Split namespace check out of project check

For group wiki which only need namespace check.

lib/gitlab/git_access.rb

@@ -24,6 +24,7 @@ module Gitlab
       deploy_key_upload: 'This deploy key does not have write access to this project.',
       no_repo: 'A repository for this project does not exist yet.',
       project_not_found: 'The project you were looking for could not be found.',
+      namespace_not_found: 'The namespace you were looking for could not be found.',
       command_not_allowed: "The command you're trying to execute is not allowed.",
       upload_pack_disabled_over_http: 'Pulling over HTTP is not allowed.',
       receive_pack_disabled_over_http: 'Pushing over HTTP is not allowed.',
@@ -73,6 +74,7 @@ module Gitlab
       return custom_action if custom_action
 
       check_db_accessibility!(cmd)
+      check_namespace!
       check_project!(changes, cmd)
       check_repository_existence!
 
@@ -111,7 +113,6 @@ module Gitlab
     private
 
     def check_project!(changes, cmd)
-      check_namespace!
       ensure_project_on_push!(cmd, changes)
       check_project_accessibility!
       add_project_moved_message!
@@ -156,7 +157,7 @@ module Gitlab
     def check_namespace!
       return if namespace_path.present?
 
-      raise NotFoundError, ERROR_MESSAGES[:project_not_found]
+      raise NotFoundError, ERROR_MESSAGES[:namespace_not_found]
     end
 
     def check_active_user!

lib/gitlab/git_access_snippet.rb

@@ -39,11 +39,17 @@ module Gitlab
 
     private
 
+    override :check_namespace!
+    def check_namespace!
+      return unless snippet.is_a?(ProjectSnippet)
+
+      super
+    end
+
     override :check_project!
     def check_project!(cmd, changes)
       return unless snippet.is_a?(ProjectSnippet)
 
-      check_namespace!
       check_project_accessibility!
       add_project_moved_message!
     end

spec/lib/gitlab/git_access_spec.rb

@@ -10,7 +10,7 @@ describe Gitlab::GitAccess do
 
   let(:actor) { user }
   let(:project) { create(:project, :repository) }
-  let(:project_path) { project.path }
+  let(:project_path) { project&.path }
   let(:namespace_path) { project&.namespace&.path }
   let(:protocol) { 'ssh' }
   let(:authentication_abilities) { %i[read_project download_code push_code] }
@@ -89,13 +89,14 @@ describe Gitlab::GitAccess do
       end
     end
 
-    context 'when namespace does not exist' do
+    context 'when namespace and project are nil' do
+      let(:project) { nil }
       let(:namespace_path) { nil }
 
       it 'does not allow push and pull access' do
         aggregate_failures do
-          expect { push_access_check }.to raise_not_found
-          expect { pull_access_check }.to raise_not_found
+          expect { push_access_check }.to raise_namespace_not_found
+          expect { pull_access_check }.to raise_namespace_not_found
         end
       end
     end
@@ -228,13 +229,6 @@ describe Gitlab::GitAccess do
       let(:project) { nil }
       let(:project_path) { "new-project" }
 
-      it 'blocks push and pull with "not found"' do
-        aggregate_failures do
-          expect { pull_access_check }.to raise_not_found
-          expect { push_access_check }.to raise_not_found
-        end
-      end
-
       context 'when user is allowed to create project in namespace' do
         let(:namespace_path) { user.namespace.path }
         let(:access) do
@@ -1219,6 +1213,10 @@ describe Gitlab::GitAccess do
     raise_error(Gitlab::GitAccess::NotFoundError, Gitlab::GitAccess::ERROR_MESSAGES[:project_not_found])
   end
 
+  def raise_namespace_not_found
+    raise_error(Gitlab::GitAccess::NotFoundError, Gitlab::GitAccess::ERROR_MESSAGES[:namespace_not_found])
+  end
+
   def build_authentication_abilities
     [
       :read_project,