Use scalameta scalafmt plugin

.scalafmt.conf

@@ -1,3 +1,4 @@
+version=2.0.1
 maxColumn = 110
 docstrings = JavaDoc
 newlines.penalizeSingleSelectMultiArgList = false

.travis.yml

@@ -16,7 +16,7 @@ matrix:
 
     - scala: 2.12.9
       jdk: openjdk8
-      script: sbt "++$TRAVIS_SCALA_VERSION clean" "++$TRAVIS_SCALA_VERSION test" "scalafmt::test" "test:scalafmt::test" "++$TRAVIS_SCALA_VERSION mimaReportBinaryIssues" "++$TRAVIS_SCALA_VERSION docs/makeMicrosite"
+      script: sbt "++$TRAVIS_SCALA_VERSION clean" "++$TRAVIS_SCALA_VERSION test" "scalafmtCheckAll" "scalafmtSbtCheck" "++$TRAVIS_SCALA_VERSION mimaReportBinaryIssues" "++$TRAVIS_SCALA_VERSION docs/makeMicrosite"
       #script: ./sbt "+++$TRAVIS_SCALA_VERSION clean" "+++$TRAVIS_SCALA_VERSION test" "++$TRAVIS_SCALA_VERSION docs/makeMicrosite"
 
 before_install:

algebird-benchmark/src/main/scala/com/twitter/algebird/benchmark/AsyncSummerBenchmark.scala

@@ -100,7 +100,8 @@ object AsyncSummerBenchmark {
         Counter("insertOp"),
         Counter("tuplesOut"),
         Counter("size"),
-        workPool)
+        workPool
+      )
       syncSummingQueue = new SyncSummingQueue[Long, HLL](
         bufferSize,
         flushFrequency,

algebird-benchmark/src/main/scala/com/twitter/algebird/benchmark/BloomFilterDistanceBenchmark.scala

@@ -41,18 +41,22 @@ object BloomFilterDistanceBenchmark {
     val sparseBF1: BF[String] =
       toSparse(
         BloomFilter[String](nbrOfElements, falsePositiveRate)
-          .create(randomElements: _*))
+          .create(randomElements: _*)
+      )
     val sparesBF2: BF[String] =
       toSparse(
         BloomFilter[String](nbrOfElements, falsePositiveRate)
-          .create(randomElements: _*))
+          .create(randomElements: _*)
+      )
 
     val denseBF1: BF[String] = toDense(
       BloomFilter[String](nbrOfElements, falsePositiveRate)
-        .create(randomElements: _*))
+        .create(randomElements: _*)
+    )
     val denseBF2: BF[String] = toDense(
       BloomFilter[String](nbrOfElements, falsePositiveRate)
-        .create(randomElements: _*))
+        .create(randomElements: _*)
+    )
 
   }
 }

algebird-benchmark/src/main/scala/com/twitter/algebird/benchmark/CMSHashingBenchmark.scala

@@ -41,7 +41,9 @@ object CMSHashingBenchmark {
         "11" /* eps = 0.271 */,
         "544" /* eps = 0.005 */,
         "2719" /* eps = 1E-3 */,
-        "271829" /* eps = 1E-5 */ ))
+        "271829" /* eps = 1E-5 */
+      )
+    )
     var width: Int = 0
 
     /**

algebird-bijection/src/main/scala/com/twitter/algebird/bijection/AlgebirdBijections.scala

@@ -56,7 +56,8 @@ class BijectedRing[T, U](implicit val ring: Ring[T], bij: ImplicitBijection[T, U
 
 trait AlgebirdBijections {
   implicit def semigroupBijection[T, U](
-      implicit bij: ImplicitBijection[T, U]): Bijection[Semigroup[T], Semigroup[U]] =
+      implicit bij: ImplicitBijection[T, U]
+  ): Bijection[Semigroup[T], Semigroup[U]] =
     new AbstractBijection[Semigroup[T], Semigroup[U]] {
       override def apply(sg: Semigroup[T]) =
         new BijectedSemigroup[T, U]()(sg, bij)

