优化

app/src/main/java/io/legado/app/help/source/RssSourceExtensions.kt

@@ -12,27 +12,27 @@ private fun RssSource.getSortUrlsKey(): String {
     return MD5Utils.md5Encode(sourceUrl + sortUrl)
 }
 
-suspend fun RssSource.sortUrls(): List<Pair<String, String>> =
-    arrayListOf<Pair<String, String>>().apply {
+suspend fun RssSource.sortUrls(): List<Pair<String, String>> {
+    return arrayListOf<Pair<String, String>>().apply {
         val sortUrlsKey = getSortUrlsKey()
         withContext(Dispatchers.IO) {
             kotlin.runCatching {
-                var a = sortUrl
+                var str = sortUrl
                 if (sortUrl?.startsWith("<js>", false) == true
                     || sortUrl?.startsWith("@js:", false) == true
                 ) {
-                    a = aCache.getAsString(sortUrlsKey) ?: ""
-                    if (a.isBlank()) {
+                    str = aCache.getAsString(sortUrlsKey)
+                    if (str.isNullOrBlank()) {
                         val jsStr = if (sortUrl!!.startsWith("@")) {
                             sortUrl!!.substring(4)
                         } else {
                             sortUrl!!.substring(4, sortUrl!!.lastIndexOf("<"))
                         }
-                        a = evalJS(jsStr).toString()
-                        aCache.put(sortUrlsKey, a)
+                        str = evalJS(jsStr).toString()
+                        aCache.put(sortUrlsKey, str)
                     }
                 }
-                a?.split("(&&|\n)+".toRegex())?.forEach { c ->
+                str?.split("(&&|\n)+".toRegex())?.forEach { c ->
                     val d = c.split("::")
                     if (d.size > 1)
                         add(Pair(d[0], d[1]))
@@ -43,6 +43,7 @@ suspend fun RssSource.sortUrls(): List<Pair<String, String>> =
             }
         }
     }
+}
 
 suspend fun RssSource.removeSortCache() {
     withContext(Dispatchers.IO) {