Add API::Helpers::Version and expose API root URL

This commits adds a new class that is supposed to represent Grape API
version, like `v3` or `v4`.

2 files changed, 27 insertions, 16 deletions

diff --git a/spec/lib/api/api_spec.rb b/spec/lib/api/api_spec.rb
index 31881551980..ceef0b41e59 100644
--- a/spec/lib/api/api_spec.rb
+++ b/spec/lib/api/api_spec.rb
@@ -15,22 +15,7 @@ describe API::API do
 
   describe '.versions' do
     it 'returns all available versions' do
-      expect(described_class.versions).to eq ['v3', 'v4']
-    end
-  end
-
-  describe '.root_path' do
-    it 'returns predefined API version path' do
-      expect(described_class.root_path).to eq '/api/v4'
-    end
-
-    it 'returns a version provided as keyword argument' do
-      expect(described_class.root_path(version: 'v3')).to eq '/api/v3'
-    end
-
-    it 'raises an error if version is not known' do
-      expect { described_class.root_path(version: 'v10') }
-        .to raise_error ArgumentError
+      expect(described_class.versions).to eq %w[v3 v4]
     end
   end
 end
diff --git a/spec/lib/api/helpers/version_spec.rb b/spec/lib/api/helpers/version_spec.rb
new file mode 100644
index 00000000000..63e7e1e6e95
--- /dev/null
+++ b/spec/lib/api/helpers/version_spec.rb
@@ -0,0 +1,26 @@
+require 'spec_helper'
+
+describe API::Helpers::Version do
+  describe '.new' do
+    it 'is possible to initialize it with existing API version' do
+      expect(described_class.new('v4').to_s).to eq 'v4'
+    end
+
+    it 'raises an error when unsupported API version is provided' do
+      expect { described_class.new('v111') }.to raise_error ArgumentError
+    end
+  end
+
+  describe '#root_path' do
+    it 'returns a root path of the API version' do
+      expect(described_class.new('v4').root_path).to eq '/api/v4'
+    end
+  end
+
+  describe '#root_url' do
+    it 'returns an URL for a root path for the API version' do
+      expect(described_class.new('v4').root_url)
+        .to match %r{^http?://.*/api/v4$}
+    end
+  end
+end