On Thu, 4 Jun 2026 17:53:52 GMT, Justin Lu <[email protected]> wrote:
>> Naoto Sato has updated the pull request incrementally with one additional
>> commit since the last revision:
>>
>> test mod
>
> src/java.base/share/classes/java/text/ListFormat.java line 687:
>
>> 685: var positions = new int[3];
>> 686: for (int i = 0; i < positions.length; i++) {
>> 687: var ph = "{" + i + "}";
>
> `ListFormat` uses `MessageFormat`, which means that any patterns taken by the
> former get passed to the latter.
>
> What would we expect to happen if `{3}` was passed as a pattern. Do we expect
> that to be printed out literally? Do we expect to reject it because it takes
> the form of a placeholder but exceeds the `0-2` value range?
>
> In the current form, depending on the number of elements, it could either be
> printed out literally, or it could be interpreted as a `MessageFormat`
> pattern. For example,
>
>
> String[] p = {
> "{3} {0}, {1}",
> "{0}, {1}",
> "{0}, and {1}",
> "",
> ""
> };
> var lf = ListFormat.getInstance(p);
> lf.format(List.of("a", "b", "c", "d")); // -> d a, b, c, and d
> lf.format(List.of("a", "b", "c")); // -> {3} a, b, and c
>
>
> I would not be opposed to rejecting any placeholders that are not in the form
> of only 0, 1, and 2. I am going to guess that no locales rely on
> {HARD_CODED_NUMBER} as being a part of their list patterns. What do you think?
Good point. I think rejecting is fine. In fact, I made it stricter as any curly
brace use other than 0/1/2 now throws an exception because MessageFormat has
its own parsing, which prevents "{foo}" from working as a literal.
-------------
PR Review Comment: https://git.openjdk.org/jdk/pull/31377#discussion_r3359553245
