Software / code / prosody
Changeset
10592:9918b4b0cd58
util.array: Fix equality metamethod in Lua 5.3
Lua 5.2 only used the __eq metamethod if both operands have the same
__eq, but Lua 5.3 will pick one from either operands that has one as
long as both are tables.
This results in array() == {} and all sorts of odd behavior, including
array() == util.json.null.
<MattJ> I think [array() == {}] should have the same semantics as {} == {}
| author | Kim Alvefur <zash@zash.se> |
|---|---|
| date | Wed, 15 Jan 2020 21:08:01 +0100 |
| parents | 10591:d78c5c9b0cf6 |
| children | 10593:079b31c8dbf2 |
| files | util/array.lua |
| diffstat | 1 files changed, 5 insertions(+), 0 deletions(-) [+] |
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--- a/util/array.lua Wed Jan 15 21:14:06 2020 +0100 +++ b/util/array.lua Wed Jan 15 21:08:01 2020 +0100 @@ -10,6 +10,7 @@ = table.insert, table.sort, table.remove, table.concat; local setmetatable = setmetatable; +local getmetatable = getmetatable; local math_random = math.random; local math_floor = math.floor; local pairs, ipairs = pairs, ipairs; @@ -40,6 +41,10 @@ end function array_mt.__eq(a, b) + if getmetatable(a) ~= array_mt or getmetatable(b) ~= array_mt then + -- Lua 5.3+ calls this if both operands are tables, even if metatables differ + return false; + end if #a == #b then for i = 1, #a do if a[i] ~= b[i] then
