Proposal to update ecma in terser

[JoviDeCroock]

Size changes are quite nice

[coveralls]

coverage: 99.536%. remained the same
when pulling eba3fa6 on save-bytes-with-ecma-2020
into 9c44db8 on main.

[github-actions]

📊 Tachometer Benchmark Results

Summary

duration

• create10k: unsure 🔍 -0% - +0% (-3.47ms - +3.14ms)
  ^{preact-local vs preact-main}
• filter-list: unsure 🔍 -0% - +0% (-0.02ms - +0.05ms)
  ^{preact-local vs preact-main}
• hydrate1k: unsure 🔍 -1% - +3% (-0.88ms - +2.42ms)
  ^{preact-local vs preact-main}
• many-updates: unsure 🔍 -3% - +4% (-0.52ms - +0.68ms)
  ^{preact-local vs preact-main}
• replace1k: unsure 🔍 -1% - +2% (-1.04ms - +1.61ms)
  ^{preact-local vs preact-main}
• text-update: unsure 🔍 -6% - +0% (-0.11ms - +0.01ms)
  ^{preact-local vs preact-main}
• todo: unsure 🔍 -2% - +1% (-0.61ms - +0.43ms)
  ^{preact-local vs preact-main}
• update10th1k: unsure 🔍 -3% - +4% (-0.98ms - +1.28ms)
  ^{preact-local vs preact-main}

usedJSHeapSize

• create10k: unsure 🔍 -0% - +0% (-0.02ms - +0.00ms)
  ^{preact-local vs preact-main}
• filter-list: unsure 🔍 -0% - +0% (-0.00ms - +0.00ms)
  ^{preact-local vs preact-main}
• hydrate1k: unsure 🔍 -4% - +9% (-0.25ms - +0.59ms)
  ^{preact-local vs preact-main}
• many-updates: unsure 🔍 -0% - +0% (-0.00ms - +0.00ms)
  ^{preact-local vs preact-main}
• replace1k: unsure 🔍 -1% - +1% (-0.03ms - +0.02ms)
  ^{preact-local vs preact-main}
• text-update: faster ✔ 0% - 4% (0.00ms - 0.04ms)
  ^{preact-local vs preact-main}
• todo: unsure 🔍 -0% - +0% (-0.00ms - +0.00ms)
  ^{preact-local vs preact-main}
• update10th1k: unsure 🔍 -0% - +0% (-0.01ms - +0.00ms)
  ^{preact-local vs preact-main}

Results

create10k

• Browser: chrome-headless
• Sample size: 50
• Built by: CI #5085

• Commit: aa6d6e5

duration

Version	Avg time	vs preact-local	vs preact-main
preact-local	973.39ms - 978.38ms	-	unsure 🔍 -0% - +0% -3.47ms - +3.14ms
preact-main	973.89ms - 978.22ms	unsure 🔍 -0% - +0% -3.14ms - +3.47ms	-

usedJSHeapSize

Version	Avg time	vs preact-local	vs preact-main
preact-local	19.03ms - 19.03ms	-	unsure 🔍 -0% - +0% -0.02ms - +0.00ms
preact-main	19.03ms - 19.06ms	unsure 🔍 -0% - +0% -0.00ms - +0.02ms	-

filter-list

• Browser: chrome-headless
• Sample size: 50
• Built by: CI #5085

• Commit: aa6d6e5

duration

Version	Avg time	vs preact-local	vs preact-main
preact-local	16.52ms - 16.58ms	-	unsure 🔍 -0% - +0% -0.02ms - +0.05ms
preact-main	16.52ms - 16.56ms	unsure 🔍 -0% - +0% -0.05ms - +0.02ms	-

usedJSHeapSize

Version	Avg time	vs preact-local	vs preact-main
preact-local	1.54ms - 1.54ms	-	unsure 🔍 -0% - +0% -0.00ms - +0.00ms
preact-main	1.54ms - 1.54ms	unsure 🔍 -0% - +0% -0.00ms - +0.00ms	-

hydrate1k

• Browser: chrome-headless
• Sample size: 90
• Built by: CI #5085

• Commit: aa6d6e5

duration

Version	Avg time	vs preact-local	vs preact-main
preact-local	72.38ms - 74.58ms	-	unsure 🔍 -1% - +3% -0.88ms - +2.42ms
preact-main	71.48ms - 73.93ms	unsure 🔍 -3% - +1% -2.42ms - +0.88ms	-

