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Used variable for instantiation differs in Scala 3

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#278 3 comments 0 reactions 0 assignees View on GitHub

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
35/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Stale
Tech stack
scala
Domain
backend

Research direction

Start with the linked Demo Repository and run the provided Main example under Scala 2.13.30 and Scala 3.0.2. Trace how wire[Basket] selects a Berry when blackberry and lazy raspberry are in scope. Done means the Scala 3 result is made consistent with the intended behavior, with a regression test covering this example.

Written by the indexing model from the issue text.

Description

Demo Repository

The following code produces a different outcome when using Scala 3:

import com.softwaremill.macwire.wire

case class Berry(var name: String)
case class Basket(berry: Berry)

object Main extends App {
  val blackberry: Berry = Berry("blackberry")
  val basket: Basket = {
      lazy val raspberry: Berry = Berry("raspberry")
      wire[Basket]
  }
  println(basket.berry.name) // scala 2.13.30 raspberry, scala 3.0.2 blackberry
}
Dominant language
Scala
Stars
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Forks
77
Avg merge
9m
Merged PRs (30d)
4

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  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

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