Expect macros don't work with string interpolation in Scala 2.13.14

[zainab-ali]

This issue was copied over from: disneystreaming/weaver-test#750
It was opened by: aragutskiy

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After updating Scala from 2.13.13 to 2.13.14 I got compilation error: "possible missing interpolator: detected an interpolated expression".

Doesn't work:

val world = "World"
assert(s"Hello, $world!".contains("Hell"))

Works:

val world = "World"
val assertion = s"Hello, $world!".contains("Hell")
assert(assertion)

[zainab-ali]

This comment was copied over from: disneystreaming/weaver-test#750 (comment)
It was written by: SethTisue

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Curious what happened here — what Scala change was responsible. cc lrytz som-snytt

[zainab-ali]

This comment was copied over from: disneystreaming/weaver-test#750 (comment)
It was written by: som-snytt

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Probably the same as etorreborre/specs2#1237
or explanation on the forum
https://users.scala-lang.org/t/regression-with-macro-and-interpolation-linting/9986/2?u=som-snytt

where -Wmacros:after (or -Wmacros:both) enables linting (for this particular lint) the tree after expansion.

Note that the new default -Wmacros:default was improved to make it less likely that -Wmacros:after is intended.

(-Wmacros:none turns off linting of trees that are transformed by macros, either before or after expansion.)

SethTisue It ought to be mentioned in the release notes. It affects only those warning expanded trees, but that may not be a niche of the community.

[zainab-ali]

This comment was copied over from: disneystreaming/weaver-test#750 (comment)
It was written by: som-snytt

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I submitted a provisional PR with expecty, which I assume is used here. That would pass the lint irrespective of other settings.

[zainab-ali]

This comment was copied over from: disneystreaming/weaver-test#750 (comment)
It was written by: SethTisue

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It ought to be mentioned in the release notes

ah, indeed, https://github.com/scala/scala/releases/tag/v2.13.14 references scala/scala#10693

and the expecty PR Som mentions is eed3si9n/expecty#161

[zainab-ali]

Closing as a duplicate.