chore: deprecate scala.util.ChainingOps

Author: hamzaremmal

compiler/test/dotty/tools/utils.scala

@@ -12,7 +12,7 @@ import scala.io.Source
 import scala.jdk.StreamConverters._
 import scala.reflect.ClassTag
 import scala.util.Using.{Releasable, resource}
-import scala.util.chaining.given
+import scala.util.chaining.*
 import scala.util.control.{ControlThrowable, NonFatal}
 
 import dotc.config.CommandLineParser

library/src/scala/util/ChainingOps.scala

@@ -16,12 +16,16 @@ package util
 import scala.language.`2.13`
 import scala.language.implicitConversions
 
+@deprecated(message = "ChainingSyntax will be removed in the future. Refer to `scala.util.chaining` instead.",
+            since   = "3.10.0")
 trait ChainingSyntax {
-  @inline implicit final def scalaUtilChainingOps[A](a: A): ChainingOps[A] = new ChainingOps(a)
+  @deprecated(message = "Use extension methods in `scala.util.chaining` instead.", since = "3.10.0")
+  @inline final def scalaUtilChainingOps[A](a: A): ChainingOps[A] = new ChainingOps(a)
 }
 
 /** Adds chaining methods `tap` and `pipe` to every type.
  */
+@deprecated(message = "Use extension methods in `scala.util.chaining` instead.", since = "3.10.0")
 final class ChainingOps[A](private val self: A) extends AnyVal {
   /** Applies `f` to the value for its side effects, and returns the original value.
     *
@@ -37,10 +41,7 @@ final class ChainingOps[A](private val self: A) extends AnyVal {
     *  @tparam U     the result type of the function `f`.
     *  @return       the original value `self`.
     */
-  def tap[U](f: A => U): A = {
-    f(self)
-    self
-  }
+  def tap[U](f: A => U): A = scala.util.chaining.tap(self)(x => f(x))
 
   /** Converts the value by applying the function `f`.
     *
@@ -62,5 +63,5 @@ final class ChainingOps[A](private val self: A) extends AnyVal {
     *  @return       a new value resulting from applying the given function
     *                `f` to this value.
     */
-  def pipe[B](f: A => B): B = f(self)
+  def pipe[B](f: A => B): B = scala.util.chaining.pipe(self)(f)
 }

library/src/scala/util/package.scala

@@ -14,9 +14,15 @@ package scala
 
 import scala.language.`2.13`
 
+import scala.annotation.nowarn
+
 package object util {
   /**
-   * Adds chaining methods `tap` and `pipe` to every type. See [[ChainingOps]].
+   * Adds chaining methods `tap` and `pipe` to every type.
    */
-  object chaining extends ChainingSyntax
+  @nowarn("msg=ChainingSyntax will be removed in the future")
+  object chaining extends ChainingSyntax:
+    extension[A](x: A)
+      inline def tap(inline f: A => Unit): x.type = { f(x); x }
+      inline def pipe[B](inline f: A => B): B = f(x)
 }

tests/neg/i15998.check

@@ -15,7 +15,6 @@
   |              import scala.math.BigDecimal.int2bigDecimal
   |              import scala.math.BigInt.int2bigInt
   |              import scala.math.Ordered.orderingToOrdered
-  |              import scala.util.chaining.scalaUtilChainingOps
   |
   |
   | longer explanation available when compiling with `-explain`

tests/run/i10889.scala

@@ -1,5 +1,5 @@
 import scala.annotation.tailrec
-import scala.util.chaining.given
+import scala.util.chaining.*
 
 object Test {
   class Ctx

tests/run/i11571.scala

@@ -1,4 +1,4 @@
-import util.chaining.scalaUtilChainingOps
+import util.chaining.*
 object Test extends App {
   def x = 42.tap(println(_))
   def y = 27.tap(println(_))