I m getting this crash running `jsTest` and `jsBrowserTest`

Question

I m getting this crash running `jsTest` and `jsBrowserTest` on our CI environments I m still trying to isolate exactly what needs to go wrong to trigger this crash ``` Uncaught ReferenceError jsDeleteProperty is not defined at tmp karma webpack 738366 commons js 405 5 ReferenceError jsDeleteProperty is not defined at InternalHashCodeMap createJsMap as createJsMap 8hfwp5 k$ tmp karma webpack 738366 commons js 405 5 at new InternalHashCodeMap tmp karma webpack 738366 commons js 11762 30 at HashMap init $Init$ 0 tmp karma webpack 738366 commons js 11390 25 at HashMap init $Init$ 1 tmp karma webpack 738366 commons js 11397 5 at LinkedHashMap init $Init$ 1 tmp karma webpack 738366 commons js 12095 5 at LinkedHashMap init $Init$ 2 tmp karma webpack 738366 commons js 12104 5 at LinkedHashMap init $Create$ 2 tmp karma webpack 738366 commons js 12108 12 at mapOf tmp karma webpack 738366 commons js 2718 44 at init properties TestApi kt iy7e2c tmp karma webpack 738366 commons js 18131 25 at suite tmp karma webpack 738366 commons js 18072 5 ``` When I interrogate the `common js` file I can confirm that the `jsDeleteProperty` is called ``` snip 400 lines setMetadataFor HashSet HashSet classMeta AbstractMutableSet AbstractMutableSet MutableSet undefined undefined setMetadataFor InternalHashCodeMap$iterator$1 undefined classMeta undefined MutableIterator undefined undefined function createJsMap var result = Object create null result foo = 1 jsDeleteProperty result foo return result setMetadataFor InternalMap InternalMap interfaceMeta undefined MutableIterable undefined undefined setMetadataFor InternalHashCodeMap InternalHashCodeMap classMeta undefined InternalMap undefined undefined another ~100K lines of code``` And I can also confirm that the `jsDeleteProperty` function doesn t exist I m first encountering this after upgrading to Kotlin 1 8 I haven t been able to isolate exactly what triggers this

jessewilson · Answer

My unverified guess is that ` InlineOnly` annotation on `jsDeleteProperty ` isn t honoured when emitting `createMap ` but it still prevents the function from being emitted as JS source ``` kotlin internal InlineOnly internal inline fun jsDeleteProperty obj Any property Any js delete obj property ```

jessewilson · Answer

Well I ve been looking at this for most of the day and I ve learned that the issue will be fixed in 1 8 20 The beta now reliably inlines the call to this function ``` function createJsMap var result = Object create null result foo = 1 var tmp$ret$0 Inline function kotlin js jsDeleteProperty call delete result foo tmp$ret$0 = Unit getInstance return result ```