Merge branch 'fix-dots-in-wiki-title' into 'master'

Fix dots in Wiki slug causing errors

### What does this MR do?

When a user enters in dots into the Wiki slug, an error occurs:

```
NoMethodError (undefined method `escaped_url_path' for nil:NilClass):
  app/models/wiki_page.rb:172:in `set_attributes'
  app/models/wiki_page.rb:191:in `save'
  app/models/wiki_page.rb:155:in `update'
  app/controllers/projects/wikis_controller.rb:49:in `update'
```

This MR fixes this problem.

### Are there points in the code the reviewer needs to double check?

See the problem below.

### Why was this MR needed?

The issue is that the `save` method gets called differently:

```ruby
def create(attr = {})
....
    save :create_page, title, content, format, message
```

or

```ruby
def update(new_content = "", format = :markdown, message = nil)
...
    save :update_page, @page, content, format, message
```

In the create case, title is the slug entered in by the user (e.g. `path/how-to-write-wiki-pages`).

In the update case, originally `@page.page` included the format extension (e.g.`path/how-to-write-wiki-pages.Markdown`). The method `page_title_and_dir` was trying to handle both cases and not doing the right thing. For example, calling `page_title_and_dir('test-1.2.3')` would result in:

```
path_title = test-1.2
path_dir = 3
```

### What are the relevant issue numbers / [Feature requests](http://feedback.gitlab.com/)?

Issues #1263, #431

This replaces !156

See merge request !419

CHANGELOG

@@ -2,6 +2,7 @@ Please view this file on the master branch, on stable branches it's out of date.
 
 v 7.10.0 (unreleased)
   - Fix "Import projects from" button to show the correct instructions (Stan Hu)
+  - Fix dots in Wiki slugs causing errors (Stan Hu)
   - Update poltergeist to version 1.6.0 to support PhantomJS 2.0 (Zeger-Jan van de Weg)
   - Fix cross references when usernames, milestones, or project names contain underscores (Stan Hu)
   - enable line wrapping per default and remove the checkbox to toggle it (Hannes Rosenögger)

app/models/project_wiki.rb

@@ -104,7 +104,7 @@ class ProjectWiki
   def page_title_and_dir(title)
     title_array =  title.split("/")
     title = title_array.pop
-    [title.gsub(/\.[^.]*$/, ""), title_array.join("/")]
+    [title, title_array.join("/")]
   end
 
   def search_files(query)

app/models/wiki_page.rb

@@ -179,7 +179,8 @@ class WikiPage
     if valid? && project_wiki.send(method, *args)
 
       page_details = if method == :update_page
-                       @page.path
+                       # Use url_path instead of path to omit format extension
+                       @page.url_path
                      else
                        title
                      end

spec/models/wiki_page_spec.rb

@@ -78,6 +78,47 @@ describe WikiPage do
     end
   end
 
+  describe "dot in the title" do
+    let(:title) { 'Index v1.2.3' }
+
+    before do
+      @wiki_attr = {title: title, content: "Home Page", format: "markdown"}
+    end
+
+    describe "#create" do
+      after do
+        destroy_page(title)
+      end
+
+      context "with valid attributes" do
+        it "saves the wiki page" do
+          subject.create(@wiki_attr)
+          expect(wiki.find_page(title)).not_to be_nil
+        end
+
+        it "returns true" do
+          expect(subject.create(@wiki_attr)).to eq(true)
+        end
+      end
+    end
+
+    describe "#update" do
+      before do
+        create_page(title, "content")
+        @page = wiki.find_page(title)
+      end
+
+      it "updates the content of the page" do
+        @page.update("new content")
+        @page = wiki.find_page(title)
+      end
+
+      it "returns true" do
+        expect(@page.update("more content")).to be_truthy
+      end
+    end
+  end
+
   describe "#update" do
     before do
       create_page("Update", "content")