Fix coercion of arrays in Kernel#Array and Array#product.

Fixes #1961.
Fixes #1962.

Author: headius

core/src/main/java/org/jruby/RubyArray.java

@@ -3542,7 +3542,7 @@ public IRubyObject product19(ThreadContext context, IRubyObject[] args, Block bl
         int counters[] = new int[n];
 
         arrays[0] = this;
-        for (int i = 1; i < n; i++) arrays[i] = args[i - 1].convertToArray();
+        for (int i = 1; i < n; i++) arrays[i] = TypeConverter.to_ary(context, args[i - 1]);
 
         int resultLen = 1;
         for (int i = 0; i < n; i++) {

core/src/main/java/org/jruby/RubyKernel.java

@@ -375,11 +375,17 @@ public static IRubyObject abort(ThreadContext context, IRubyObject recv, IRubyOb
         return runtime.getNil(); // not reached
     }
 
-    @JRubyMethod(name = "Array", required = 1, module = true, visibility = PRIVATE)
-    public static IRubyObject new_array(ThreadContext context, IRubyObject recv, IRubyObject object) {
+    @JRubyMethod(name = "Array", required = 1, module = true, visibility = PRIVATE, compat = RUBY1_8)
+    public static IRubyObject new_array18(ThreadContext context, IRubyObject recv, IRubyObject object) {
         return Helpers.asArray18(context, object);
     }
 
+    // MRI: rb_f_array
+    @JRubyMethod(name = "Array", required = 1, module = true, visibility = PRIVATE, compat = RUBY1_9)
+    public static IRubyObject new_array(ThreadContext context, IRubyObject recv, IRubyObject object) {
+        return TypeConverter.rb_Array(context, object);
+    }
+
     @JRubyMethod(name = "Complex", module = true, visibility = PRIVATE, compat = RUBY1_9)
     public static IRubyObject new_complex(ThreadContext context, IRubyObject recv) {
         return Helpers.invoke(context, context.runtime.getComplex(), "convert");

core/src/main/java/org/jruby/runtime/Helpers.java

@@ -1852,16 +1852,7 @@ public static RubyArray asArray18(ThreadContext context, IRubyObject value) {
     // mri: rb_Array
     // FIXME: Replace arrayValue/asArray18 with this on 9k (currently dead -- respond_to? logic broken further down the line -- fix that first)
     public static RubyArray asArray(ThreadContext context, IRubyObject value) {
-        RubyClass array = context.runtime.getArray();
-        IRubyObject tmp = TypeConverter.convertToTypeWithCheck19(value, array, "to_ary");
-        
-        if (tmp.isNil()) {
-            tmp = TypeConverter.convertToTypeWithCheck19(value, array, "to_a");
-
-            if (tmp.isNil()) return context.runtime.newEmptyArray();
-        }
-        
-        return (RubyArray) tmp; // converters will guarantee it is RubyArray or raise.
+        return TypeConverter.rb_Array(context, value);
     }
 
     public static IRubyObject aryToAry(IRubyObject value) {

core/src/main/java/org/jruby/util/TypeConverter.java

@@ -27,6 +27,7 @@
 package org.jruby.util;
 
 import org.jruby.Ruby;
+import org.jruby.RubyArray;
 import org.jruby.RubyBignum;
 import org.jruby.RubyBoolean;
 import org.jruby.RubyClass;
@@ -283,6 +284,11 @@ public static IRubyObject checkStringType(Ruby runtime, IRubyObject obj) {
         return TypeConverter.convertToTypeWithCheck(obj, runtime.getHash(), "to_str");
     }
 
+    // MRI: rb_check_array_type
+    public static IRubyObject checkArrayType(IRubyObject self) {
+        return TypeConverter.convertToTypeWithCheck19(self, self.getRuntime().getArray(), "to_ary");
+    }
+
     public static IRubyObject handleUncoercibleObject(boolean raise, IRubyObject obj, RubyClass target) throws RaiseException {
         if (raise) throw obj.getRuntime().newTypeError("can't convert " + typeAsString(obj) + " into " + target);
 
@@ -330,6 +336,24 @@ public static IRubyObject convertToInteger(ThreadContext context, IRubyObject va
         return tmp;
     }
 
+    // MRI: rb_Array
+    public static RubyArray rb_Array(ThreadContext context, IRubyObject val) {
+        IRubyObject tmp = checkArrayType(val);
+
+        if (tmp.isNil()) {
+            tmp = convertToTypeWithCheck19(val, context.runtime.getArray(), "to_a");
+            if (tmp.isNil()) {
+                return context.runtime.newArray(val);
+            }
+        }
+        return (RubyArray)tmp;
+    }
+
+    // MRI: to_ary
+    public static RubyArray to_ary(ThreadContext context, IRubyObject ary) {
+        return (RubyArray)convertToType19(ary, context.runtime.getArray(), "to_ary");
+    }
+
     private static void raiseIntegerBaseError(ThreadContext context) {
         throw context.runtime.newArgumentError("base specified for non string value");
     }