fix case where keyed children would get removed

[JoviDeCroock]

Fixes #3766

When we have a fragment the DOM needs to dig deeper to find the matching elements, what happens is that we remove 1 element which means when we always skip by 2 we can't find any elements anymore, I know we have went back and forth on removing/not-removing this quite a bit now but this is a really valid case imo.

We can still opt not to do this for unkeyed elements if we find the byte-offset worth which might be a bit expensive as we would have to carry the fact that there's a parent to the Fragment that has a key

[github-actions]

📊 Tachometer Benchmark Results

Summary

duration

• 02_replace1k: unsure 🔍 -6% - +24% (-5.24ms - +22.50ms)
  ^{preact-local vs preact-master}
• 03_update10th1k_x16: unsure 🔍 -5% - +1% (-2.54ms - +0.79ms)
  ^{preact-local vs preact-master}
• 07_create10k: slower ❌ 0% - 3% (1.28ms - 55.24ms)
  ^{preact-local vs preact-master}
• filter_list: unsure 🔍 -2% - +2% (-0.43ms - +0.40ms)
  ^{preact-local vs preact-master}
• hydrate1k: unsure 🔍 -3% - +4% (-5.69ms - +7.63ms)
  ^{preact-local vs preact-master}
• many_updates: unsure 🔍 -3% - +5% (-1.06ms - +1.78ms)
  ^{preact-local vs preact-master}
• text_update: unsure 🔍 -2% - +1% (-0.06ms - +0.03ms)
  ^{preact-local vs preact-master}
• todo: unsure 🔍 -1% - +0% (-0.62ms - +0.05ms)
  ^{preact-local vs preact-master}

usedJSHeapSize

• 02_replace1k: unsure 🔍 -12% - +4% (-0.56ms - +0.22ms)
  ^{preact-local vs preact-master}
• 03_update10th1k_x16: unsure 🔍 -0% - +0% (-0.00ms - +0.01ms)
  ^{preact-local vs preact-master}
• 07_create10k: unsure 🔍 -0% - +0% (-0.00ms - +0.00ms)
  ^{preact-local vs preact-master}
• filter_list: unsure 🔍 -0% - +0% (-0.00ms - +0.00ms)
  ^{preact-local vs preact-master}
• hydrate1k: unsure 🔍 -4% - +3% (-0.62ms - +0.53ms)
  ^{preact-local vs preact-master}
• many_updates: unsure 🔍 -0% - +0% (-0.00ms - +0.01ms)
  ^{preact-local vs preact-master}
• text_update: unsure 🔍 -0% - +0% (-0.00ms - +0.00ms)
  ^{preact-local vs preact-master}
• todo: unsure 🔍 -0% - +0% (-0.00ms - +0.00ms)
  ^{preact-local vs preact-master}

Results

02_replace1k

• Browser: chrome-headless 106.0.5249.119
• Sample size: 70
• Built by: Benchmarks #924

• Commit: deb2646

duration

Version	Avg time	vs preact-master	vs preact-local	vs preact-hooks
preact-master	87.02ms - 107.94ms	-	unsure 🔍 -21% - +4% -22.50ms - +5.24ms	unsure 🔍 -12% - +23% -10.29ms - +20.89ms
preact-local	97.00ms - 115.21ms	unsure 🔍 -6% - +24% -5.24ms - +22.50ms	-	unsure 🔍 -2% - +33% -0.78ms - +28.64ms
preact-hooks	80.62ms - 103.74ms	unsure 🔍 -21% - +10% -20.89ms - +10.29ms	unsure 🔍 -26% - +0% -28.64ms - +0.78ms	-

usedJSHeapSize

Version	Avg time	vs preact-master	vs preact-local	vs preact-hooks
preact-master	4.44ms - 4.98ms	-	unsure 🔍 -5% - +12% -0.22ms - +0.56ms	faster ✔ 7% - 22% 0.36ms - 1.26ms
preact-local	4.27ms - 4.81ms	unsure 🔍 -12% - +4% -0.56ms - +0.22ms	-	faster ✔ 11% - 25% 0.53ms - 1.43ms
preact-hooks	5.16ms - 5.88ms	slower ❌ 7% - 27% 0.36ms - 1.26ms	slower ❌ 11% - 32% 0.53ms - 1.43ms	-

