Unexpectedly found "! ~" when slicing source, but expected " "

[charlesfries]

Seeing the following build time warning in 0.12.0:

[Babel: ember-prism > applyPatches]unexpectedly found "! ~" when slicing source, but expected " "
unexpectedly found "! ~" when slicing source, but expected " "
unexpectedly found "! ~" when slicing source, but expected " "
unexpectedly found "! ~" when slicing source, but expected " "

"ember-cli": "~4.1.0",
"ember-prism": "^0.12.0",
"ember-source": "~3.28.8",

Seems to be caused by these template comments:

ember-prism/addon/components/code-block.hbs

Line 4 in c9b1ba0

{{~! ~}}

[RobbieTheWagner]

@charlesfries thanks for reporting! We were using that to remove whitespace before. I wonder why it all the sudden stopped working?

[charlesfries]

Seems to be related to [email protected] emberjs/ember.js#19392

Downgrading ember-cli-htmlbars to 6.0.0 fixes the issue on my fork.