Validation of VoidReturn for @BINDS. Fixes #23

src/main/kotlin/com/madrapps/dagger/validation/BindsProblem.kt

@@ -38,6 +38,7 @@ object BindsProblem : Problem {
             this += method.validateCheckedExceptionMethod(range, "@Binds methods may only throw unchecked exceptions. %s not allowed")
             this += method.validateMultipleScope(range, "@Binds methods cannot use more than one @Scope %s")
             this += method.validateMultipleQualifier(range, "@Binds methods may not use more than one @Qualifier %s")
+            this += method.validateVoidReturn(range, "@Binds methods must return a value (not void)")
         }
     }
 }

src/test/testData/binds/VoidReturn/KFailureComponent.kt

@@ -0,0 +1,13 @@
+import javax.inject.Inject
+import dagger.Module
+import dagger.Provides
+import dagger.Binds
+import assets.Car
+import assets.CarImpl
+
+@Module
+abstract class KVoidReturn {
+
+    @<error descr="@Binds methods must return a value (not void)">Binds</error>
+    abstract fun getCar(car: CarImpl)
+}

src/test/testData/binds/VoidReturn/VoidReturn.java

@@ -0,0 +1,11 @@
+import dagger.Module;
+import dagger.Binds;
+import assets.Car;
+import assets.CarImpl;
+
+@Module
+public abstract class VoidReturn {
+
+    @<error descr="@Binds methods must return a value (not void)">Binds</error>
+    public abstract void getCar(CarImpl car);
+}