fix: Prevent TestDataV2 from restoring an old flag builder when the flag key is a Symbol

lib/ldclient-rb/integrations/test_data_v2.rb

@@ -83,6 +83,7 @@ def initialize
       # @return [FlagBuilderV2] a flag configuration builder
       #
       def flag(key)
+        key = key.to_s
         existing_builder = @lock.with_read_lock do
           if @flag_builders.key?(key) && !@flag_builders[key].nil?
             @flag_builders[key]

lib/ldclient-rb/integrations/test_data_v2/flag_builder_v2.rb

@@ -26,7 +26,7 @@ class FlagBuilderV2
 
         # @api private
         def initialize(key)
-          @_key = key
+          @_key = key.to_s
           @_on = true
           @_variations = []
           @_off_variation = nil

spec/integrations/test_data_v2_spec.rb

@@ -91,6 +91,25 @@ module Integrations
         expect(td.flag('myflag').build(1)[:variations]).to eq([true, false])
       end
 
+      it 'starts a new flag builder after a preconfigured flag replaces a flag built with a symbol key' do
+        td = TestDataV2.data_source
+        td.update(td.flag(:myflag).variations('x', 'y'))
+        td.use_preconfigured_flag({ key: 'myflag', variations: ['a'] })
+        expect(td.flag(:myflag).build(1)[:variations]).to eq([true, false])
+      end
+
+      it 'gives a symbol key and a string key the same flag builder' do
+        td = TestDataV2.data_source
+        td.update(td.flag(:myflag).variations('x', 'y'))
+        expect(td.flag('myflag').build(1)[:variations]).to eq(['x', 'y'])
+      end
+
+      it 'stores a flag built with a symbol key with a string key' do
+        td = TestDataV2.data_source
+        td.update(td.flag(:myflag).variation_for_all(true))
+        expect(td.make_init_data[:flags][:myflag][:key]).to eq('myflag')
+      end
+
       it 'sends a preconfigured flag to a running data source' do
         td = TestDataV2.data_source
         source = LaunchDarkly::Impl::Integrations::TestData::TestDataSourceV2.new(td)