Short-circuit build coverage extraction for empty regexes

2 files changed, 25 insertions, 3 deletions

diff --git a/spec/lib/gitlab/ci/trace/stream_spec.rb b/spec/lib/gitlab/ci/trace/stream_spec.rb
index 3a132fb9989..8b925fd4e22 100644
--- a/spec/lib/gitlab/ci/trace/stream_spec.rb
+++ b/spec/lib/gitlab/ci/trace/stream_spec.rb
@@ -307,5 +307,27 @@ describe Gitlab::Ci::Trace::Stream do
 
       it { is_expected.to eq('65') }
     end
+
+    context 'empty regex' do
+      let(:data) { 'foo' }
+      let(:regex) { '' }
+
+      it 'skips processing' do
+        expect(stream).not_to receive(:read)
+
+        is_expected.to be_nil
+      end
+    end
+
+    context 'nil regex' do
+      let(:data) { 'foo' }
+      let(:regex) { nil }
+
+      it 'skips processing' do
+        expect(stream).not_to receive(:read)
+
+        is_expected.to be_nil
+      end
+    end
   end
 end
diff --git a/spec/lib/gitlab/untrusted_regexp_spec.rb b/spec/lib/gitlab/untrusted_regexp_spec.rb
index a2ef2a27e4c..21d47b7897a 100644
--- a/spec/lib/gitlab/untrusted_regexp_spec.rb
+++ b/spec/lib/gitlab/untrusted_regexp_spec.rb
@@ -55,7 +55,7 @@ describe Gitlab::UntrustedRegexp do
       let(:text) { 'foo' }
 
       it 'returns an array of empty matches' do
-        is_expected.to eq(['', '', ''])
+        is_expected.to eq([''])
       end
     end
 
@@ -63,8 +63,8 @@ describe Gitlab::UntrustedRegexp do
       let(:regexp) { '()' }
       let(:text) { 'foo' }
 
-      it 'returns arrays of empty matches in an array' do
-        is_expected.to eq([[''], [''], ['']])
+      it 'returns an array of empty matches in an array' do
+        is_expected.to eq([['']])
       end
     end