run-warmup-0

Version	Avg time	vs preact-master	vs preact-local	vs preact-hooks
preact-master	1.01ms - 1.06ms	-	unsure 🔍 -3% - +3% -0.03ms - +0.03ms	unsure 🔍 -5% - +1% -0.05ms - +0.01ms
preact-local	1.02ms - 1.05ms	unsure 🔍 -3% - +3% -0.03ms - +0.03ms	-	unsure 🔍 -5% - +1% -0.05ms - +0.01ms
preact-hooks	1.03ms - 1.08ms	unsure 🔍 -1% - +5% -0.01ms - +0.05ms	unsure 🔍 -1% - +5% -0.01ms - +0.05ms	-

run-warmup-1

Version	Avg time	vs preact-master	vs preact-local	vs preact-hooks
preact-master	0.82ms - 1.23ms	-	unsure 🔍 -35% - +19% -0.40ms - +0.23ms	faster ✔ 67% - 80% 2.29ms - 3.40ms
preact-local	0.88ms - 1.35ms	unsure 🔍 -23% - +40% -0.23ms - +0.40ms	-	faster ✔ 64% - 78% 2.19ms - 3.33ms
preact-hooks	3.35ms - 4.39ms	slower ❌ 186% - 370% 2.29ms - 3.40ms	slower ❌ 161% - 336% 2.19ms - 3.33ms	-

run-warmup-2

Version	Avg time	vs preact-master	vs preact-local	vs preact-hooks
preact-master	0.41ms - 0.52ms	-	unsure 🔍 -7% - +22% -0.03ms - +0.10ms	unsure 🔍 -2% - +28% -0.01ms - +0.11ms
preact-local	0.41ms - 0.45ms	unsure 🔍 -20% - +5% -0.10ms - +0.03ms	-	unsure 🔍 -1% - +11% -0.01ms - +0.05ms
preact-hooks	0.40ms - 0.43ms	unsure 🔍 -23% - +0% -0.11ms - +0.01ms	unsure 🔍 -10% - +1% -0.05ms - +0.01ms	-

run-warmup-3

Version	Avg time	vs preact-master	vs preact-local	vs preact-hooks
preact-master	0.35ms - 0.75ms	-	unsure 🔍 -39% - +68% -0.18ms - +0.32ms	unsure 🔍 -47% - +48% -0.25ms - +0.26ms
preact-local	0.34ms - 0.63ms	unsure 🔍 -54% - +28% -0.32ms - +0.18ms	-	unsure 🔍 -50% - +25% -0.29ms - +0.15ms
preact-hooks	0.38ms - 0.71ms	unsure 🔍 -47% - +46% -0.26ms - +0.25ms	unsure 🔍 -35% - +62% -0.15ms - +0.29ms	-

run-warmup-4

Version	Avg time	vs preact-master	vs preact-local	vs preact-hooks
preact-master	0.30ms - 0.36ms	-	unsure 🔍 -16% - +11% -0.06ms - +0.04ms	faster ✔ 22% - 39% 0.10ms - 0.19ms
preact-local	0.30ms - 0.37ms	unsure 🔍 -12% - +17% -0.04ms - +0.06ms	-	faster ✔ 20% - 38% 0.09ms - 0.18ms
preact-hooks	0.44ms - 0.50ms	slower ❌ 27% - 60% 0.10ms - 0.19ms	slower ❌ 22% - 58% 0.09ms - 0.18ms	-

run-final

Version	Avg time	vs preact-master	vs preact-local	vs preact-hooks
preact-master	0.28ms - 0.33ms	-	unsure 🔍 -23% - +4% -0.08ms - +0.02ms	faster ✔ 17% - 32% 0.06ms - 0.13ms
preact-local	0.30ms - 0.38ms	unsure 🔍 -6% - +26% -0.02ms - +0.08ms	-	faster ✔ 5% - 28% 0.02ms - 0.12ms
preact-hooks	0.38ms - 0.43ms	slower ❌ 19% - 45% 0.06ms - 0.13ms	slower ❌ 3% - 37% 0.02ms - 0.12ms	-