usedJSHeapSize

Version	Avg time	vs preact-local	vs preact-main
preact-local	6.32ms - 6.94ms	-	unsure 🔍 -4% - +9% -0.25ms - +0.59ms
preact-main	6.17ms - 6.75ms	unsure 🔍 -9% - +4% -0.59ms - +0.25ms	-

many-updates

• Browser: chrome-headless
• Sample size: 70
• Built by: CI #5085

• Commit: aa6d6e5

duration

Version	Avg time	vs preact-local	vs preact-main
preact-local	16.35ms - 17.00ms	-	unsure 🔍 -3% - +4% -0.52ms - +0.68ms
preact-main	16.09ms - 17.10ms	unsure 🔍 -4% - +3% -0.68ms - +0.52ms	-

usedJSHeapSize

Version	Avg time	vs preact-local	vs preact-main
preact-local	3.72ms - 3.72ms	-	unsure 🔍 -0% - +0% -0.00ms - +0.00ms
preact-main	3.72ms - 3.72ms	unsure 🔍 -0% - +0% -0.00ms - +0.00ms	-

replace1k

• Browser: chrome-headless
• Sample size: 90
• Built by: CI #5085

• Commit: aa6d6e5

duration

Version	Avg time	vs preact-local	vs preact-main
preact-local	71.56ms - 73.56ms	-	unsure 🔍 -1% - +2% -1.04ms - +1.61ms
preact-main	71.40ms - 73.15ms	unsure 🔍 -2% - +1% -1.61ms - +1.04ms	-

usedJSHeapSize

Version	Avg time	vs preact-local	vs preact-main
preact-local	3.02ms - 3.06ms	-	unsure 🔍 -1% - +1% -0.03ms - +0.02ms
preact-main	3.02ms - 3.06ms	unsure 🔍 -1% - +1% -0.02ms - +0.03ms	-

run-warmup-0

Version	Avg time	vs preact-local	vs preact-main
preact-local	26.50ms - 27.38ms	-	unsure 🔍 -3% - +2% -0.80ms - +0.42ms
preact-main	26.71ms - 27.55ms	unsure 🔍 -2% - +3% -0.42ms - +0.80ms	-

run-warmup-1

Version	Avg time	vs preact-local	vs preact-main
preact-local	34.41ms - 35.42ms	-	unsure 🔍 -0% - +3% -0.14ms - +1.15ms
preact-main	34.01ms - 34.81ms	unsure 🔍 -3% - +0% -1.15ms - +0.14ms	-

run-warmup-2

Version	Avg time	vs preact-local	vs preact-main
preact-local	35.05ms - 35.89ms	-	unsure 🔍 -0% - +3% -0.12ms - +0.98ms
preact-main	34.68ms - 35.40ms	unsure 🔍 -3% - +0% -0.98ms - +0.12ms	-

run-warmup-3

Version	Avg time	vs preact-local	vs preact-main
preact-local	27.76ms - 28.44ms	-	unsure 🔍 -2% - +1% -0.62ms - +0.31ms
preact-main	27.94ms - 28.58ms	unsure 🔍 -1% - +2% -0.31ms - +0.62ms	-

run-warmup-4

Version	Avg time	vs preact-local	vs preact-main
preact-local	24.99ms - 26.23ms	-	unsure 🔍 -3% - +4% -0.69ms - +0.96ms
preact-main	24.93ms - 26.02ms	unsure 🔍 -4% - +3% -0.96ms - +0.69ms	-

run-final

Version	Avg time	vs preact-local	vs preact-main
preact-local	22.90ms - 23.73ms	-	unsure 🔍 -4% - +1% -0.98ms - +0.24ms
preact-main	23.24ms - 24.14ms	unsure 🔍 -1% - +4% -0.24ms - +0.98ms	-

text-update

• Browser: chrome-headless
• Sample size: 230
• Built by: CI #5085

• Commit: aa6d6e5

duration

Version	Avg time	vs preact-local	vs preact-main
preact-local	1.85ms - 1.92ms	-	unsure 🔍 -6% - +0% -0.11ms - +0.01ms
preact-main	1.89ms - 1.98ms	unsure 🔍 -0% - +6% -0.01ms - +0.11ms	-

