Allow custom parameter resolution for table tests

src/com/googlecode/yatspec/junit/DecoratingFrameworkMethod.java

@@ -1,17 +1,14 @@
 package com.googlecode.yatspec.junit;
 
-import com.googlecode.totallylazy.Sequence;
 import com.googlecode.yatspec.rendering.ScenarioNameRendererFactory;
 import com.googlecode.yatspec.state.ScenarioName;
 import org.junit.runners.model.FrameworkMethod;
 
-import java.lang.reflect.Array;
-import java.util.Arrays;
-
-import static com.googlecode.totallylazy.Sequences.sequence;
+import static com.googlecode.yatspec.junit.ParameterResolverFactory.parameterResolver;
 import static java.util.Arrays.asList;
 
 public class DecoratingFrameworkMethod extends FrameworkMethod {
+
     private final Row row;
 
     public DecoratingFrameworkMethod(FrameworkMethod method, Row row) {
@@ -20,39 +17,9 @@ public DecoratingFrameworkMethod(FrameworkMethod method, Row row) {
     }
 
     @Override
-    public Object invokeExplosively(Object target, Object... params) throws Throwable {
-        final Object[] suppliedParams = row.value();
-        final Class<?>[] requiredParams = getMethod().getParameterTypes();
-
-        if (requiresNoVarArgs(requiredParams)) {
-            return super.invokeExplosively(target, suppliedParams);
-        }
-
-        if (isMissingRequiredArguments(suppliedParams, requiredParams)) {
-            throw new IllegalArgumentException("Missing parameters.");
-        }
-
-        final Sequence<Object> preparedParams = sequence(suppliedParams).take(Math.min(requiredParams.length - 1, suppliedParams.length)).append(getVarargsFrom(suppliedParams, requiredParams));
-        return super.invokeExplosively(target, preparedParams.toArray());
-    }
-
-    private boolean requiresNoVarArgs(Class<?>[] methodParams) {
-        return !methodParams[methodParams.length - 1].isArray();
-    }
-
-    private boolean isMissingRequiredArguments(Object[] input, Class<?>[] expected) {
-        return input.length < expected.length - 1;
-    }
-
-    private boolean hasVarArgsSupplied(Object[] input, Class<?>[] expected) {
-        return input.length >= expected.length;
-    }
-
-    private Object getVarargsFrom(Object[] suppliedParams, Class<?>[] requiredParams) {
-        if (hasVarArgsSupplied(suppliedParams, requiredParams)) {
-            return Arrays.copyOfRange(suppliedParams, requiredParams.length - 1, suppliedParams.length);
-        }
-        return Array.newInstance(requiredParams[requiredParams.length - 1].getComponentType(), 0);
+    public Object invokeExplosively(Object test, Object... ignored) throws Throwable {
+        Object[] testMethodParameters = parameterResolver().resolveParameters(row, test.getClass(), getMethod());
+        return super.invokeExplosively(test, testMethodParameters);
     }
 
     @Override
@@ -80,4 +47,4 @@ public int hashCode() {
         result = 31 * result + row.hashCode();
         return result;
     }
-}
+}

src/com/googlecode/yatspec/junit/ParameterResolver.java

@@ -0,0 +1,7 @@
+package com.googlecode.yatspec.junit;
+
+import java.lang.reflect.Method;
+
+public interface ParameterResolver {
+    Object[] resolveParameters(Row row, Class<?> testClass, Method testMethod) throws Exception;
+}

src/com/googlecode/yatspec/junit/ParameterResolverFactory.java

@@ -0,0 +1,22 @@
+package com.googlecode.yatspec.junit;
+
+import static com.googlecode.yatspec.Creator.create;
+import static java.lang.Class.forName;
+import static java.lang.System.getProperty;
+
+public class ParameterResolverFactory {
+
+    public static final String PARAMETER_RESOLVER = "yatspec.parameter.resolver";
+
+    public static void setParameterResolver(Class<? extends ParameterResolver> aClass) {
+        System.setProperty(PARAMETER_RESOLVER, aClass.getName());
+    }
+
+    public static ParameterResolver parameterResolver() {
+        try {
+            return create(forName(getProperty(PARAMETER_RESOLVER, VarargsParameterResolver.class.getName())));
+        } catch (Exception e) {
+            return new VarargsParameterResolver();
+        }
+    }
+}

src/com/googlecode/yatspec/junit/VarargsParameterResolver.java

@@ -0,0 +1,45 @@
+package com.googlecode.yatspec.junit;
+
+import java.lang.reflect.Array;
+import java.lang.reflect.Method;
+import java.util.Arrays;
+
+import static com.googlecode.totallylazy.Sequences.sequence;
+
+public class VarargsParameterResolver implements ParameterResolver {
+
+    @Override
+    public Object[] resolveParameters(Row row, Class<?> testClass, Method testMethod) throws Exception {
+        final Object[] suppliedParams = row.value();
+        final Class<?>[] requiredParams = testMethod.getParameterTypes();
+
+        if (requiresNoVarArgs(requiredParams)) {
+            return suppliedParams;
+        }
+
+        if (isMissingRequiredArguments(suppliedParams, requiredParams)) {
+            throw new IllegalArgumentException("Missing parameters.");
+        }
+
+        return sequence(suppliedParams).take(Math.min(requiredParams.length - 1, suppliedParams.length)).append(getVarargsFrom(suppliedParams, requiredParams)).toArray();
+    }
+
+    private boolean requiresNoVarArgs(Class<?>[] methodParams) {
+        return !methodParams[methodParams.length - 1].isArray();
+    }
+
+    private boolean isMissingRequiredArguments(Object[] input, Class<?>[] expected) {
+        return input.length < expected.length - 1;
+    }
+
+    private boolean hasVarArgsSupplied(Object[] input, Class<?>[] expected) {
+        return input.length >= expected.length;
+    }
+
+    private Object getVarargsFrom(Object[] suppliedParams, Class<?>[] requiredParams) {
+        if (hasVarArgsSupplied(suppliedParams, requiredParams)) {
+            return Arrays.copyOfRange(suppliedParams, requiredParams.length - 1, suppliedParams.length);
+        }
+        return Array.newInstance(requiredParams[requiredParams.length - 1].getComponentType(), 0);
+    }
+}