03_update10th1k_x16

• Browser: chrome-headless 106.0.5249.119
• Sample size: 80
• Built by: Benchmarks #924

• Commit: deb2646

duration

Version	Avg time	vs preact-master	vs preact-local	vs preact-hooks
preact-master	52.64ms - 55.10ms	-	unsure 🔍 -2% - +5% -0.79ms - +2.54ms	unsure 🔍 -2% - +3% -1.33ms - +1.81ms
preact-local	51.87ms - 54.12ms	unsure 🔍 -5% - +1% -2.54ms - +0.79ms	-	unsure 🔍 -4% - +2% -2.13ms - +0.85ms
preact-hooks	52.65ms - 54.61ms	unsure 🔍 -3% - +2% -1.81ms - +1.33ms	unsure 🔍 -2% - +4% -0.85ms - +2.13ms	-

usedJSHeapSize

Version	Avg time	vs preact-master	vs preact-local	vs preact-hooks
preact-master	3.78ms - 3.79ms	-	unsure 🔍 -0% - +0% -0.01ms - +0.00ms	faster ✔ 10% - 10% 0.40ms - 0.41ms
preact-local	3.78ms - 3.79ms	unsure 🔍 -0% - +0% -0.00ms - +0.01ms	-	faster ✔ 10% - 10% 0.40ms - 0.41ms
preact-hooks	4.19ms - 4.19ms	slower ❌ 11% - 11% 0.40ms - 0.41ms	slower ❌ 11% - 11% 0.40ms - 0.41ms	-

07_create10k

• Browser: chrome-headless 106.0.5249.119
• Sample size: 60
• Built by: Benchmarks #924

• Commit: deb2646

duration

Version	Avg time	vs preact-master	vs preact-local	vs preact-hooks
preact-master	1594.34ms - 1630.06ms	-	faster ✔ 0% - 3% 1.28ms - 55.24ms	faster ✔ 2% - 5% 35.47ms - 87.35ms
preact-local	1620.23ms - 1660.68ms	slower ❌ 0% - 3% 1.28ms - 55.24ms	-	faster ✔ 0% - 4% 5.53ms - 60.77ms
preact-hooks	1654.80ms - 1692.42ms	slower ❌ 2% - 5% 35.47ms - 87.35ms	slower ❌ 0% - 4% 5.53ms - 60.77ms	-

usedJSHeapSize

Version	Avg time	vs preact-master	vs preact-local	vs preact-hooks
preact-master	25.84ms - 25.84ms	-	unsure 🔍 -0% - +0% -0.00ms - +0.00ms	faster ✔ 9% - 9% 2.55ms - 2.55ms
preact-local	25.84ms - 25.84ms	unsure 🔍 -0% - +0% -0.00ms - +0.00ms	-	faster ✔ 9% - 9% 2.55ms - 2.55ms
preact-hooks	28.39ms - 28.39ms	slower ❌ 10% - 10% 2.55ms - 2.55ms	slower ❌ 10% - 10% 2.55ms - 2.55ms	-

filter_list

• Browser: chrome-headless 106.0.5249.119
• Sample size: 50
• Built by: Benchmarks #924

• Commit: deb2646

duration

Version	Avg time	vs preact-master	vs preact-local	vs preact-hooks
preact-master	22.47ms - 23.05ms	-	unsure 🔍 -2% - +2% -0.40ms - +0.43ms	slower ❌ 0% - 3% 0.03ms - 0.77ms
preact-local	22.45ms - 23.03ms	unsure 🔍 -2% - +2% -0.43ms - +0.40ms	-	slower ❌ 0% - 3% 0.02ms - 0.75ms
preact-hooks	22.14ms - 22.58ms	faster ✔ 0% - 3% 0.03ms - 0.77ms	faster ✔ 0% - 3% 0.02ms - 0.75ms	-

usedJSHeapSize

Version	Avg time	vs preact-master	vs preact-local	vs preact-hooks
preact-master	1.93ms - 1.93ms	-	unsure 🔍 -0% - +0% -0.00ms - +0.00ms	faster ✔ 11% - 11% 0.24ms - 0.24ms
preact-local	1.93ms - 1.93ms	unsure 🔍 -0% - +0% -0.00ms - +0.00ms	-	faster ✔ 11% - 11% 0.24ms - 0.24ms
preact-hooks	2.16ms - 2.16ms	slower ❌ 12% - 12% 0.24ms - 0.24ms	slower ❌ 12% - 12% 0.24ms - 0.24ms	-

hydrate1k

• Browser: chrome-headless 106.0.5249.119
• Sample size: 70
• Built by: Benchmarks #924

