1 files changed, 30 insertions, 0 deletions
diff --git a/spec/lib/gitlab/ci/pipeline/expression/lexeme/matches_spec.rb b/spec/lib/gitlab/ci/pipeline/expression/lexeme/matches_spec.rb
index a6fdec832a3..a527783ffac 100644
--- a/spec/lib/gitlab/ci/pipeline/expression/lexeme/matches_spec.rb
+++ b/spec/lib/gitlab/ci/pipeline/expression/lexeme/matches_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'fast_spec_helper'
 require_dependency 're2'
 
@@ -67,6 +69,34 @@ describe Gitlab::Ci::Pipeline::Expression::Lexeme::Matches do
       it { is_expected.to eq(false) }
     end
 
+    context 'when right is nil' do
+      let(:left_value)  { 'my-awesome-string' }
+      let(:right_value) { nil }
+
+      it { is_expected.to eq(false) }
+    end
+
+    context 'when left and right are nil' do
+      let(:left_value)  { nil }
+      let(:right_value) { nil }
+
+      it { is_expected.to eq(false) }
+    end
+
+    context 'when left is an empty string' do
+      let(:left_value)  { '' }
+      let(:right_value) { Gitlab::UntrustedRegexp.new('pattern') }
+
+      it { is_expected.to eq(false) }
+    end
+
+    context 'when left and right are empty strings' do
+      let(:left_value)  { '' }
+      let(:right_value) { Gitlab::UntrustedRegexp.new('') }
+
+      it { is_expected.to eq(true) }
+    end
+
     context 'when left is a multiline string and matches right' do
       let(:left_value) do
         <<~TEXT