usedJSHeapSize

Version	Avg time	vs preact-local	vs preact-main
preact-local	0.97ms - 0.98ms	-	faster ✔ 0% - 4% 0.00ms - 0.04ms
preact-main	0.98ms - 1.01ms	slower ❌ 0% - 4% 0.00ms - 0.04ms	-

todo

• Browser: chrome-headless
• Sample size: 50
• Built by: CI #5085

• Commit: aa6d6e5

duration

Version	Avg time	vs preact-local	vs preact-main
preact-local	31.61ms - 32.44ms	-	unsure 🔍 -2% - +1% -0.61ms - +0.43ms
preact-main	31.81ms - 32.42ms	unsure 🔍 -1% - +2% -0.43ms - +0.61ms	-

usedJSHeapSize

Version	Avg time	vs preact-local	vs preact-main
preact-local	1.25ms - 1.25ms	-	unsure 🔍 -0% - +0% -0.00ms - +0.00ms
preact-main	1.25ms - 1.25ms	unsure 🔍 -0% - +0% -0.00ms - +0.00ms	-

update10th1k

• Browser: chrome-headless
• Sample size: 60
• Built by: CI #5085

• Commit: aa6d6e5

duration

Version	Avg time	vs preact-local	vs preact-main
preact-local	29.96ms - 31.54ms	-	unsure 🔍 -3% - +4% -0.98ms - +1.28ms
preact-main	29.79ms - 31.40ms	unsure 🔍 -4% - +3% -1.28ms - +0.98ms	-

usedJSHeapSize

Version	Avg time	vs preact-local	vs preact-main
preact-local	2.93ms - 2.94ms	-	unsure 🔍 -0% - +0% -0.01ms - +0.00ms
preact-main	2.93ms - 2.94ms	unsure 🔍 -0% - +0% -0.00ms - +0.01ms	-

_{tachometer-reporter-action v2 for CI}

[github-actions]

Size Change: -14 B (-0.03%)

Total Size: 47.5 kB

Filename	Size	Change
dist/preact.js	4.7 kB	-11 B (-0.23%)
dist/preact.mjs	4.72 kB	-3 B (-0.06%)

ℹ️ View Unchanged

Filename	Size
compat/dist/compat.js	3.9 kB
compat/dist/compat.mjs	3.82 kB
compat/dist/compat.umd.js	3.95 kB
debug/dist/debug.js	3.9 kB
debug/dist/debug.mjs	3.9 kB
debug/dist/debug.umd.js	3.98 kB
devtools/dist/devtools.js	263 B
devtools/dist/devtools.mjs	273 B
devtools/dist/devtools.umd.js	348 B
dist/preact.umd.js	4.78 kB
hooks/dist/hooks.js	1.55 kB
hooks/dist/hooks.mjs	1.58 kB
hooks/dist/hooks.umd.js	1.62 kB
jsx-runtime/dist/jsxRuntime.js	892 B
jsx-runtime/dist/jsxRuntime.mjs	861 B
jsx-runtime/dist/jsxRuntime.umd.js	966 B
test-utils/dist/testUtils.js	473 B
test-utils/dist/testUtils.mjs	473 B
test-utils/dist/testUtils.umd.js	555 B

_{compressed-size-action}

[rschristian]

Size benefits would likely be much greater if we made more adjustments to the source too, depending on perf characteristics. ES2020 means ES6 classes, which might save some bytes for BaseComponent, optional chaining in a few places, optional catch bindings (though perhaps terser already does this), etc. There'd be more opportunities besides the -14b I think, though that might mean dealing with Microbundle.

A 7 year jump in minimum browser versions probably isn't too unreasonable given the 6 year lifespan of X, though that is a big jump.

[JoviDeCroock]

Did a lot of the work in #4883 however it's really hard to make ESBuild work well with CJS/UMD, maybe I should try rolldown 😅

[rschristian]

I mean, we could just add a more minimal Rollup config? Speed is great, but if the newer tools can't produce output worth a damn, we can keep using older tools? That being said, Vitest is still pretty much unusable on my system so Microbundle might only seem acceptably slow to me.

I wouldn't be surprised if Microbundle is considerably slower than a more modern & purpose-built Rollup/Babel config too, maybe I'll take a look after work.