• Commit: deb2646

duration

Version	Avg time	vs preact-master	vs preact-local	vs preact-hooks
preact-master	196.46ms - 206.21ms	-	unsure 🔍 -4% - +3% -7.63ms - +5.69ms	unsure 🔍 -6% - +1% -11.61ms - +1.66ms
preact-local	197.76ms - 206.85ms	unsure 🔍 -3% - +4% -5.69ms - +7.63ms	-	unsure 🔍 -5% - +1% -10.40ms - +2.39ms
preact-hooks	201.81ms - 210.81ms	unsure 🔍 -1% - +6% -1.66ms - +11.61ms	unsure 🔍 -1% - +5% -2.39ms - +10.40ms	-

usedJSHeapSize

Version	Avg time	vs preact-master	vs preact-local	vs preact-hooks
preact-master	15.15ms - 15.93ms	-	unsure 🔍 -3% - +4% -0.53ms - +0.62ms	unsure 🔍 -3% - +6% -0.39ms - +0.85ms
preact-local	15.08ms - 15.91ms	unsure 🔍 -4% - +3% -0.62ms - +0.53ms	-	unsure 🔍 -3% - +5% -0.46ms - +0.82ms
preact-hooks	14.83ms - 15.79ms	unsure 🔍 -5% - +3% -0.85ms - +0.39ms	unsure 🔍 -5% - +3% -0.82ms - +0.46ms	-

many_updates

• Browser: chrome-headless 106.0.5249.119
• Sample size: 70
• Built by: Benchmarks #924

• Commit: deb2646

duration

Version	Avg time	vs preact-master	vs preact-local	vs preact-hooks
preact-master	35.04ms - 37.11ms	-	unsure 🔍 -5% - +3% -1.78ms - +1.06ms	faster ✔ 1% - 8% 0.35ms - 2.90ms
preact-local	35.46ms - 37.41ms	unsure 🔍 -3% - +5% -1.06ms - +1.78ms	-	faster ✔ 0% - 7% 0.04ms - 2.49ms
preact-hooks	36.96ms - 38.44ms	slower ❌ 1% - 8% 0.35ms - 2.90ms	slower ❌ 0% - 7% 0.04ms - 2.49ms	-

usedJSHeapSize

Version	Avg time	vs preact-master	vs preact-local	vs preact-hooks
preact-master	4.96ms - 4.97ms	-	unsure 🔍 -0% - +0% -0.01ms - +0.00ms	faster ✔ 8% - 8% 0.44ms - 0.45ms
preact-local	4.97ms - 4.97ms	unsure 🔍 -0% - +0% -0.00ms - +0.01ms	-	faster ✔ 8% - 8% 0.44ms - 0.44ms
preact-hooks	5.41ms - 5.41ms	slower ❌ 9% - 9% 0.44ms - 0.45ms	slower ❌ 9% - 9% 0.44ms - 0.44ms	-

text_update

• Browser: chrome-headless 106.0.5249.119
• Sample size: 50
• Built by: Benchmarks #924

• Commit: deb2646

duration

Version	Avg time	vs preact-master	vs preact-local	vs preact-hooks
preact-master	2.89ms - 2.96ms	-	unsure 🔍 -1% - +2% -0.03ms - +0.06ms	faster ✔ 8% - 11% 0.25ms - 0.37ms
preact-local	2.88ms - 2.93ms	unsure 🔍 -2% - +1% -0.06ms - +0.03ms	-	faster ✔ 8% - 12% 0.27ms - 0.38ms
preact-hooks	3.18ms - 3.28ms	slower ❌ 8% - 13% 0.25ms - 0.37ms	slower ❌ 9% - 13% 0.27ms - 0.38ms	-

