Remove '@ember/application's lazy load / onLoad stuff (private API)

[NullVoxPopuli]

Removes

• @ember/application/lib/lazy_load
  • exports
    • onLoad, private
    • _loaded, implicit private (internal)
    • runLoadHooks, private
• ember-testing/lib/initializers
  • imports
    • onLoad from @ember/application/lib/lazy_load
  • exports: none
  • no remaining code in the file once onLoad is removed

Other things I found:

• Test.registerHelper is a thing -- why? (before we had async testing? or ESM?)
  • app.advanceReadiness() can't be called in here anymore -- which is probably fine.
    • GH search for advance readiness: https://github.com/search?q=advanceReadiness%28%29+-repo%3Aemberjs%2Fember.js&type=code
      • .erb files
      • .coffee files
      • using global App or Ember
    • mostly used in normal-looking code, I suppose, not in a registerHelper
      • most usages look like they in old / unsupported code
      • but a few are used in ways that are supported and advanceReadiness is a public api and still hav a fair number of tests covering its usage

---

According to the size comment, this PR removes 0.8KB

local bench:

    Benchmark Results Summary    

duration phase no difference [-110ms to 71ms]
renderEnd phase no difference [-3ms to 0ms]
render1000Items1End phase no difference [-13ms to 8ms]
clearItems1End phase no difference [-1ms to 8ms]
render1000Items2End phase no difference [-4ms to 7ms]
clearItems2End phase no difference [0ms to 3ms]
render5000Items1End phase no difference [-29ms to 17ms]
clearManyItems1End phase no difference [-5ms to 2ms]
render5000Items2End phase no difference [-67ms to 0ms]
clearManyItems2End phase no difference [0ms to 1ms]
render1000Items3End phase no difference [0ms to 0ms]
append1000Items1End phase no difference [-17ms to 0ms]
append1000Items2End phase no difference [0ms to 33ms]
updateEvery10thItem1End phase no difference [0ms to 16ms]
updateEvery10thItem2End phase no difference [-1ms to 0ms]
selectFirstRow1End phase no difference [0ms to 0ms]
selectSecondRow1End phase no difference [0ms to 0ms]
removeFirstRow1End phase no difference [0ms to 0ms]
removeSecondRow1End phase no difference [0ms to 0ms]
swapRows1End phase no difference [0ms to 0ms]
swapRows2End phase no difference [0ms to 0ms]
clearItems4End phase no difference [-1ms to 0ms]
paint phase no difference [0ms to 0ms]

[github-actions]

Estimated Asset Sizes

Diff

--- main/out.txt	2026-01-16 20:37:26.000000000 +0000
+++ pr/./pr-21087587728/out.txt	2026-01-17 03:20:12.000000000 +0000
@@ -1,16 +1,16 @@
-╔═══════╤══════════╤══════════╗
-║       │ Min      │ Gzip     ║
-╟───────┼──────────┼──────────╢
-║ Total │ 352.2 KB │ 203.5 KB ║
-╚═══════╧══════════╧══════════╝
+╔═══════╤═══════════╤══════════╗
+║       │ Min       │ Gzip     ║
+╟───────┼───────────┼──────────╢
+║ Total │ 351.43 KB │ 202.8 KB ║
+╚═══════╧═══════════╧══════════╝
 
 ╔══════════════════════╤═══════════╤═══════════╗
 ║ @ember/*             │ Min       │ Gzip      ║
 ╟──────────────────────┼───────────┼───────────╢
-║ Total                │ 313.81 KB │ 181.76 KB ║
+║ Total                │ 313.05 KB │ 181.06 KB ║
 ╟──────────────────────┼───────────┼───────────╢
 ║ -internals           │ 36.61 KB  │ 25.99 KB  ║
-║ application          │ 13.24 KB  │ 7.99 KB   ║
+║ application          │ 12.47 KB  │ 7.29 KB   ║
 ║ array                │ 13.05 KB  │ 7.54 KB   ║
 ║ canary-features      │ 304 B     │ 419 B     ║
 ║ component            │ 2.05 KB   │ 1.61 KB   ║

