From: citizen428@... Date: 2020-07-17T16:26:41+00:00 Subject: [ruby-core:99206] [Ruby master Bug#17034] Unexpected behavior in #max for beginless range Issue #17034 has been updated by citizen428 (Michael Kohl). File range-max-beginless.patch added citizen428 (Michael Kohl) wrote: > I think this is not ideal. Possible solutions: > > 1. Return `e` (`RANGE_END(range)` for beginless ranges or > 2. return a `RangeError` with a message like "cannot get the maximum of beginless range" (similar to `.min`). I had some time and looked into this. For inclusive integer ranges `r.end` will now be returned, no other behavior changes. Patch attached, but since the diff is very small I also opened a PR: https://github.com/ruby/ruby/pull/3328/ ---------------------------------------- Bug #17034: Unexpected behavior in #max for beginless range https://bugs.ruby-lang.org/issues/17034#change-86584 * Author: citizen428 (Michael Kohl) * Status: Open * Priority: Normal * ruby -v: 2.7.1p83 (2020-03-31 revision a0c7c23c9c) [x86_64-darwin19] * Backport: 2.5: UNKNOWN, 2.6: UNKNOWN, 2.7: UNKNOWN ---------------------------------------- When calling `max` on a beginless range, a non-intuitive error gets raised: ``` ruby r = ..9 r.max # ArgumentError: comparison of NilClass with 9 failed ``` There's a check for `NIL_P(RANGE_BEG(range))` but it's inside another check which is false for the example case above: ``` ruby if (rb_block_given_p() || (EXCL(range) && !nm) || argc) { if (NIL_P(RANGE_BEG(range))) { rb_raise(rb_eRangeError, "cannot get the maximum of beginless range with custom comparison method"); } return rb_call_super(argc, argv); } ``` The first part of the condition is false since there is no block, and even though I'm not sure what `EXCL` does the second part of the condition will be false due to `!nm` (`nm` will be true because of `FIXNUM_P(e)`). So I think the error gets raised here: ``` ruby int c = OPTIMIZED_CMP(b, e, cmp_opt); ``` I think this is not ideal. Possible solutions: 1. Return `e` (`RANGE_END(range)` for beginless ranges or 2. return a `RangeError` with a message like "cannot get the maximum of beginless range" (similar to `.min`). Happy to provide a patch if people want this changed and can agree on what the new behavior should be. ---Files-------------------------------- range-max-beginless.patch (1.26 KB) -- https://bugs.ruby-lang.org/ Unsubscribe: