Fix error when loading empty config file

Author: Taucher2003

lib/sagittarius/configuration.rb

@@ -10,7 +10,7 @@ def self.config
       memoize(:config) do
         configured_files = ENV.fetch(CONFIG_FILES_ENV, nil)
         config_files(configured_files).reduce(defaults) do |config, config_file|
-          file_config = YAML.safe_load_file(config_file).deep_symbolize_keys
+          file_config = YAML.safe_load_file(config_file, fallback: {}).deep_symbolize_keys
           config.deep_merge(file_config)
         end
       rescue Errno::ENOENT

spec/lib/sagittarius/configuration_spec.rb

@@ -13,7 +13,7 @@
     end
 
     it 'loads the default config file' do
-      allow(YAML).to receive(:safe_load_file).with(default_config_file).and_return(
+      allow(YAML).to receive(:safe_load_file).with(default_config_file, fallback: {}).and_return(
         'rails' => {
           'web' => { 'threads' => 4 },
           'grpc' => { 'threads' => 8 },
@@ -29,7 +29,7 @@
     end
 
     it 'uses built-in defaults when the default config file does not exist' do
-      allow(YAML).to receive(:safe_load_file).with(default_config_file).and_raise(Errno::ENOENT)
+      allow(YAML).to receive(:safe_load_file).with(default_config_file, fallback: {}).and_raise(Errno::ENOENT)
 
       expect(described_class.config).to eq(described_class.defaults)
     end
@@ -39,19 +39,19 @@
         configured_files = ' config/base.yml,config/environment.yml, config/runtime.yml '
         allow(ENV).to receive(:fetch).with('SAGITTARIUS_CONFIG_FILES', nil)
                                      .and_return(configured_files)
-        allow(YAML).to receive(:safe_load_file).with('config/base.yml').and_return(
+        allow(YAML).to receive(:safe_load_file).with('config/base.yml', fallback: {}).and_return(
           'rails' => {
             'web' => { 'threads' => 4, 'port' => 4000 },
             'grpc' => { 'threads' => 4 },
           }
         )
-        allow(YAML).to receive(:safe_load_file).with('config/environment.yml').and_return(
+        allow(YAML).to receive(:safe_load_file).with('config/environment.yml', fallback: {}).and_return(
           'rails' => {
             'web' => { 'threads' => 8 },
             'grpc' => { 'host' => 'environment:50051' },
           }
         )
-        allow(YAML).to receive(:safe_load_file).with('config/runtime.yml').and_return(
+        allow(YAML).to receive(:safe_load_file).with('config/runtime.yml', fallback: {}).and_return(
           'rails' => {
             'web' => { 'threads' => 16 },
           }
@@ -70,13 +70,13 @@
       it 'loads each configured file in order' do
         described_class.config
 
-        expect(YAML).to have_received(:safe_load_file).ordered.with('config/base.yml')
-        expect(YAML).to have_received(:safe_load_file).ordered.with('config/environment.yml')
-        expect(YAML).to have_received(:safe_load_file).ordered.with('config/runtime.yml')
+        expect(YAML).to have_received(:safe_load_file).ordered.with('config/base.yml', fallback: {})
+        expect(YAML).to have_received(:safe_load_file).ordered.with('config/environment.yml', fallback: {})
+        expect(YAML).to have_received(:safe_load_file).ordered.with('config/runtime.yml', fallback: {})
       end
 
       it 'raises when a configured file does not exist' do
-        allow(YAML).to receive(:safe_load_file).with('config/environment.yml').and_raise(Errno::ENOENT)
+        allow(YAML).to receive(:safe_load_file).with('config/environment.yml', fallback: {}).and_raise(Errno::ENOENT)
 
         expect { described_class.config }.to raise_error(Errno::ENOENT)
       end
@@ -85,7 +85,10 @@
 
   describe '.defaults' do
     it 'matches the example config' do
-      example_config = YAML.safe_load_file(Rails.root.join('config/sagittarius.example.yml')).deep_symbolize_keys
+      example_config = YAML.safe_load_file(
+        Rails.root.join('config/sagittarius.example.yml'),
+        fallback: {}
+      ).deep_symbolize_keys
       expect(example_config).to eq(described_class.defaults)
     end
   end