------------------|----------------------------------------------------------|
+| [[images/icon-usage.png]]      | [[Usage]]                                                |
+| [[images/icon-config.png]]     | [[Configuration]]                                        |
+| [[images/icon-bug.png]]        | [Bugs](http://bugs.wine-staging.com)                     |
+`,
+	// rendered
+	`<h2>What is Wine Staging?</h2>
+
+<p><strong>Wine Staging</strong> on website <a href="http://wine-staging.com" rel="nofollow">wine-staging.com</a>.</p>
+
+<h2>Quick Links</h2>
+
+<p>Here are some links to the most important topics. You can find the full list of pages at the sidebar.</p>
+
+<table>
+<thead>
+<tr>
+<th><a href="` + AppSubURL + `wiki/raw/images%2Ficon-install.png" rel="nofollow"><img src="` + AppSubURL + `wiki/raw/images%2Ficon-install.png" alt="images/icon-install.png" title="icon-install.png"/></a></th>
+<th><a href="` + AppSubURL + `wiki/Installation" rel="nofollow">Installation</a></th>
+</tr>
+</thead>
+
+<tbody>
+<tr>
+<td><a href="` + AppSubURL + `wiki/raw/images%2Ficon-usage.png" rel="nofollow"><img src="` + AppSubURL + `wiki/raw/images%2Ficon-usage.png" alt="images/icon-usage.png" title="icon-usage.png"/></a></td>
+<td><a href="` + AppSubURL + `wiki/Usage" rel="nofollow">Usage</a></td>
+</tr>
+
+<tr>
+<td><a href="` + AppSubURL + `wiki/raw/images%2Ficon-config.png" rel="nofollow"><img src="` + AppSubURL + `wiki/raw/images%2Ficon-config.png" alt="images/icon-config.png" title="icon-config.png"/></a></td>
+<td><a href="` + AppSubURL + `wiki/Configuration" rel="nofollow">Configuration</a></td>
+</tr>
+
+<tr>
+<td><a href="` + AppSubURL + `wiki/raw/images%2Ficon-bug.png" rel="nofollow"><img src="` + AppSubURL + `wiki/raw/images%2Ficon-bug.png" alt="images/icon-bug.png" title="icon-bug.png"/></a></td>
+<td><a href="http://bugs.wine-staging.com" rel="nofollow">Bugs</a></td>
+</tr>
+</tbody>
+</table>
+`,
+	// libgdx wiki page: inline images with special syntax
+	`[Excelsior JET](http://www.excelsiorjet.com/) allows you to create native executables for Windows, Linux and Mac OS X.
+
+1. [Package your libGDX application](https://github.com/libgdx/libgdx/wiki/Gradle-on-the-Commandline#packaging-for-the-desktop)
+[[images/1.png]]
+2. Perform a test run by hitting the Run! button.
+[[images/2.png]]`,
+	// rendered
+	`<p><a href="http://www.excelsiorjet.com/" rel="nofollow">Excelsior JET</a> allows you to create native executables for Windows, Linux and Mac OS X.</p>
+
+<ol>
+<li><a href="https://github.com/libgdx/libgdx/wiki/Gradle-on-the-Commandline#packaging-for-the-desktop" rel="nofollow">Package your libGDX application</a>
+<a href="` + AppSubURL + `wiki/raw/images%2F1.png" rel="nofollow"><img src="` + AppSubURL + `wiki/raw/images%2F1.png" alt="images/1.png" title="1.png"/></a></li>
+<li>Perform a test run by hitting the Run! button.
+<a href="` + AppSubURL + `wiki/raw/images%2F2.png" rel="nofollow"><img src="` + AppSubURL + `wiki/raw/images%2F2.png" alt="images/2.png" title="2.png"/></a></li>
+</ol>
+`,
+}
+
+func TestTotal_RenderString(t *testing.T) {
+	for i := 0; i < len(sameCases); i += 2 {
+		line := RenderString(sameCases[i], AppSubURL, map[string]string{})
+		assert.Equal(t, sameCases[i+1], line)
+	}
+
+	testCases := []string{}
+
+	for i := 0; i < len(testCases); i += 2 {
+		line := RenderString(testCases[i], AppSubURL, map[string]string{})
+		assert.Equal(t, testCases[i+1], line)
+	}
+}
+
+func TestTotal_RenderWiki(t *testing.T) {
+	for i := 0; i < len(sameCases); i += 2 {
+		line := RenderWiki([]byte(sameCases[i]), AppSubURL, map[string]string{})
+		assert.Equal(t, sameCases[i+1], line)
+	}
+
+	testCases := []string{
+		// Guard wiki sidebar: special syntax
+		`[[Guardfile-DSL / Configuring-Guard|Guardfile-DSL---Configuring-Guard]]`,
+		// rendered
+		`<p><a href="` + AppSubURL + `wiki/Guardfile-DSL---Configuring-Guard" rel="nofollow">Guardfile-DSL / Configuring-Guard</a></p>
+`,
+		// special syntax
+		`[[Name|Link]]`,
+		// rendered
+		`<p><a href="` + AppSubURL + `wiki/Link" rel="nofollow">Name</a></p>
+`,
+	}
+
+	for i := 0; i < len(testCases); i += 2 {
+		line := RenderWiki([]byte(testCases[i]), AppSubURL, map[string]string{})
+		assert.Equal(t, testCases[i+1], line)
+	}
 }