feat: added split fitler (#187)

Sources/Extension.swift

@@ -57,6 +57,7 @@ class DefaultExtension: Extension {
     registerFilter("uppercase", filter: uppercase)
     registerFilter("lowercase", filter: lowercase)
     registerFilter("join", filter: joinFilter)
+    registerFilter("split", filter: splitFilter)
   }
 }
 

Sources/Filters.swift

@@ -40,3 +40,16 @@ func joinFilter(value: Any?, arguments: [Any?]) throws -> Any? {
 
   return value
 }
+
+func splitFilter(value: Any?, arguments: [Any?]) throws -> Any? {
+  guard arguments.count < 2 else {
+    throw TemplateSyntaxError("'split' filter takes a single argument")
+  }
+
+  let separator = stringify(arguments.first ?? " ")
+  if let value = value as? String {
+    return value.components(separatedBy: separator)
+  }
+
+  return value
+}