nushell/crates/nu-command
JT d00038eb4b
Reuse the cached parse results of parsed files (#8949)
# Description

This does a lookup in the cache of parsed files to see if a span can be
found for a file that was previously loaded with the same contents, then
uses that span to find the parsed block for that file. The end result
should, in theory, be identical but doesn't require any reparsing or
creating new blocks/new definitions that aren't needed.

This drops the sg.nu benchmark from:
```
╭───┬───────────────────╮
│ 0 │ 280ms 606µs 208ns │
│ 1 │ 282ms 654µs 416ns │
│ 2 │ 252ms 640µs 541ns │
│ 3 │  250ms 940µs 41ns │
│ 4 │ 241ms 216µs 375ns │
│ 5 │ 257ms 310µs 583ns │
│ 6 │ 196ms 739µs 416ns │
╰───┴───────────────────╯
```

to:
```
╭───┬───────────────────╮
│ 0 │ 118ms 698µs 125ns │
│ 1 │       121ms 327µs │
│ 2 │ 121ms 873µs 500ns │
│ 3 │  124ms 94µs 708ns │
│ 4 │ 113ms 733µs 291ns │
│ 5 │ 108ms 663µs 125ns │
│ 6 │  63ms 482µs 625ns │
╰───┴───────────────────╯
```

I was hoping to also see some startup time improvements, but I didn't
notice much there.

# User-Facing Changes
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# Tests + Formatting
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2023-04-22 07:00:33 +12:00
..
assets refactor html module (#5246) 2022-04-20 08:50:14 -05:00
src allow find command to look in specified columns only (#8937) 2023-04-20 08:13:12 -05:00
tests Reuse the cached parse results of parsed files (#8949) 2023-04-22 07:00:33 +12:00
Cargo.toml Upgrade open crate to fix WSL bug (#8905) 2023-04-16 22:05:40 -07:00
LICENSE Fix rest of license year ranges (#8727) 2023-04-04 09:03:29 +12:00