algebird-core/src/main/scala/com/twitter/algebird/AdaptiveVector.scala

@@ -106,7 +106,8 @@ object AdaptiveVector {
           case _ if valueIsNonZero(left.sparseValue) =>
             fromVector(
               Vector(Semigroup.plus(toVector(left): IndexedSeq[V], toVector(right): IndexedSeq[V]): _*),
-              left.sparseValue)
+              left.sparseValue
+            )
           case _ => // sparse is zero:
             fromMap(Semigroup.plus(toMap(left), toMap(right)), left.sparseValue, maxSize)
         }

algebird-core/src/main/scala/com/twitter/algebird/Aggregator.scala

@@ -69,7 +69,8 @@ object Aggregator extends java.io.Serializable {
    * Equivalent to {{{ appendSemigroup(prep, appnd, identity[T]_)(sg) }}}
    */
   def appendSemigroup[F, T](prep: F => T, appnd: (T, F) => T)(
-      implicit sg: Semigroup[T]): Aggregator[F, T, T] =
+      implicit sg: Semigroup[T]
+  ): Aggregator[F, T, T] =
     appendSemigroup(prep, appnd, identity[T] _)(sg)
 
   /**
@@ -85,7 +86,8 @@ object Aggregator extends java.io.Serializable {
    * @note The functions 'appnd' and 'prep' are expected to obey the law: {{{ appnd(t, f) == sg.plus(t, prep(f)) }}}
    */
   def appendSemigroup[F, T, P](prep: F => T, appnd: (T, F) => T, pres: T => P)(
-      implicit sg: Semigroup[T]): Aggregator[F, T, P] =
+      implicit sg: Semigroup[T]
+  ): Aggregator[F, T, P] =
     new Aggregator[F, T, P] {
       def semigroup: Semigroup[T] = sg
       def prepare(input: F): T = prep(input)
@@ -130,7 +132,8 @@ object Aggregator extends java.io.Serializable {
    * @note The function 'appnd' is expected to obey the law: {{{ appnd(t, f) == m.plus(t, appnd(m.zero, f)) }}}
    */
   def appendMonoid[F, T, P](appnd: (T, F) => T, pres: T => P)(
-      implicit m: Monoid[T]): MonoidAggregator[F, T, P] =
+      implicit m: Monoid[T]
+  ): MonoidAggregator[F, T, P] =
     new MonoidAggregator[F, T, P] {
       def monoid: Monoid[T] = m
       def prepare(input: F): T = appnd(m.zero, input)
@@ -237,8 +240,9 @@ object Aggregator extends java.io.Serializable {
    *
    * This function is like writing list.sortBy(fn).reverse.take(count).
    */
-  def sortByReverseTake[T, U: Ordering](count: Int)(
-      fn: T => U): MonoidAggregator[T, PriorityQueue[T], Seq[T]] =
+  def sortByReverseTake[T, U: Ordering](
+      count: Int
+  )(fn: T => U): MonoidAggregator[T, PriorityQueue[T], Seq[T]] =
     Aggregator.sortedReverseTake(count)(Ordering.by(fn))
 
