Bug #20229: Empty keyword splat in array not removed in ARGSPUSH case

• Status: Closed
• Assignee: -
• Target version: -
• Backport: 3.0: UNKNOWN, 3.1: UNKNOWN, 3.2: UNKNOWN, 3.3: UNKNOWN

[jeremyevans0 (Jeremy Evans)]

For the following code:

a = []
kw = {}
[*a, **kw]

Ruby 2.0-3.3 return [{}], when the desired result (since 2.7) is [].

I discovered this while working on an optimization for the ARGSCAT case, where [*a, 1, **kw] allocates two arrays instead of a single array. My optimization fixes that by adding a pushtoarraykwsplat instruction as a replacement for newarraykwsplat. I've used pushtoarraykwsplat in the ARGSPUSH case to fix this bug.

My pull request for the bug fix and optimization: https://github.com/ruby/ruby/pull/9766

[jeremyevans0 (Jeremy Evans)]

• Related to Bug #20180: Inconsistent evaluation of `**{}` depending on position in array added

[jeremyevans0 (Jeremy Evans)]

I found that this bug was actually reported earlier in #20180, which I already have submitted a pull request to fix. I think we should use the approach in this pull request to fix this issue in master, as it is more efficient. We could backport the fix in #20180 to Ruby 3.1-3.3.

[jeremyevans0 (Jeremy Evans)]

• Status changed from Open to Closed

Committed as 77c1233f79a0f96a081b70da533fbbde4f3037fa