Details

This PR

main

╔═══════╤═══════════╤══════════╗ ║ │ Min │ Gzip ║ ╟───────┼───────────┼──────────╢ ║ Total │ 351.43 KB │ 202.8 KB ║ ╚═══════╧═══════════╧══════════╝ ╔══════════════════════╤═══════════╤═══════════╗ ║ @ember/* │ Min │ Gzip ║ ╟──────────────────────┼───────────┼───────────╢ ║ Total │ 313.05 KB │ 181.06 KB ║ ╟──────────────────────┼───────────┼───────────╢ ║ -internals │ 36.61 KB │ 25.99 KB ║ ║ application │ 12.47 KB │ 7.29 KB ║ ║ array │ 13.05 KB │ 7.54 KB ║ ║ canary-features │ 304 B │ 419 B ║ ║ component │ 2.05 KB │ 1.61 KB ║ ║ controller │ 1.96 KB │ 1.45 KB ║ ║ debug │ 11.73 KB │ 8.14 KB ║ ║ deprecated-features │ 31 B │ 77 B ║ ║ destroyable │ 561 B │ 383 B ║ ║ enumerable │ 259 B │ 387 B ║ ║ helper │ 1.08 KB │ 802 B ║ ║ instrumentation │ 2.43 KB │ 1.78 KB ║ ║ modifier │ 1.22 KB │ 978 B ║ ║ object │ 35.98 KB │ 22.1 KB ║ ║ owner │ 159 B │ 178 B ║ ║ renderer │ 630 B │ 471 B ║ ║ routing │ 59.37 KB │ 33.93 KB ║ ║ runloop │ 2.36 KB │ 1.5 KB ║ ║ service │ 1 KB │ 858 B ║ ║ template │ 654 B │ 543 B ║ ║ template-compilation │ 429 B │ 366 B ║ ║ template-compiler │ 123.33 KB │ 59.68 KB ║ ║ template-factory │ 370 B │ 351 B ║ ║ test │ 923 B │ 627 B ║ ║ utils │ 4.11 KB │ 3.63 KB ║ ║ version │ 55 B │ 131 B ║ ╚══════════════════════╧═══════════╧═══════════╝ ╔═════════════════╤══════════╤══════════╗ ║ @glimmer/* │ Min │ Gzip ║ ╟─────────────────┼──────────┼──────────╢ ║ Total │ 38.38 KB │ 21.74 KB ║ ╟─────────────────┼──────────┼──────────╢ ║ destroyable │ 2.78 KB │ 1.38 KB ║ ║ encoder │ 81 B │ 171 B ║ ║ env │ 38 B │ 87 B ║ ║ global-context │ 886 B │ 545 B ║ ║ manager │ 977 B │ 627 B ║ ║ node │ 175 B │ 243 B ║ ║ opcode-compiler │ 1.11 KB │ 905 B ║ ║ owner │ 159 B │ 202 B ║ ║ program │ 252 B │ 333 B ║ ║ reference │ 548 B │ 544 B ║ ║ runtime │ 10.32 KB │ 5.19 KB ║ ║ tracking │ 1.34 KB │ 1.18 KB ║ ║ util │ 1.94 KB │ 1.6 KB ║ ║ validator │ 15.53 KB │ 6.9 KB ║ ║ vm │ 495 B │ 569 B ║ ║ wire-format │ 1.84 KB │ 1.35 KB ║ ╚═════════════════╧══════════╧══════════╝

