absurl: export a base url var for testing

transform/absurl.go

@@ -5,6 +5,9 @@ import (
 	"sync"
 )
 
+// to be used in tests; the live site will get its value from Viper.
+var AbsBaseUrl string
+
 var absURLInit sync.Once
 var ar *absURLReplacer
 
@@ -42,6 +45,14 @@ func absURLInXMLFromReplacer(ar *absURLReplacer) (trs []link, err error) {
 
 func initAbsURLReplacer() {
 	absURLInit.Do(func() {
-		ar = newAbsURLReplacer(viper.GetString("BaseURL"))
+		var url string
+
+		if AbsBaseUrl != "" {
+			url = AbsBaseUrl
+		} else {
+			url = viper.GetString("BaseURL")
+		}
+
+		ar = newAbsURLReplacer(url)
 	})
 }