Merge pull request #314 from alexarchambault/topic/fix

Fix

cli/src/main/scala-2.11/coursier/cli/Bootstrap.scala

@@ -130,7 +130,11 @@ case class Bootstrap(
   if (nonHttpUrls.nonEmpty)
     Console.err.println(s"Warning: non HTTP URLs:\n${nonHttpUrls.mkString("\n")}")
 
-  val mainClass = helper.retainedMainClass
+  val mainClass =
+    if (options.mainClass.isEmpty)
+      helper.retainedMainClass
+    else
+      options.mainClass
 
   val buffer = new ByteArrayOutputStream
 

cli/src/main/scala-2.11/coursier/cli/Helper.scala

@@ -664,10 +664,7 @@ class Helper(
     }
 
     val mainClass =
-      if (mainClasses.isEmpty) {
-        Helper.errPrintln("No main class found. Specify one with -M or --main.")
-        sys.exit(255)
-      } else if (mainClasses.size == 1) {
+      if (mainClasses.size == 1) {
         val (_, mainClass) = mainClasses.head
         mainClass
       } else {

cli/src/main/scala-2.11/coursier/cli/Launch.scala

@@ -80,22 +80,28 @@ case class Launch(
     isolated = options.isolated
   )
 
+  val mainClass =
+    if (options.mainClass.isEmpty)
+      helper.retainedMainClass
+    else
+      options.mainClass
+
   val cls =
-    try helper.loader.loadClass(helper.retainedMainClass)
+    try helper.loader.loadClass(mainClass)
     catch { case e: ClassNotFoundException =>
-      Helper.errPrintln(s"Error: class ${helper.retainedMainClass} not found")
+      Helper.errPrintln(s"Error: class $mainClass not found")
       sys.exit(255)
     }
   val method =
     try cls.getMethod("main", classOf[Array[String]])
     catch { case e: NoSuchMethodException =>
-      Helper.errPrintln(s"Error: method main not found in ${helper.retainedMainClass}")
+      Helper.errPrintln(s"Error: method main not found in $mainClass")
       sys.exit(255)
     }
   method.setAccessible(true)
 
   if (options.common.verbosityLevel >= 2)
-    Helper.errPrintln(s"Launching ${helper.retainedMainClass} ${userArgs.mkString(" ")}")
+    Helper.errPrintln(s"Launching $mainClass ${userArgs.mkString(" ")}")
   else if (options.common.verbosityLevel == 1)
     Helper.errPrintln(s"Launching")