Upgrade scalafmt in order to get SIP-64 syntax support

.scalafmt.conf

@@ -1,14 +1,5 @@
-version = "3.8.3"
+version = "3.8.4-RC4"
 align.preset = more
 maxColumn = 120
 runner.dialect = scala3
 assumeStandardLibraryStripMargin = true
-# https://github.com/scalameta/scalameta/issues/4090
-project.excludePaths = [
-    "glob:**/ch04/src/**.scala",
-    "glob:**/ch06/src/Cat.scala",
-    "glob:**/ch07/src/*.scala",
-    "glob:**/ch08/src/*.scala",
-    "glob:**/ch09/src/*.scala",
-    "glob:**/ch09/src/*.sc",
-  ]

ch04/src/Cat.scala

@@ -5,7 +5,7 @@ final case class Cat(name: String, age: Int, color: String)
 object Cat:
   given catDisplay: Display[Cat]:
     def display(cat: Cat): String =
-      val name = Display.display(cat.name)
-      val age = Display.display(cat.age)
+      val name  = Display.display(cat.name)
+      val age   = Display.display(cat.age)
       val color = Display.display(cat.color)
       s"$name is a $age year-old $color cat."

ch04/src/Display.scala

@@ -2,11 +2,10 @@ package ch04
 
 /*
 4.5 Exercise: Display Library
-*/
+ */
 trait Display[A]:
   def display(value: A): String
 
-
 object Display:
   given stringDisplay: Display[String]:
     def display(input: String): String = input
@@ -23,4 +22,4 @@ object Display:
 object DisplaySyntax:
   extension [A](value: A)(using p: Display[A])
     def display: String = p.display(value)
-    def print: Unit = Display.print(value)
+    def print: Unit     = Display.print(value)

ch06/src/Cat.scala

@@ -1,16 +1,16 @@
 package ch06
 
 import cats.{Eq, Show}
-import cats.syntax.show.toShow  // A.show if Show[A] exists 
-import cats.syntax.eq.catsSyntaxEq  // ===
+import cats.syntax.show.toShow     // A.show if Show[A] exists
+import cats.syntax.eq.catsSyntaxEq // ===
 
 final case class Cat(name: String, age: Int, color: String)
 
 object Cat:
   /*
   6.2.1.1 Exercise: Cat Show
   Re-implement the Cat application from Section 4.5.1 using Show instead of Display.
- */
+   */
   given Show[Cat]:
     override def show(cat: Cat): String =
       val name  = cat.name.show
@@ -21,9 +21,9 @@ object Cat:
   /*
   6.3.4.1 Exercise: Equality, Liberty, and Felinity
   Implement an instance of Eq for our running Cat example.
-  */
+   */
   given Eq[Cat]:
     override def eqv(x: Cat, y: Cat): Boolean =
       (x.name === y.name) &&
         (x.age === y.age) &&
-        (x.color === y.color)
+        (x.color === y.color)

ch07/src/Lib.scala

@@ -1,10 +1,10 @@
 package ch07
 
 /*
-We can use Semigroups and Monoids by importing two things: the type classes themselves, 
+We can use Semigroups and Monoids by importing two things: the type classes themselves,
 and the semigroup syntax to give us the |+| operator.
-*/
-import cats.syntax.semigroup.catsSyntaxSemigroup  // A |+| A if Semigroup[A] exists
+ */
+import cats.syntax.semigroup.catsSyntaxSemigroup // A |+| A if Semigroup[A] exists
 
 object Lib:
 
@@ -47,4 +47,4 @@ object Lib:
         o1.quantity + o2.quantity
       )
 
-    def empty = Order(0, 0)
+    def empty = Order(0, 0)

ch07/src/Monoid.scala

@@ -4,7 +4,7 @@ trait Monoid[A] extends Semigroup[A]:
   def empty: A
 
 object Monoid:
-  def apply[A : Monoid as m]: Monoid[A] = m
+  def apply[A: Monoid as m]: Monoid[A] = m
 
   /*
   7.2.0.1 Exercise: The Truth About Monoids
@@ -33,12 +33,12 @@ object Monoid:
   /*
   7.2.0.2 Exercise: All Set for Monoids
   What monoids and semigroups are there for sets?
-  */
+   */
   given setUnionMonoid: [A] => Monoid[Set[A]]:
     def combine(a: Set[A], b: Set[A]) = a.union(b)
     def empty                         = Set.empty[A]
 
   given symDiffMonoid: [A] => Monoid[Set[A]]:
     def combine(a: Set[A], b: Set[A]): Set[A] =
       (a.diff(b)).union(b.diff(a))
-    def empty: Set[A] = Set.empty
+    def empty: Set[A] = Set.empty

ch08/src/Codec.scala

@@ -16,10 +16,10 @@ trait Codec[A]:
       override def decode(value: String): B =
         dec(self.decode(value))
 
-def encode[A : Codec as c](value: A): String =
+def encode[A: Codec as c](value: A): String =
   c.encode(value)
 
-def decode[A : Codec as c](value: String): A =
+def decode[A: Codec as c](value: String): A =
   c.decode(value)
 
 object Codec:
@@ -37,5 +37,5 @@ object Codec:
     stringCodec.imap(_.toDouble, _.toString)
 