usedJSHeapSize

Version	Avg time	vs preact-master	vs preact-local	vs preact-hooks
preact-master	1.14ms - 1.14ms	-	unsure 🔍 -0% - +0% -0.00ms - +0.00ms	faster ✔ 1% - 1% 0.02ms - 0.02ms
preact-local	1.14ms - 1.14ms	unsure 🔍 -0% - +0% -0.00ms - +0.00ms	-	faster ✔ 1% - 1% 0.02ms - 0.02ms
preact-hooks	1.16ms - 1.16ms	slower ❌ 1% - 1% 0.02ms - 0.02ms	slower ❌ 1% - 1% 0.02ms - 0.02ms	-

todo

• Browser: chrome-headless 106.0.5249.119
• Sample size: 90
• Built by: Benchmarks #924

• Commit: deb2646

duration

Version	Avg time	vs preact-master	vs preact-local	vs preact-hooks
preact-master	56.31ms - 56.83ms	-	unsure 🔍 -0% - +1% -0.05ms - +0.62ms	faster ✔ 4% - 6% 2.63ms - 3.53ms
preact-local	56.08ms - 56.50ms	unsure 🔍 -1% - +0% -0.62ms - +0.05ms	-	faster ✔ 5% - 6% 2.94ms - 3.78ms
preact-hooks	59.28ms - 60.02ms	slower ❌ 5% - 6% 2.63ms - 3.53ms	slower ❌ 5% - 7% 2.94ms - 3.78ms	-

usedJSHeapSize

Version	Avg time	vs preact-master	vs preact-local	vs preact-hooks
preact-master	1.43ms - 1.43ms	-	unsure 🔍 -0% - +0% -0.00ms - +0.00ms	faster ✔ 2% - 3% 0.04ms - 0.04ms
preact-local	1.43ms - 1.43ms	unsure 🔍 -0% - +0% -0.00ms - +0.00ms	-	faster ✔ 2% - 3% 0.03ms - 0.04ms
preact-hooks	1.47ms - 1.47ms	slower ❌ 2% - 3% 0.04ms - 0.04ms	slower ❌ 2% - 3% 0.03ms - 0.04ms	-

_{tachometer-reporter-action v2 for Benchmarks}

[coveralls]

Coverage remained the same at 99.531% when pulling deb2646 on fix-finding-keyed-elements into c629fc2 on master.

[github-actions]

Size Change: -1 B

Total Size: 53.1 kB

Filename	Size	Change
dist/preact.js	4.06 kB	-1 B

ℹ️ View Unchanged

Filename	Size	Change
compat/dist/compat.js	3.81 kB	0 B
compat/dist/compat.module.js	3.75 kB	0 B
compat/dist/compat.umd.js	3.87 kB	0 B
debug/dist/debug.js	3.01 kB	0 B
debug/dist/debug.module.js	3.01 kB	0 B
debug/dist/debug.umd.js	3.09 kB	0 B
devtools/dist/devtools.js	231 B	0 B
devtools/dist/devtools.module.js	240 B	0 B
devtools/dist/devtools.umd.js	314 B	0 B
dist/preact.min.js	4.08 kB	0 B
dist/preact.min.module.js	4.08 kB	0 B
dist/preact.min.umd.js	4.11 kB	0 B
dist/preact.module.js	4.07 kB	0 B
dist/preact.umd.js	4.12 kB	0 B
hooks/dist/hooks.js	1.55 kB	0 B
hooks/dist/hooks.module.js	1.59 kB	0 B
hooks/dist/hooks.umd.js	1.64 kB	0 B
jsx-runtime/dist/jsxRuntime.js	358 B	0 B
jsx-runtime/dist/jsxRuntime.module.js	324 B	0 B
jsx-runtime/dist/jsxRuntime.umd.js	439 B	0 B
test-utils/dist/testUtils.js	442 B	0 B
test-utils/dist/testUtils.module.js	444 B	0 B
test-utils/dist/testUtils.umd.js	526 B	0 B

_{compressed-size-action}

[andrewiggins]

Huh, I surprised this change fixes that issue. Definitely an important issue to fix ofc. I'm gonna look into this as well to refresh my memory on how this works.