Render the Code view on the server (minus syntax highlighting) (#2942)

* render code view server side

* remove debug print

* fix multiline selection bug

* change string concatenation to bytes.Buffer for efficiency

* Fix newlines added by previous for hljs

* fix selection highlighting

* make css changes in .less

5 files changed, 24 insertions, 20 deletions

diff --git a/public/css/gogs.css b/public/css/gogs.css
index ae58c7c54e..c39c52ca22 100644
--- a/public/css/gogs.css
+++ b/public/css/gogs.css
@@ -1316,6 +1316,8 @@ footer .ui.language .menu {
 .repository.file.list #file-content .code-view .lines-num .hljs li,
 .repository.file.list #file-content .code-view .lines-code .hljs li {
   padding-left: 5px;
+  display: inline-block;
+  width: 100%;
 }
 .repository.file.list #file-content .code-view .lines-num pre li.active,
 .repository.file.list #file-content .code-view .lines-code pre li.active,
diff --git a/public/js/gogs.js b/public/js/gogs.js
index 226bb6bae5..c6a1b6b624 100644
--- a/public/js/gogs.js
+++ b/public/js/gogs.js
@@ -1088,7 +1088,7 @@ $(window).load(function () {
                     b = c;
                 }
                 var classes = [];
-                for (i = a; i <= b; i++) {
+                for (var i = a; i <= b; i++) {
                     classes.push('.L' + i);
                 }
                 $list.filter(classes.join(',')).addClass('active');
@@ -1102,22 +1102,6 @@ $(window).load(function () {
 
     // Code view.
     if ($('.code-view .linenums').length > 0) {
-        var $block = $('.code-view .linenums');
-        var lines = $block.html().split("\n");
-        $block.html('');
-
-        var $num_list = $('.code-view .lines-num');
-
-        // Building blocks.
-        var $toappendblock = [];
-        var $toappendnum_list = [];
-        for (var i = 0; i < lines.length; i++) {
-            $toappendblock.push('<li class="L' + (i + 1) + '" rel="L' + (i + 1) + '">' + lines[i] + '</li>');
-            $toappendnum_list.push('<span id="L' + (i + 1) + '">' + (i + 1) + '</span>');
-        }
-        $block.append($toappendblock.join(''));
-        $num_list.append($toappendnum_list.join(''));
-
         $(document).on('click', '.lines-num span', function (e) {
             var $select = $(this);
             var $list = $select.parent().siblings('.lines-code').find('ol.linenums > li');
diff --git a/public/less/_repository.less b/public/less/_repository.less
index 474b8ade6d..cb1cc121ce 100644
--- a/public/less/_repository.less
+++ b/public/less/_repository.less
@@ -251,6 +251,8 @@
 						padding: 0 !important;
 						li {
 							padding-left: 5px;
+							display: inline-block;
+							width: 100%;
 							&.active {
 								background: #ffffdd;
 							}
diff --git a/routers/repo/view.go b/routers/repo/view.go
index 7bcdc1293c..c13f57f426 100644
--- a/routers/repo/view.go
+++ b/routers/repo/view.go
@@ -5,11 +5,14 @@
 package repo
 
 import (
+	"fmt"
 	"bytes"
 	"io/ioutil"
 	"path"
 	"strings"
 
+	htmltemplate "html/template"
+
 	"github.com/Unknwon/paginater"
 
 	"github.com/gogits/git-module"
@@ -116,14 +119,27 @@ func Home(ctx *context.Context) {
 					if readmeExist {
 						ctx.Data["FileContent"] = string(markdown.Render(buf, path.Dir(treeLink), ctx.Repo.Repository.ComposeMetas()))
 					} else {
+						filecontent := ""
 						if err, content := template.ToUtf8WithErr(buf); err != nil {
 							if err != nil {
 								log.Error(4, "Convert content encoding: %s", err)
 							}
-							ctx.Data["FileContent"] = string(buf)
+							filecontent = string(buf)
 						} else {
-							ctx.Data["FileContent"] = content
+							filecontent = content
+						}
+						var output bytes.Buffer
+						lines := strings.Split(filecontent, "\n")
+						for index, line := range lines {
+							output.WriteString(fmt.Sprintf(`<li class="L%d" rel="L%d">%s</li>`, index+1, index+1, htmltemplate.HTMLEscapeString(line)) + "\n")
+						}
+						ctx.Data["FileContent"] = htmltemplate.HTML(output.String())
+
+						output.Reset()
+						for i := 0; i < len(lines); i++ {
+							output.WriteString(fmt.Sprintf(`<span id="L%d">%d</span>`, i+1, i+1))
 						}
+						ctx.Data["LineNums"] = htmltemplate.HTML(output.String())
 					}
 				}
 			}
diff --git a/templates/repo/view_file.tmpl b/templates/repo/view_file.tmpl
index cd0caf10f9..0f42df4925 100644
--- a/templates/repo/view_file.tmpl
+++ b/templates/repo/view_file.tmpl
@@ -44,7 +44,7 @@
 						{{if .IsFileTooLarge}}
 							<td><strong>{{.i18n.Tr "repo.file_too_large"}}</strong></td>
 						{{else}}
-							<td class="lines-num"></td>
+							<td class="lines-num">{{.LineNums}}</td>
 							<td class="lines-code"><pre><code class="{{.HighlightClass}}"><ol class="linenums">{{.FileContent}}</ol></code></pre></td>
 						{{end}}
 						</tr>