ls() workaround

Workaround for issue #170

library/src/main/scala/giter8/Ls.scala

@@ -0,0 +1,30 @@
+/*
+ * Copyright 2017 by foundweekends project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package giter8
+
+import scala.util.parsing.combinator._
+
+object Ls extends JavaTokenParsers {
+  private val owner, name = """[\w\-\.]+""".r
+  private val spec =
+    "ls" ~> "(" ~> owner ~ ("," ~> name) <~ ")" ^^ {
+      case owner ~ name => (owner, name)
+    }
+
+  def unapply(value: String): Option[(String, String)] =
+    Some(parse(spec, value)).filter { _.successful }.map { _.get }
+}

library/src/main/scala/maven.scala

@@ -77,8 +77,13 @@ object Maven extends JavaTokenParsers with MavenHelper {
     }
   }
 
+  def lsIsGone(artifact: String): VersionE =
+    Left("ls() function is deprecated. " +
+      s"Use maven() function to get latest version of ${artifact.trim}.")
+
   def lookup(rawDefaults: G8.OrderedProperties): Either[String, G8.OrderedProperties] = {
     val defaults = rawDefaults.map {
+      case (k, Ls(owner, name))                  => k -> lsIsGone(name)
       case (k, Maven(org, name, Some("stable"))) => k -> latestStableVersion(org, name)
       case (k, Maven(org, name, _))              => k -> latestVersion(org, name)
       case (k, value)                            => k -> Right(value)