Merge branch 'fix/import-error' into 'master'

Fix Import/Export error checking versions

Fixes small bug preventing the correct error message about Import/Export version being displayed.

Fixes https://gitlab.com/gitlab-org/gitlab-ce/issues/20536

- [x] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) entry added
- Tests
  - [x] Added for this feature/bug
  - [x] All builds are passing
- [x] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [x] Branch has no merge conflicts with `master` (if you do - rebase it please)
- [x] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

See merge request !5638
Signed-off-by: Rémy Coutable <remy@rymai.me>

CHANGELOG

@@ -4,6 +4,7 @@ v 8.10.4 (unreleased)
   - Don't close referenced upstream issues from a forked project.
   - Fixes issue with dropdowns `enter` key not working correctly. !5544
   - Fix Import/Export project import not working in HA mode. !5618
+  - Fix Import/Export error checking versions. !5638
 
 v 8.10.3
   - Fix Import/Export issue importing milestones and labels not associated properly. !5426

lib/gitlab/import_export/version_checker.rb

@@ -25,7 +25,7 @@ module Gitlab
 
       def verify_version!(version)
         if Gem::Version.new(version) > Gem::Version.new(Gitlab::ImportExport.version)
-          raise Gitlab::ImportExport::Error("Import version mismatch: Required <= #{Gitlab::ImportExport.version} but was #{version}")
+          raise Gitlab::ImportExport::Error.new("Import version mismatch: Required <= #{Gitlab::ImportExport.version} but was #{version}")
         else
           true
         end

spec/lib/gitlab/import_export/version_checker_spec.rb

+require 'spec_helper'
+
+describe Gitlab::ImportExport::VersionChecker, services: true do
+  describe 'bundle a project Git repo' do
+    let(:shared) { Gitlab::ImportExport::Shared.new(relative_path: '') }
+    let(:version) { Gitlab::ImportExport.version }
+
+    before do
+      allow(File).to receive(:open).and_return(version)
+    end
+
+    it 'returns true if Import/Export have the same version' do
+      expect(described_class.check!(shared: shared)).to be true
+    end
+
+    context 'newer version' do
+      let(:version) { '900.0'}
+
+      it 'returns false if export version is newer' do
+        expect(described_class.check!(shared: shared)).to be false
+      end
+
+      it 'shows the correct error message' do
+        described_class.check!(shared: shared)
+
+        expect(shared.errors.first).to eq("Import version mismatch: Required <= #{Gitlab::ImportExport.version} but was #{version}")
+      end
+    end
+  end
+end