test(config): add provider config tests

Signed-off-by: Marc Nuri <marc@marcnuri.com>

pkg/config/config_test.go

@@ -11,10 +11,25 @@ import (
 	"github.com/stretchr/testify/suite"
 )
 
-type ConfigSuite struct {
+type BaseConfigSuite struct {
 	suite.Suite
 }
 
+func (s *BaseConfigSuite) writeConfig(content string) string {
+	s.T().Helper()
+	tempDir := s.T().TempDir()
+	path := filepath.Join(tempDir, "config.toml")
+	err := os.WriteFile(path, []byte(content), 0644)
+	if err != nil {
+		s.T().Fatalf("Failed to write config file %s: %v", path, err)
+	}
+	return path
+}
+
+type ConfigSuite struct {
+	BaseConfigSuite
+}
+
 func (s *ConfigSuite) TestReadConfigMissingFile() {
 	config, err := Read("non-existent-config.toml")
 	s.Run("returns error for missing file", func() {
@@ -159,17 +174,6 @@ func (s *ConfigSuite) TestReadConfigValidPreservesDefaultsForMissingFields() {
 	})
 }
 
-func (s *ConfigSuite) writeConfig(content string) string {
-	s.T().Helper()
-	tempDir := s.T().TempDir()
-	path := filepath.Join(tempDir, "config.toml")
-	err := os.WriteFile(path, []byte(content), 0644)
-	if err != nil {
-		s.T().Fatalf("Failed to write config file %s: %v", path, err)
-	}
-	return path
-}
-
 func TestConfig(t *testing.T) {
 	suite.Run(t, new(ConfigSuite))
 }

