On showing diff/file, use the tab_width specified on .editorconfig, if any (#3241)

Closes #3182

9 files changed, 137 insertions, 2 deletions

diff --git a/modules/context/repo.go b/modules/context/repo.go
index af18881486..2f6a5de7a1 100644
--- a/modules/context/repo.go
+++ b/modules/context/repo.go
@@ -6,10 +6,12 @@ package context
 
 import (
 	"fmt"
+	"io/ioutil"
 	"path"
 	"strings"
 
 	"github.com/Unknwon/com"
+	"gopkg.in/editorconfig/editorconfig-core-go.v1"
 	"gopkg.in/macaron.v1"
 
 	"github.com/gogits/git-module"
@@ -69,6 +71,28 @@ func (r *Repository) HasAccess() bool {
 	return r.AccessMode >= models.ACCESS_MODE_READ
 }
 
+// GetEditorconfig returns the .editorconfig definition if found in the
+// HEAD of the default repo branch.
+func (r *Repository) GetEditorconfig() (*editorconfig.Editorconfig, error) {
+	commit, err := r.GitRepo.GetBranchCommit(r.Repository.DefaultBranch)
+	if err != nil {
+		return nil, err
+	}
+	treeEntry, err := commit.GetTreeEntryByPath(".editorconfig")
+	if err != nil {
+		return nil, err
+	}
+	reader, err := treeEntry.Blob().Data()
+	if err != nil {
+		return nil, err
+	}
+	data, err := ioutil.ReadAll(reader)
+	if err != nil {
+		return nil, err
+	}
+	return editorconfig.ParseBytes(data)
+}
+
 func RetrieveBaseRepo(ctx *Context, repo *models.Repository) {
 	// Non-fork repository will not return error in this method.
 	if err := repo.GetBaseRepo(); err != nil {
diff --git a/modules/template/template.go b/modules/template/template.go
index 6e9b15b9be..1b5e0a11ad 100644
--- a/modules/template/template.go
+++ b/modules/template/template.go
@@ -17,6 +17,7 @@ import (
 
 	"golang.org/x/net/html/charset"
 	"golang.org/x/text/transform"
+	"gopkg.in/editorconfig/editorconfig-core-go.v1"
 
 	"github.com/gogits/gogs/models"
 	"github.com/gogits/gogs/modules/base"
@@ -109,6 +110,15 @@ func NewFuncMap() []template.FuncMap {
 			mimeType := mime.TypeByExtension(filepath.Ext(filename))
 			return strings.HasPrefix(mimeType, "image/")
 		},
+		"TabSizeClass": func(ec *editorconfig.Editorconfig, filename string) string {
+			if ec != nil {
+				def := ec.GetDefinitionForFilename(filename)
+				if def.TabWidth > 0 {
+					return fmt.Sprintf("tab-size-%d", def.TabWidth)
+				}
+			}
+			return "tab-size-8"
+		},
 	}}
 }
 
diff --git a/public/css/gogs.css b/public/css/gogs.css
index c39c52ca22..b40ed0855d 100644
--- a/public/css/gogs.css
+++ b/public/css/gogs.css
@@ -2312,6 +2312,70 @@ footer .ui.language .menu {
 #delete-repo-modal .ui.message {
   width: 100%!important;
 }
+.tab-size-1 {
+  tab-size: 1 !important;
+  -moz-tab-size: 1 !important;
+}
+.tab-size-2 {
+  tab-size: 2 !important;
+  -moz-tab-size: 2 !important;
+}
+.tab-size-3 {
+  tab-size: 3 !important;
+  -moz-tab-size: 3 !important;
+}
+.tab-size-4 {
+  tab-size: 4 !important;
+  -moz-tab-size: 4 !important;
+}
+.tab-size-5 {
+  tab-size: 5 !important;
+  -moz-tab-size: 5 !important;
+}
+.tab-size-6 {
+  tab-size: 6 !important;
+  -moz-tab-size: 6 !important;
+}
+.tab-size-7 {
+  tab-size: 7 !important;
+  -moz-tab-size: 7 !important;
+}
+.tab-size-8 {
+  tab-size: 8 !important;
+  -moz-tab-size: 8 !important;
+}
+.tab-size-9 {
+  tab-size: 9 !important;
+  -moz-tab-size: 9 !important;
+}
+.tab-size-10 {
+  tab-size: 10 !important;
+  -moz-tab-size: 10 !important;
+}
+.tab-size-11 {
+  tab-size: 11 !important;
+  -moz-tab-size: 11 !important;
+}
+.tab-size-12 {
+  tab-size: 12 !important;
+  -moz-tab-size: 12 !important;
+}
+.tab-size-13 {
+  tab-size: 13 !important;
+  -moz-tab-size: 13 !important;
+}
+.tab-size-14 {
+  tab-size: 14 !important;
+  -moz-tab-size: 14 !important;
+}
+.tab-size-15 {
+  tab-size: 15 !important;
+  -moz-tab-size: 15 !important;
+}
+.tab-size-16 {
+  tab-size: 16 !important;
+  -moz-tab-size: 16 !important;
+}
 .organization {
   padding-top: 15px;
   padding-bottom: 80px;
diff --git a/public/less/_repository.less b/public/less/_repository.less
index 0fdc23df24..0eea2d778a 100644
--- a/public/less/_repository.less
+++ b/public/less/_repository.less
@@ -1360,3 +1360,13 @@
 		width: 100%!important;
 	}
 }
+
+// generate .tab-size-{i} from 1 to 16
+.generate-tab-size(16);
+.generate-tab-size(@n, @i: 1) when (@i =< @n) {
+	.tab-size-@{i} {
+		tab-size: @i !important;
+		-moz-tab-size: @i !important;
+	}
+	.generate-tab-size(@n, (@i + 1));
+}
diff --git a/routers/repo/commit.go b/routers/repo/commit.go
index 4eb37e6bdb..c102ceae41 100644
--- a/routers/repo/commit.go
+++ b/routers/repo/commit.go
@@ -174,6 +174,13 @@ func Diff(ctx *context.Context) {
 		}
 	}
 