   // Implement a Codec for the Box type.
-  given boxCodec: [A : Codec as c] => Codec[Box[A]] =
+  given boxCodec: [A: Codec as c] => Codec[Box[A]] =
     c.imap[Box[A]](Box(_), _.value)

ch08/src/Display.scala

@@ -36,7 +36,7 @@ object Display:
   // Given a Display[A], and a Box[A], we can create
   // Display[Box[A]] by the reverse mapping Box[A] => A.
   // The forward mapping would be A => Box[A].
-  
+
   // Parameterized typeclass with named context bound.
-  given [A : Display as d] => Display[Box[A]] =
+  given [A: Display as d] => Display[Box[A]] =
     d.contramap[Box[A]](_.value)

ch08/src/Tree.scala

@@ -10,19 +10,19 @@ object Tree:
   import Tree.*
 
   /* 8.5.4 Exercise: Branching out with Functors
-  Write a Functor for the following binary tree data type. 
+  Write a Functor for the following binary tree data type.
   Verify that the code works as expected on instances of Branch and Leaf.
- */
+   */
   given Functor[Tree]:
     override def map[A, B](fa: Tree[A])(f: A => B): Tree[B] =
       fa match
         case Branch(l, r) => Branch(map(l)(f), map(r)(f))
         case Leaf(value)  => Leaf(f(value))
 
-  // The compiler can find a Functor instance for Tree but not for Branch or Leaf 
+  // The compiler can find a Functor instance for Tree but not for Branch or Leaf
   // (Functor is invariant in F). Let's add some smart constructors to compensate.
   def branch[A](left: Tree[A], right: Tree[A]): Tree[A] =
     Branch(left, right)
 
   def leaf[A](value: A): Tree[A] =
-    Leaf(value)
+    Leaf(value)

ch09/src/Lib.scala

@@ -2,9 +2,9 @@ package ch09
 
 import cats.{Eval, MonadError}
 import cats.data.{Reader, Writer, State}
-import cats.syntax.applicative.catsSyntaxApplicativeId  // pure
-import cats.syntax.writer.catsSyntaxWriterId  // tell
-import cats.syntax.apply.catsSyntaxApplyOps  // *>
+import cats.syntax.applicative.catsSyntaxApplicativeId // pure
+import cats.syntax.writer.catsSyntaxWriterId           // tell
+import cats.syntax.apply.catsSyntaxApplyOps            // *>
 
 object Lib:
   /*

ch09/src/Monad.scala

@@ -25,4 +25,4 @@ trait Monad[F[_]]:
       def pure[A](a: A): Id[A] = a
 
       def flatMap[A, B](value: Id[A])(f: A => Id[B]): Id[B] =
-        f(value)
+        f(value)

ch09/src/Tree.scala

@@ -12,32 +12,32 @@ package ch09
   despite the fact that we haven’t directly implemented flatMap or map on Tree.
 
   Don't feel you have to make tailRecM tail-recursive. Doing so is quite difficult.
-    */
-  enum Tree[A]:
-    case Leaf(value: A)
-    case Branch(left: Tree[A], right: Tree[A])
+ */
+enum Tree[A]:
+  case Leaf(value: A)
+  case Branch(left: Tree[A], right: Tree[A])
 
-  object Tree:
-    import Tree.*
+object Tree:
+  import Tree.*
 
-    given cats.Monad[Tree]:
-      override def pure[A](x: A): Tree[A] =
-          Leaf(x)
+  given cats.Monad[Tree]:
+    override def pure[A](x: A): Tree[A] =
+      Leaf(x)
 
-      override def flatMap[A, B](t: Tree[A])(f: A => Tree[B]): Tree[B] =
+    override def flatMap[A, B](t: Tree[A])(f: A => Tree[B]): Tree[B] =
       t match
-          case Leaf(x)      => f(x)
-          case Branch(l, r) => Branch(flatMap(l)(f), flatMap(r)(f))
+        case Leaf(x)      => f(x)
+        case Branch(l, r) => Branch(flatMap(l)(f), flatMap(r)(f))
 
-      // Not stack-safe!
-      override def tailRecM[A, B](a: A)(f: A => Tree[Either[A, B]]): Tree[B] =
+    // Not stack-safe!
+    override def tailRecM[A, B](a: A)(f: A => Tree[Either[A, B]]): Tree[B] =
       flatMap(f(a)):
-          case Left(value)  => tailRecM(value)(f)
-          case Right(value) => Leaf(value)
+        case Left(value)  => tailRecM(value)(f)
+        case Right(value) => Leaf(value)
 
-    // Smart constructors to help the compiler.
-    def branch[A](left: Tree[A], right: Tree[A]): Tree[A] =
-      Branch(left, right)
+  // Smart constructors to help the compiler.
+  def branch[A](left: Tree[A], right: Tree[A]): Tree[A] =
+    Branch(left, right)
 
-    def leaf[A](value: A): Tree[A] =
-      Leaf(value)
+  def leaf[A](value: A): Tree[A] =
+    Leaf(value)

ch09/src/ch09.worksheet.sc

@@ -1,8 +1,8 @@
 import cats.{Id, Eval, MonadError}
 import cats.data.{Reader, Writer, State}
-import cats.syntax.functor.toFunctorOps  // map
-import cats.syntax.flatMap.toFlatMapOps  // flatMap
-import cats.syntax.applicative.catsSyntaxApplicativeId   // pure
+import cats.syntax.functor.toFunctorOps                // map
+import cats.syntax.flatMap.toFlatMapOps                // flatMap
+import cats.syntax.applicative.catsSyntaxApplicativeId // pure
 import cats.syntax.writer.catsSyntaxWriterId           // tell
 
 // 9.3 The Identity Monad