RR-583: Create non-nilable CodeTeams.find!

lib/code_teams.rb

@@ -13,28 +13,27 @@ module CodeTeams
   extend T::Sig
 
   class IncorrectPublicApiUsageError < StandardError; end
+  class TeamNotFoundError < StandardError; end
 
   UNKNOWN_TEAM_STRING = 'Unknown Team'
   @plugins_registered = T.let(false, T::Boolean)
 
   sig { returns(T::Array[Team]) }
   def self.all
-    @all = T.let(@all, T.nilable(T::Array[Team]))
-    @all ||= for_directory('config/teams')
+    @all ||= T.let(for_directory('config/teams'), T.nilable(T::Array[Team]))
   end
 
   sig { params(name: String).returns(T.nilable(Team)) }
   def self.find(name)
-    @index_by_name = T.let(@index_by_name, T.nilable(T::Hash[String, CodeTeams::Team]))
-    @index_by_name ||= begin
-      result = {}
-      all.each { |t| result[t.name] = t }
-      result
-    end
-
+    @index_by_name ||= T.let(all.to_h { |t| [t.name, t] }, T.nilable(T::Hash[String, CodeTeams::Team]))
     @index_by_name[name]
   end
 
+  sig { params(name: String).returns(Team) }
+  def self.find!(name)
+    find(name) || raise(TeamNotFoundError, "No team found with name: #{name}")
+  end
+
   sig { params(dir: String).returns(T::Array[Team]) }
   def self.for_directory(dir)
     unless @plugins_registered

spec/lib/code_teams_spec.rb

@@ -37,6 +37,34 @@
     end
   end
 
+  describe '.find' do
+    it 'returns the team when found' do
+      team = described_class.find('My Team')
+      expect(team).to be_a(CodeTeams::Team)
+      expect(team.name).to eq('My Team')
+    end
+
+    it 'returns nil when the team is not found' do
+      team = described_class.find('Nonexistent Team')
+      expect(team).to be_nil
+    end
+  end
+
+  describe '.find!' do
+    it 'returns the team when found' do
+      team = described_class.find!('My Team')
+      expect(team).to be_a(CodeTeams::Team)
+      expect(team.name).to eq('My Team')
+    end
+
+    it 'raises TeamNotFoundError when the team is not found' do
+      expect { described_class.find!('Nonexistent Team') }.to raise_error(
+        CodeTeams::TeamNotFoundError,
+        'No team found with name: Nonexistent Team'
+      )
+    end
+  end
+
   describe 'validation_errors' do
     subject(:validation_errors) { described_class.validation_errors(described_class.all) }