adapter: fix merge skew in vars declaration #18004
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src/adapter/src/session/vars.rs
Outdated
| @@ -1193,7 +1193,7 @@ impl SystemVars { | |||
| /// Returns an iterator over the configuration parameters and their current | |||
| /// values on disk. | |||
| pub fn iter(&self) -> impl Iterator<Item = &dyn Var> { | |||
| let vars: [&dyn Var; 22] = [ | |||
| let vars: [&dyn Var; 23] = [ | |||
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If there is a way to not declare the type or use some type inference magic please feel free to force-push!
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@parker-timmerman any thoughts?
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Ideally we could do let vars: [&dyn Var; _] = ... and it would infer the length of the array, unfortunately that syntax is gated behind an unstable feature generic_arg_infer.
What we could do though is put &dyn Var on the first element i.e.
let vars = [
&self.config_has_synced_once as &dyn Var,
&self.max_aws_privatelink_connections,
...
];
which tells the compiler that we want to treat these as &dyn Var, and allows it to infer the length.
It doesn't look great, but it's the only way I know of to get the type inference here
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tbh I'm surprised the compiler didn't complain about the array being the wrong length 🤔
jk, just realized this was the result of a merge skew
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I really like that suggestion. This is not the first time this exact merge skew issue has happened, and it probably won't be the last.
Fixes a merge skew regression in some declaration of a fixed sized array.
Motivation
There was a merge skew with #17526 and #17966.
Tips for reviewer
N/A
Checklist
$T ⇔ Proto$Tmapping (possibly in a backwards-incompatible way) and therefore is tagged with aT-protolabel.