1 files changed, 96 insertions, 0 deletions
diff --git a/spec/lib/gitlab/ci/pipeline/expression/lexeme/pattern_spec.rb b/spec/lib/gitlab/ci/pipeline/expression/lexeme/pattern_spec.rb
new file mode 100644
index 00000000000..3ebc2e94727
--- /dev/null
+++ b/spec/lib/gitlab/ci/pipeline/expression/lexeme/pattern_spec.rb
@@ -0,0 +1,96 @@
+require 'fast_spec_helper'
+
+describe Gitlab::Ci::Pipeline::Expression::Lexeme::Pattern do
+  describe '.build' do
+    it 'creates a new instance of the token' do
+      expect(described_class.build('/.*/'))
+        .to be_a(described_class)
+    end
+
+    it 'raises an error if pattern is invalid' do
+      expect { described_class.build('/ some ( thin/i') }
+        .to raise_error(Gitlab::Ci::Pipeline::Expression::Lexer::SyntaxError)
+    end
+  end
+
+  describe '.type' do
+    it 'is a value lexeme' do
+      expect(described_class.type).to eq :value
+    end
+  end
+
+  describe '.scan' do
+    it 'correctly identifies a pattern token' do
+      scanner = StringScanner.new('/pattern/')
+
+      token = described_class.scan(scanner)
+
+      expect(token).not_to be_nil
+      expect(token.build.evaluate)
+        .to eq Gitlab::UntrustedRegexp.new('pattern')
+    end
+
+    it 'is a greedy scanner for regexp boundaries' do
+      scanner = StringScanner.new('/some .* / pattern/')
+
+      token = described_class.scan(scanner)
+
+      expect(token).not_to be_nil
+      expect(token.build.evaluate)
+        .to eq Gitlab::UntrustedRegexp.new('some .* / pattern')
+    end
+
+    it 'does not allow to use an empty pattern' do
+      scanner = StringScanner.new(%(//))
+
+      token = described_class.scan(scanner)
+
+      expect(token).to be_nil
+    end
+
+    it 'support single flag' do
+      scanner = StringScanner.new('/pattern/i')
+
+      token = described_class.scan(scanner)
+
+      expect(token).not_to be_nil
+      expect(token.build.evaluate)
+        .to eq Gitlab::UntrustedRegexp.new('(?i)pattern')
+    end
+
+    it 'support multiple flags' do
+      scanner = StringScanner.new('/pattern/im')
+
+      token = described_class.scan(scanner)
+
+      expect(token).not_to be_nil
+      expect(token.build.evaluate)
+        .to eq Gitlab::UntrustedRegexp.new('(?im)pattern')
+    end
+
+    it 'does not support arbitrary flags' do
+      scanner = StringScanner.new('/pattern/x')
+
+      token = described_class.scan(scanner)
+
+      expect(token).to be_nil
+    end
+  end
+
+  describe '#evaluate' do
+    it 'returns a regular expression' do
+      regexp = described_class.new('/abc/')
+
+      expect(regexp.evaluate).to eq Gitlab::UntrustedRegexp.new('abc')
+    end
+
+    it 'raises error if evaluated regexp is not valid' do
+      allow(Gitlab::UntrustedRegexp).to receive(:valid?).and_return(true)
+
+      regexp = described_class.new('/invalid ( .*/')
+
+      expect { regexp.evaluate }
+        .to raise_error(Gitlab::Ci::Pipeline::Expression::RuntimeError)
+    end
+  end
+end