Adds specs for pipeline expressions raw token

spec/lib/gitlab/ci/pipeline/expression/token_spec.rb

+require 'spec_helper'
+
+describe Gitlab::Ci::Pipeline::Expression::Token do
+  let(:value) { '$VARIABLE' }
+  let(:lexeme) { Gitlab::Ci::Pipeline::Expression::Lexeme::Variable }
+
+  subject { described_class.new(value, lexeme) }
+
+  describe '#value' do
+    it 'returns raw token value' do
+      expect(subject.value).to eq value
+    end
+  end
+
+  describe '#lexeme' do
+    it 'returns raw token lexeme' do
+      expect(subject.lexeme).to eq lexeme
+    end
+  end
+
+  describe '#build' do
+    it 'delegates to lexeme after adding a value' do
+      expect(lexeme).to receive(:build)
+        .with(value, 'some', 'args')
+
+      subject.build('some', 'args')
+    end
+
+    it 'allows passing only required arguments' do
+      expect(subject.build).to be_an_instance_of(lexeme)
+    end
+  end
+
+  describe '#type' do
+    it 'delegates type query to the lexeme' do
+      expect(subject.type).to eq :value
+    end
+  end
+
+  describe '#to_lexeme' do
+    it 'returns raw lexeme syntax component name' do
+      expect(subject.to_lexeme).to eq 'variable'
+    end
+  end
+end