Convert Range instances to NS/CFRange structures when passed as argum…

…ent.

Closes #35.

bridgesupport.cpp

@@ -797,6 +797,27 @@ rb_vm_get_struct_fields(VALUE rval, VALUE *buf, rb_vm_bs_boxed_t *bs_boxed)
 	    buf[i] = RARRAY_AT(rval, i);
 	}
     }
+    else if (CLASS_OF(rval) == rb_cRange &&
+		(strcmp(bs_boxed->as.s->name, "NSRange") == 0 ||
+		    strcmp(bs_boxed->as.s->name, "CFRange") == 0)) {
+	VALUE b, e;
+	int exclusive;
+	rb_range_values(rval, &b, &e, &exclusive);
+	int begin = NUM2INT(b);
+	int end = NUM2INT(e);
+	if (begin < 0 || end < 0) {
+	    // We don't know what the max length of the range will be, so we
+	    // can't count backwards.
+	    rb_raise(rb_eArgError,
+		    "negative values are not allowed in ranges " \
+		    "that are converted to %s structures `%s'",
+		    bs_boxed->as.s->name,
+		    RSTRING_PTR(rb_inspect(rval)));
+	}
+	int length = exclusive ? end-1-begin : end-begin;
+	buf[0] = INT2NUM(begin);
+	buf[1] = INT2NUM(length);
+    }
     else {
 	if (!rb_obj_is_kind_of(rval, bs_boxed->klass)) {
 	    rb_raise(rb_eTypeError, 

range.c

@@ -691,10 +691,10 @@ rb_range_values(VALUE range, VALUE *begp, VALUE *endp, int *exclp)
     }
     else {
 	if (!rb_vm_respond_to(range, selBeg, false)) {
-	    return Qfalse;
+	    return 0;
 	}
 	if (!rb_vm_respond_to(range, selEnd, false)) {
-	    return Qfalse;
+	    return 0;
 	}
 	b = rb_vm_call(range, selBeg, 0, NULL);
 	e = rb_vm_call(range, selEnd, 0, NULL);

spec/macruby/language/objc_method_spec.rb

@@ -367,6 +367,22 @@ def o2.to_str; 'foo' end
     lambda { @o.methodAcceptingNSRect([[1, 2], [3, 4, 5]]) }.should raise_error(ArgumentError)
   end
 
+  it "accepting a Range as a structure type should receive a NSRange C structure" do
+    @o.methodAcceptingNSRange(0..41).should == 0
+    @o.methodAcceptingNSRange(1..42).should == 0
+    @o.methodAcceptingNSRange(0..42).should == 1
+    @o.methodAcceptingNSRange(0...42).should == 0
+    @o.methodAcceptingNSRange(1...42).should == 0
+    @o.methodAcceptingNSRange(0...43).should == 1
+
+    lambda { @o.methodAcceptingNSRange(-1..1) }.should raise_error(ArgumentError)
+    lambda { @o.methodAcceptingNSRange(1..-1) }.should raise_error(ArgumentError)
+    lambda { @o.methodAcceptingNSRange(-1..-1) }.should raise_error(ArgumentError)
+    lambda { @o.methodAcceptingNSRange(-1...1) }.should raise_error(ArgumentError)
+    lambda { @o.methodAcceptingNSRange(1...-1) }.should raise_error(ArgumentError)
+    lambda { @o.methodAcceptingNSRange(-1...-1) }.should raise_error(ArgumentError)
+  end
+
   it "accepting various C types should receive these types as expected" do
     @o.methodAcceptingInt(42, float:42, double:42, short:42, NSPoint:[42, 42],
                           NSRect:[42, 42, 42, 42], char:42).should == 1