commands, hugolib: Deprecate disable404, disableRSS, disableSitemap, disableRobotsTXT

Use disableKinds instead.

Fixes #3345

commands/hugo.go

@@ -467,6 +467,19 @@ func (c *commandeer) initializeFlags(cmd *cobra.Command) {
 		"noChmod",
 	}
 
+	// Remove these in Hugo 0.23.
+	if flagChanged(cmd.Flags(), "disable404") {
+		helpers.Deprecated("command line", "--disable404", "Use --disableKinds=404", false)
+	}
+
+	if flagChanged(cmd.Flags(), "disableRSS") {
+		helpers.Deprecated("command line", "--disableRSS", "Use --disableKinds=RSS", false)
+	}
+
+	if flagChanged(cmd.Flags(), "disableSitemap") {
+		helpers.Deprecated("command line", "--disableSitemap", "Use --disableKinds=sitemap", false)
+	}
+
 	for _, key := range persFlagKeys {
 		c.setValueFromFlag(cmd.PersistentFlags(), key)
 	}

hugolib/config.go

@@ -49,6 +49,23 @@ func LoadConfig(fs afero.Fs, relativeSourcePath, configFilename string) (*viper.
 
 	v.RegisterAlias("indexes", "taxonomies")
 
+	// Remove these in Hugo 0.23.
+	if v.IsSet("disable404") {
+		helpers.Deprecated("site config", "disable404", "Use disableKinds=[\"404\"]", false)
+	}
+
+	if v.IsSet("disableRSS") {
+		helpers.Deprecated("site config", "disableRSS", "Use disableKinds=[\"RSS\"]", false)
+	}
+
+	if v.IsSet("disableSitemap") {
+		helpers.Deprecated("site config", "disableSitemap", "Use disableKinds= [\"sitemap\"]", false)
+	}
+
+	if v.IsSet("disableRobotsTXT") {
+		helpers.Deprecated("site config", "disableRobotsTXT", "Use disableKinds= [\"robotsTXT\"]", false)
+	}
+
 	loadDefaultSettingsFor(v)
 
 	return v, nil