perf: reduce allocations in MediaType::from_specifier
#7
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| // slower here, so continue to use to_lowercase() | ||
| let lowercase_str = ext.to_lowercase(); | ||
| match lowercase_str.as_str() { | ||
| "ts" => map_typescript_like(path, Self::TypeScript, Self::Dts), |
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Might be neat to have a macro that expands "ts" to "ts" | "TS" | "Ts" | "tS"... seems to reduce 268ns -> 220ns
Edit: or maybe something like this might be best:
case_insensitive_match!(ext {
"ts" => map_typescript_like(path, Self::TypeScript, Self::Dts),
"mts" => map_typescript_like(path, Self::Mts, Self::Dmts),
...etc...
})...then that could be a proc macro that generates the most optimal matching strategy.
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Maybe @nathanwhit could tackle that?
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Maybe we could use https://doc.rust-lang.org/std/string/struct.String.html#method.eq_ignore_ascii_case instead? I think we could just create a macro that checks string length and uses that method for each case, and the compiler would be reasonably good at optimizing it.
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I tried that and it was slower than the match in this case for some reason (I think 40ns slower). It was faster for tsbuildinfo somewhere else in this file. Edit: Didn't try matching on string length though
This is used a lot in the node resolution.