perf(ast): assume serde_json output is valid UTF8 string

[overlookmotel]

serde_json produces valid UTF8 output, so when converting serialized JSON to string, there's no need to check the output for UTF8 validity. Skipping that check is a speed-up.

Additionally, add a method to test the serializer without producing any output, and use it in conformance. This will hopefully speed up conformance a little.

[overlookmotel]

• perf(ast): assume serde_json output is valid UTF8 string #8928 👈 (View in Graphite)
• main

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[codspeed-hq]

CodSpeed Performance Report

Merging #8928 will create unknown performance changes

_{Comparing 02-06-perf_ast_assume_serde_json_output_is_valid_utf8_string (fcfc274) with main (b191390)}

Summary

🆕 33 new benchmarks

Benchmarks breakdown

	Benchmark	BASE	HEAD	Change
🆕	codegen[checker.ts]	N/A	24.9 ms	N/A
🆕	codegen_sourcemap[checker.ts]	N/A	68.3 ms	N/A
🆕	isolated-declarations[vue-id.ts]	N/A	723.7 ms	N/A
🆕	lexer[RadixUIAdoptionSection.jsx]	N/A	20.6 µs	N/A
🆕	lexer[antd.js]	N/A	22 ms	N/A
🆕	lexer[cal.com.tsx]	N/A	5.5 ms	N/A
🆕	lexer[checker.ts]	N/A	13.2 ms	N/A
🆕	lexer[pdf.mjs]	N/A	3.6 ms	N/A
🆕	linter[RadixUIAdoptionSection.jsx]	N/A	2.6 ms	N/A
🆕	linter[cal.com.tsx]	N/A	1.2 s	N/A
🆕	linter[checker.ts]	N/A	2.8 s	N/A
🆕	mangler[antd.js]	N/A	16.2 ms	N/A
🆕	mangler[react.development.js]	N/A	298 µs	N/A
🆕	mangler[typescript.js]	N/A	39.9 ms	N/A
🆕	minifier[antd.js]	N/A	158.6 ms	N/A
🆕	minifier[react.development.js]	N/A	1.6 ms	N/A
🆕	minifier[typescript.js]	N/A	272.2 ms	N/A
🆕	estree[checker.ts]	N/A	191 ms	N/A
🆕	parser[RadixUIAdoptionSection.jsx]	N/A	87.4 µs	N/A
🆕	parser[antd.js]	N/A	106.7 ms	N/A
...	...	...	...	...

ℹ️ Only the first 20 benchmarks are displayed. Go to the app to view all benchmarks.

[Boshen]

Merge activity

• Feb 8, 10:10 AM EST: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Feb 8, 10:10 AM EST: A user added this pull request to the Graphite merge queue.
• Feb 8, 10:25 AM EST: A user merged this pull request with the Graphite merge queue.