cucumber#154, RunCukesTest.scala uses ScalaBackend.loadGlue which cal…

…ls ClasspathResourceLoader().instantiateSubclasses which didn't check if the class had a valid constructor given the arguments. ScalaDslTest.scala holds multiple internal ScalaDsl instances which are compiled to classes implementing ScalaDsl but with no valid constructor. These were being picked up by the ClasspathResourceLoader causing the RunCukesTest to fail at load time

core/src/main/java/cucumber/io/ClasspathResourceLoader.java

@@ -44,7 +44,7 @@ public <T> T instantiateExactlyOneSubclass(Class<T> parentType, String packagePa
     public <T> Collection<? extends T> instantiateSubclasses(Class<T> parentType, String packagePath, Class[] constructorParams, Object[] constructorArgs) {
         Collection<T> result = new HashSet<T>();
         for (Class<? extends T> clazz : getDescendants(parentType, packagePath)) {
-            if (Utils.isInstantiable(clazz)) {
+            if (Utils.isInstantiable(clazz) && Utils.hasConstructor(clazz, constructorParams)) {
                 result.add(newInstance(constructorParams, constructorArgs, clazz));
             }
         }

core/src/main/java/cucumber/runtime/Utils.java

@@ -17,6 +17,15 @@ public static <T> List<T> listOf(int size, T obj) {
     public static boolean isInstantiable(Class<?> clazz) {
         return Modifier.isPublic(clazz.getModifiers()) && !Modifier.isAbstract(clazz.getModifiers());
     }
+
+    public static boolean hasConstructor(Class<?> clazz, Class[] paramTypes) {
+      try {
+        clazz.getConstructor(paramTypes);
+        return true;
+      } catch (NoSuchMethodException e) {
+        return false;
+      }
+    }
 
     public static String packagePath(Class clazz) {
         return packagePath(packageName(clazz.getName()));

pom.xml

@@ -60,12 +60,11 @@
                 <artifactId>cucumber-picocontainer</artifactId>
                 <version>${project.version}</version>
             </dependency>
-            <!-- Not cooking scala, should not include it in the depends
             <dependency>
                 <groupId>info.cukes</groupId>
                 <artifactId>cucumber-scala</artifactId>
                 <version>${project.version}</version>
-            </dependency> -->
+            </dependency>
             <dependency>
                 <groupId>info.cukes</groupId>
                 <artifactId>gherkin</artifactId>
@@ -254,8 +253,8 @@
         <module>rhino</module>
         <module>java</module>
         <module>clojure</module>
+        <module>scala</module>
 
-        <!--<module>scala</module>-->
         <!--<module>openejb</module>-->
     </modules>
 

scala/pom.xml

@@ -8,7 +8,7 @@
         <groupId>info.cukes</groupId>
         <artifactId>cucumber-jvm</artifactId>
         <relativePath>../pom.xml</relativePath>
-        <version>1.0.0.RC7-SNAPSHOT</version>
+        <version>1.0.0.RC11-SNAPSHOT</version>
     </parent>
 
     <artifactId>cucumber-scala</artifactId>