pkg/config: turn ComposeProviders into attributedstring.Slice

Signed-off-by: Valentin Rothberg <vrothberg@redhat.com>

common/pkg/config/config.go

@@ -271,7 +271,7 @@ type EngineConfig struct {
 	// compose command.  The first found provider is used for execution.
 	// Can be an absolute and relative path or a (file) name.  Make sure to
 	// expand the return items via `os.ExpandEnv`.
-	ComposeProviders []string `toml:"compose_providers,omitempty"`
+	ComposeProviders attributedstring.Slice `toml:"compose_providers,omitempty"`
 
 	// ComposeWarningLogs emits logs on each invocation of the compose
 	// command indicating that an external compose provider is being

common/pkg/config/config_local_test.go

@@ -489,12 +489,12 @@ var _ = Describe("Config Local", func() {
 		// Given
 		config, err := New(nil)
 		gomega.Expect(err).To(gomega.BeNil())
-		gomega.Expect(config.Engine.ComposeProviders).To(gomega.Equal(getDefaultComposeProviders())) // no hard-coding to work on all platforms
+		gomega.Expect(config.Engine.ComposeProviders.Get()).To(gomega.Equal(getDefaultComposeProviders())) // no hard-coding to work on all platforms
 		// When
 		config2, err := NewConfig("testdata/containers_default.conf")
 		// Then
 		gomega.Expect(err).To(gomega.BeNil())
-		gomega.Expect(config2.Engine.ComposeProviders).To(gomega.Equal([]string{"/some/thing/else", "/than/before"}))
+		gomega.Expect(config2.Engine.ComposeProviders.Get()).To(gomega.Equal([]string{"/some/thing/else", "/than/before"}))
 	})
 
 	It("AddCompression", func() {

common/pkg/config/default.go

@@ -288,7 +288,7 @@ func defaultEngineConfig() (*EngineConfig, error) {
 	c.EventsLogFileMaxSize = eventsLogMaxSize(DefaultEventsLogSizeMax)
 
 	c.CompatAPIEnforceDockerHub = true
-	c.ComposeProviders = getDefaultComposeProviders() // may vary across supported platforms
+	c.ComposeProviders = attributedstring.Slice{Values: getDefaultComposeProviders()} // may vary across supported platforms
 	c.ComposeWarningLogs = true
 
 	if path, ok := os.LookupEnv("CONTAINERS_STORAGE_CONF"); ok {