╔═══════╤══════════╤══════════╗ ║ │ Min │ Gzip ║ ╟───────┼──────────┼──────────╢ ║ Total │ 352.2 KB │ 203.5 KB ║ ╚═══════╧══════════╧══════════╝ ╔══════════════════════╤═══════════╤═══════════╗ ║ @ember/* │ Min │ Gzip ║ ╟──────────────────────┼───────────┼───────────╢ ║ Total │ 313.81 KB │ 181.76 KB ║ ╟──────────────────────┼───────────┼───────────╢ ║ -internals │ 36.61 KB │ 25.99 KB ║ ║ application │ 13.24 KB │ 7.99 KB ║ ║ array │ 13.05 KB │ 7.54 KB ║ ║ canary-features │ 304 B │ 419 B ║ ║ component │ 2.05 KB │ 1.61 KB ║ ║ controller │ 1.96 KB │ 1.45 KB ║ ║ debug │ 11.73 KB │ 8.14 KB ║ ║ deprecated-features │ 31 B │ 77 B ║ ║ destroyable │ 561 B │ 383 B ║ ║ enumerable │ 259 B │ 387 B ║ ║ helper │ 1.08 KB │ 802 B ║ ║ instrumentation │ 2.43 KB │ 1.78 KB ║ ║ modifier │ 1.22 KB │ 978 B ║ ║ object │ 35.98 KB │ 22.1 KB ║ ║ owner │ 159 B │ 178 B ║ ║ renderer │ 630 B │ 471 B ║ ║ routing │ 59.37 KB │ 33.93 KB ║ ║ runloop │ 2.36 KB │ 1.5 KB ║ ║ service │ 1 KB │ 858 B ║ ║ template │ 654 B │ 543 B ║ ║ template-compilation │ 429 B │ 366 B ║ ║ template-compiler │ 123.33 KB │ 59.68 KB ║ ║ template-factory │ 370 B │ 351 B ║ ║ test │ 923 B │ 627 B ║ ║ utils │ 4.11 KB │ 3.63 KB ║ ║ version │ 55 B │ 131 B ║ ╚══════════════════════╧═══════════╧═══════════╝ ╔═════════════════╤══════════╤══════════╗ ║ @glimmer/* │ Min │ Gzip ║ ╟─────────────────┼──────────┼──────────╢ ║ Total │ 38.38 KB │ 21.74 KB ║ ╟─────────────────┼──────────┼──────────╢ ║ destroyable │ 2.78 KB │ 1.38 KB ║ ║ encoder │ 81 B │ 171 B ║ ║ env │ 38 B │ 87 B ║ ║ global-context │ 886 B │ 545 B ║ ║ manager │ 977 B │ 627 B ║ ║ node │ 175 B │ 243 B ║ ║ opcode-compiler │ 1.11 KB │ 905 B ║ ║ owner │ 159 B │ 202 B ║ ║ program │ 252 B │ 333 B ║ ║ reference │ 548 B │ 544 B ║ ║ runtime │ 10.32 KB │ 5.19 KB ║ ║ tracking │ 1.34 KB │ 1.18 KB ║ ║ util │ 1.94 KB │ 1.6 KB ║ ║ validator │ 15.53 KB │ 6.9 KB ║ ║ vm │ 495 B │ 569 B ║ ║ wire-format │ 1.84 KB │ 1.35 KB ║ ╚═════════════════╧══════════╧══════════╝

[kategengler]

Test.registerHelper I believe is only vestigial (but I haven't confirmed that we don't call it somewhere) from before we redid ember testing with https://github.com/emberjs/rfcs/blob/main/text/0268-acceptance-testing-refactor.md. Here are the docs from the old-times https://guides.emberjs.com/v2.16.0/testing/acceptance/#toc_custom-test-helpers

This was quite a long time ago and we never deprecated the old style of testing, afaik. BUT, I suspect it does not work at all in even 6.0 or earlier. I think we should see what, if anything of ember-testing is still in use at 6.0.

advanceReadiness and deferReadiness are indeed public APIs that have not been deprecated and I believe they still work. They were commonly called from initializers.

Overall, I think this looks good but I wonder if we should land it with 7.0 just to be safe.