pkg/config/provider_config_test.go

@@ -0,0 +1,157 @@
+package config
+
+import (
+	"errors"
+	"testing"
+
+	"github.com/BurntSushi/toml"
+	"github.com/stretchr/testify/suite"
+)
+
+type ProviderConfigSuite struct {
+	BaseConfigSuite
+	originalProviderConfigParsers map[string]ProviderConfigParser
+}
+
+func (s *ProviderConfigSuite) SetupTest() {
+	s.originalProviderConfigParsers = make(map[string]ProviderConfigParser)
+	for k, v := range providerConfigParsers {
+		s.originalProviderConfigParsers[k] = v
+	}
+}
+
+func (s *ProviderConfigSuite) TearDownTest() {
+	providerConfigParsers = make(map[string]ProviderConfigParser)
+	for k, v := range s.originalProviderConfigParsers {
+		providerConfigParsers[k] = v
+	}
+}
+
+type ProviderConfigForTest struct {
+	BoolProp bool   `toml:"bool_prop"`
+	StrProp  string `toml:"str_prop"`
+	IntProp  int    `toml:"int_prop"`
+}
+
+var _ ProviderConfig = (*ProviderConfigForTest)(nil)
+
+func (p *ProviderConfigForTest) Validate() error {
+	if p.StrProp == "force-error" {
+		return errors.New("validation error forced by test")
+	}
+	return nil
+}
+
+func providerConfigForTestParser(primitive toml.Primitive, md toml.MetaData) (ProviderConfig, error) {
+	var providerConfigForTest ProviderConfigForTest
+	if err := md.PrimitiveDecode(primitive, &providerConfigForTest); err != nil {
+		return nil, err
+	}
+	return &providerConfigForTest, nil
+}
+
+func (s *ProviderConfigSuite) TestRegisterProviderConfig() {
+	s.Run("panics when registering duplicate provider config parser", func() {
+		s.Panics(func() {
+			RegisterProviderConfig("test", providerConfigForTestParser)
+			RegisterProviderConfig("test", providerConfigForTestParser)
+		}, "Expected panic when registering duplicate provider config parser")
+	})
+}
+
+func (s *ProviderConfigSuite) TestReadConfigValid() {
+	RegisterProviderConfig("test", providerConfigForTestParser)
+	validConfigPath := s.writeConfig(`
+		cluster_provider_strategy = "test"
+		[cluster_provider_configs.test]
+		bool_prop = true
+		str_prop = "a string"
+		int_prop = 42
+	`)
+
+	config, err := Read(validConfigPath)
+	s.Run("returns no error for valid file with registered provider config", func() {
+		s.Require().NoError(err, "Expected no error for valid file, got %v", err)
+	})
+	s.Run("returns config for valid file with registered provider config", func() {
+		s.Require().NotNil(config, "Expected non-nil config for valid file")
+	})
+	s.Run("parses provider config correctly", func() {
+		providerConfig, ok := config.GetProviderConfig("test")
+		s.Require().True(ok, "Expected to find provider config for strategy 'test'")
+		s.Require().NotNil(providerConfig, "Expected non-nil provider config for strategy 'test'")
+		testProviderConfig, ok := providerConfig.(*ProviderConfigForTest)
+		s.Require().True(ok, "Expected provider config to be of type *ProviderConfigForTest")
+		s.Equal(true, testProviderConfig.BoolProp, "Expected BoolProp to be true")
+		s.Equal("a string", testProviderConfig.StrProp, "Expected StrProp to be 'a string'")
+		s.Equal(42, testProviderConfig.IntProp, "Expected IntProp to be 42")
+	})
+}
+
+func (s *ProviderConfigSuite) TestReadConfigInvalidProviderConfig() {
+	RegisterProviderConfig("test", providerConfigForTestParser)
+	invalidConfigPath := s.writeConfig(`
+		cluster_provider_strategy = "test"
+		[cluster_provider_configs.test]
+		bool_prop = true
+		str_prop = "force-error"
+		int_prop = 42
+	`)
+
+	config, err := Read(invalidConfigPath)
+	s.Run("returns error for invalid provider config", func() {
+		s.Require().NotNil(err, "Expected error for invalid provider config, got nil")
+		s.ErrorContains(err, "validation error forced by test", "Expected validation error from provider config")
+	})
+	s.Run("returns nil config for invalid provider config", func() {
+		s.Nil(config, "Expected nil config for invalid provider config")
+	})
+}
+
+func (s *ProviderConfigSuite) TestReadConfigUnregisteredProviderConfig() {
+	invalidConfigPath := s.writeConfig(`
+		cluster_provider_strategy = "unregistered"
+		[cluster_provider_configs.unregistered]
+		bool_prop = true
+		str_prop = "a string"
+		int_prop = 42
+	`)
+
+	config, err := Read(invalidConfigPath)
+	s.Run("returns no error for unregistered provider config", func() {
+		s.Require().NoError(err, "Expected no error for unregistered provider config, got %v", err)
+	})
+	s.Run("returns config for unregistered provider config", func() {
+		s.Require().NotNil(config, "Expected non-nil config for unregistered provider config")
+	})
+	s.Run("does not parse unregistered provider config", func() {
+		_, ok := config.GetProviderConfig("unregistered")
+		s.Require().False(ok, "Expected no provider config for unregistered strategy")
+	})
+}
+
+func (s *ProviderConfigSuite) TestReadConfigParserError() {
+	RegisterProviderConfig("test", func(primitive toml.Primitive, md toml.MetaData) (ProviderConfig, error) {
+		return nil, errors.New("parser error forced by test")
+	})
+	invalidConfigPath := s.writeConfig(`
+		cluster_provider_strategy = "test"
+		[cluster_provider_configs.test]
+		bool_prop = true
+		str_prop = "a string"
+		int_prop = 42
+	`)
+
+	config, err := Read(invalidConfigPath)
+	s.Run("returns error for provider config parser error", func() {
+		s.Require().NotNil(err, "Expected error for provider config parser error, got nil")
+		s.ErrorContains(err, "parser error forced by test", "Expected parser error from provider config")
+	})
+	s.Run("returns nil config for provider config parser error", func() {
+		s.Nil(config, "Expected nil config for provider config parser error")
+	})
+}
+
+func TestProviderConfig(t *testing.T) {
+	suite.Run(t, new(ProviderConfigSuite))
+}