+	ec, err := ctx.Repo.GetEditorconfig()
+	if err != nil && !git.IsErrNotExist(err) {
+		ctx.Handle(500, "ErrGettingEditorconfig", err)
+		return
+	}
+	ctx.Data["Editorconfig"] = ec
+
 	ctx.Data["CommitID"] = commitID
 	ctx.Data["IsSplitStyle"] = ctx.Query("style") == "split"
 	ctx.Data["Username"] = userName
diff --git a/routers/repo/pull.go b/routers/repo/pull.go
index 8fb7ae1831..77ee4bd348 100644
--- a/routers/repo/pull.go
+++ b/routers/repo/pull.go
@@ -371,6 +371,13 @@ func ViewPullFiles(ctx *context.Context) {
 		return
 	}
 
+	ec, err := ctx.Repo.GetEditorconfig()
+	if err != nil && !git.IsErrNotExist(err) {
+		ctx.Handle(500, "ErrGettingEditorconfig", err)
+		return
+	}
+	ctx.Data["Editorconfig"] = ec
+
 	headTarget := path.Join(pull.HeadUserName, pull.HeadRepo.Name)
 	ctx.Data["IsSplitStyle"] = ctx.Query("style") == "split"
 	ctx.Data["Username"] = pull.HeadUserName
@@ -623,6 +630,13 @@ func CompareAndPullRequest(ctx *context.Context) {
 		}
 	}
 
+	ec, err := ctx.Repo.GetEditorconfig()
+	if err != nil && !git.IsErrNotExist(err) {
+		ctx.Handle(500, "ErrGettingEditorconfig", err)
+		return
+	}
+	ctx.Data["Editorconfig"] = ec
+
 	ctx.HTML(200, COMPARE_PULL)
 }
 
diff --git a/routers/repo/view.go b/routers/repo/view.go
index 9c495b701c..e685597a55 100644
--- a/routers/repo/view.go
+++ b/routers/repo/view.go
@@ -225,6 +225,12 @@ func Home(ctx *context.Context) {
 	ctx.Data["Username"] = userName
 	ctx.Data["Reponame"] = repoName
 
+	ec, err := ctx.Repo.GetEditorconfig()
+	if err != nil && !git.IsErrNotExist(err) {
+		ctx.Handle(500, "ErrGettingEditorconfig", err)
+		return
+	}
+	ctx.Data["Editorconfig"] = ec
 	var treenames []string
 	paths := make([]string, 0)
 
diff --git a/templates/repo/diff_box.tmpl b/templates/repo/diff_box.tmpl
index 76a414d23e..fefca9b60d 100644
--- a/templates/repo/diff_box.tmpl
+++ b/templates/repo/diff_box.tmpl
@@ -53,7 +53,7 @@
 			</div>
 		{{else}}
 			{{$highlightClass := $file.GetHighlightClass}}
-			<div class="diff-file-box diff-box file-content" id="diff-{{.Index}}">
+			<div class="diff-file-box diff-box file-content {{TabSizeClass $.Editorconfig $file.Name}}" id="diff-{{.Index}}">
 				<h4 class="ui top attached normal header">
 					<div class="diff-counter count ui left">
 						{{if $file.IsBin}}
diff --git a/templates/repo/view_file.tmpl b/templates/repo/view_file.tmpl
index 0f42df4925..76175334d2 100644
--- a/templates/repo/view_file.tmpl
+++ b/templates/repo/view_file.tmpl
@@ -1,4 +1,4 @@
-<div id="file-content">
+<div id="file-content" class="{{TabSizeClass .Editorconfig .FileName}}">
 	<h4 class="ui top attached header" id="{{if .ReadmeExist}}repo-readme{{else}}repo-read-file{{end}}">
 		{{if .ReadmeExist}}
 			<i class="book icon ui left"></i>