fixed breaking variables lists and filters by spaces

Sources/Tokenizer.swift

@@ -36,10 +36,37 @@ extension String {
       components.append(word)
     }
 
-    return components
+    return smartJoin(components)
   }
 }
 
+// joins back components around characters used in variables lists and filters
+private func smartJoin(_ components: [String]) -> [String] {
+  var joinedComponents = components
+  // convert ["a", "|", "b"] and ["a|", "b"] to ["a|b"]
+  // do not allow ["a", "|b"]
+  for char in [",", "|", ":"] {
+    while let index = joinedComponents.index(of: char) {
+      if index > 0 {
+        joinedComponents[index-1] += char
+
+        if joinedComponents.count > index + 1 {
+          joinedComponents[index-1] += joinedComponents[index+1]
+          joinedComponents.remove(at: index+1)
+        }
+      }
+      joinedComponents.remove(at: index)
+    }
+    while let index = joinedComponents.index(where: { $0.hasSuffix(char) }) {
+      if joinedComponents.count > index {
+        joinedComponents[index] += joinedComponents[index+1]
+        joinedComponents.remove(at: index+1)
+      }
+    }
+  }
+  return joinedComponents
+}
+
 
 public enum Token : Equatable {
   /// A token representing a piece of text.

Tests/StencilTests/ForNodeSpec.swift

@@ -104,8 +104,8 @@ func testForNode() {
         try expect(try node.render(context)) == "empty"
     }
 
-    $0.it("can render a filter") {
-      let templateString = "{% for article in ars|default:articles %}" +
+    $0.it("can render a filter with spaces") {
+      let templateString = "{% for article in ars | default: a, b , articles %}" +
         "- {{ article.title }} by {{ article.author }}.\n" +
         "{% endfor %}\n"
 
@@ -128,7 +128,7 @@ func testForNode() {
     }
 
     $0.it("can iterate over dictionary") {
-      let templateString = "{% for key,value in dict %}" +
+      let templateString = "{% for key, value in dict %}" +
         "{{ key }}: {{ value }}\n" +
         "{% endfor %}\n"