Fix index in error message of `Struct#[]`
Before this patch:
$ bin/mruby -e 'Struct.new(:a,:b).new[-3]'
#=> offset -1 too small for struct(size:2) (IndexError)
After this patch (same as Ruby):
$ bin/mruby -e 'Struct.new(:a,:b).new[-3]'
#=> offset -3 too small for struct(size:2) (IndexError)
MODIFY
mrbgems/mruby-struct/src/struct.c
mrbgems/mruby-struct/src/struct.c
@@ -385,16 +385,17 @@ struct_aref_sym(mrb_state *mrb, mrb_value obj, mrb_sym id)
static mrb_value
struct_aref_int(mrb_state *mrb, mrb_value s, mrb_int i)
{
- if (i < 0) i = RSTRUCT_LEN(s) + i;
- if (i < 0)
+ mrb_int idx = i < 0 ? RSTRUCT_LEN(s) + i : i;
+
+ if (idx < 0)
mrb_raisef(mrb, E_INDEX_ERROR,
"offset %S too small for struct(size:%S)",
mrb_fixnum_value(i), mrb_fixnum_value(RSTRUCT_LEN(s)));
- if (RSTRUCT_LEN(s) <= i)
+ if (RSTRUCT_LEN(s) <= idx)
mrb_raisef(mrb, E_INDEX_ERROR,
"offset %S too large for struct(size:%S)",
mrb_fixnum_value(i), mrb_fixnum_value(RSTRUCT_LEN(s)));
- return RSTRUCT_PTR(s)[i];
+ return RSTRUCT_PTR(s)[idx];
}
/* 15.2.18.4.2 */

Fix index in error message of `Struct#[]`

Before this patch:

  $ bin/mruby -e 'Struct.new(:a,:b).new[-3]'
  #=> offset -1 too small for struct(size:2) (IndexError)

After this patch (same as Ruby):

  $ bin/mruby -e 'Struct.new(:a,:b).new[-3]'
  #=> offset -3 too small for struct(size:2) (IndexError)