1 files changed, 46 insertions, 0 deletions
diff --git a/app/models/ref_matcher.rb b/app/models/ref_matcher.rb
new file mode 100644
index 00000000000..fa7d2c0f06c
--- /dev/null
+++ b/app/models/ref_matcher.rb
@@ -0,0 +1,46 @@
+# frozen_string_literal: true
+
+class RefMatcher
+  def initialize(ref_name_or_pattern)
+    @ref_name_or_pattern = ref_name_or_pattern
+  end
+
+  # Returns all branches/tags (among the given list of refs [`Gitlab::Git::Branch`])
+  # that match the current protected ref.
+  def matching(refs)
+    refs.select { |ref| matches?(ref.name) }
+  end
+
+  # Checks if the protected ref matches the given ref name.
+  def matches?(ref_name)
+    return false if @ref_name_or_pattern.blank?
+
+    exact_match?(ref_name) || wildcard_match?(ref_name)
+  end
+
+  # Checks if this protected ref contains a wildcard
+  def wildcard?
+    @ref_name_or_pattern && @ref_name_or_pattern.include?('*')
+  end
+
+  protected
+
+  def exact_match?(ref_name)
+    @ref_name_or_pattern == ref_name
+  end
+
+  def wildcard_match?(ref_name)
+    return false unless wildcard?
+
+    wildcard_regex === ref_name
+  end
+
+  def wildcard_regex
+    @wildcard_regex ||= begin
+      name = @ref_name_or_pattern.gsub('*', 'STAR_DONT_ESCAPE')
+      quoted_name = Regexp.quote(name)
+      regex_string = quoted_name.gsub('STAR_DONT_ESCAPE', '.*?')
+      /\A#{regex_string}\z/
+    end
+  end
+end