   /**
@@ -258,8 +262,10 @@ object Aggregator extends java.io.Serializable {
    * selected. This assumes that all sampled records can fit in memory, so use this only when the
    * expected number of sampled values is small.
    */
-  def randomSample[T](prob: Double,
-                      seed: Int = DefaultSeed): MonoidAggregator[T, Option[Batched[T]], List[T]] = {
+  def randomSample[T](
+      prob: Double,
+      seed: Int = DefaultSeed
+  ): MonoidAggregator[T, Option[Batched[T]], List[T]] = {
     assert(prob >= 0 && prob <= 1, "randomSample.prob must lie in [0, 1]")
     val rng = new java.util.Random(seed)
     Preparer[T]
@@ -272,8 +278,10 @@ object Aggregator extends java.io.Serializable {
    * then 'count' total records). This assumes that all 'count' of the records can fit in memory,
    * so use this only for small values of 'count'.
    */
-  def reservoirSample[T](count: Int,
-                         seed: Int = DefaultSeed): MonoidAggregator[T, PriorityQueue[(Double, T)], Seq[T]] = {
+  def reservoirSample[T](
+      count: Int,
+      seed: Int = DefaultSeed
+  ): MonoidAggregator[T, PriorityQueue[(Double, T)], Seq[T]] = {
     val rng = new java.util.Random(seed)
     Preparer[T]
       .map(rng.nextDouble() -> _)
@@ -324,15 +332,17 @@ object Aggregator extends java.io.Serializable {
    * The items that are iterated over cannot be negative.
    */
   def approximatePercentile[T](percentile: Double, k: Int = QTreeAggregator.DefaultK)(
-      implicit num: Numeric[T]): QTreeAggregatorLowerBound[T] =
+      implicit num: Numeric[T]
+  ): QTreeAggregatorLowerBound[T] =
     QTreeAggregatorLowerBound[T](percentile, k)
 
   /**
    * Returns the intersection of a bounded percentile where the percentile is between (0,1]
    * The items that are iterated over cannot be negative.
    */
   def approximatePercentileBounds[T](percentile: Double, k: Int = QTreeAggregator.DefaultK)(
-      implicit num: Numeric[T]): QTreeAggregator[T] =
+      implicit num: Numeric[T]
+  ): QTreeAggregator[T] =
     QTreeAggregator[T](percentile, k)
 
   /**
@@ -429,8 +439,9 @@ trait Aggregator[-A, B, +C] extends java.io.Serializable { self =>
    * This returns the cumulative sum of its inputs, in the same order.
    * If the inputs are empty, the result will be empty too.
    */
-  def applyCumulatively[In <: TraversableOnce[A], Out](inputs: In)(
-      implicit bf: CanBuildFrom[In, C, Out]): Out = {
+  def applyCumulatively[In <: TraversableOnce[A], Out](
+      inputs: In
+  )(implicit bf: CanBuildFrom[In, C, Out]): Out = {
     val builder = bf()
     builder ++= cumulativeIterator(inputs.toIterator)
     builder.result
@@ -509,22 +520,28 @@ class AggregatorApplicative[I] extends Applicative[({ type L[O] = Aggregator[I,
     Aggregator.const(v)
   override def join[T, U](mt: Aggregator[I, _, T], mu: Aggregator[I, _, U]): Aggregator[I, _, (T, U)] =
     mt.join(mu)
-  override def join[T1, T2, T3](m1: Aggregator[I, _, T1],
-                                m2: Aggregator[I, _, T2],
-                                m3: Aggregator[I, _, T3]): Aggregator[I, _, (T1, T2, T3)] =
+  override def join[T1, T2, T3](
+      m1: Aggregator[I, _, T1],
+      m2: Aggregator[I, _, T2],
+      m3: Aggregator[I, _, T3]
+  ): Aggregator[I, _, (T1, T2, T3)] =
     GeneratedTupleAggregator.from3((m1, m2, m3))
 
-  override def join[T1, T2, T3, T4](m1: Aggregator[I, _, T1],
-                                    m2: Aggregator[I, _, T2],
-                                    m3: Aggregator[I, _, T3],
-                                    m4: Aggregator[I, _, T4]): Aggregator[I, _, (T1, T2, T3, T4)] =
+  override def join[T1, T2, T3, T4](
+      m1: Aggregator[I, _, T1],
+      m2: Aggregator[I, _, T2],
+      m3: Aggregator[I, _, T3],
+      m4: Aggregator[I, _, T4]
+  ): Aggregator[I, _, (T1, T2, T3, T4)] =
     GeneratedTupleAggregator.from4((m1, m2, m3, m4))
 
-  override def join[T1, T2, T3, T4, T5](m1: Aggregator[I, _, T1],
-                                        m2: Aggregator[I, _, T2],
-                                        m3: Aggregator[I, _, T3],
-                                        m4: Aggregator[I, _, T4],
-                                        m5: Aggregator[I, _, T5]): Aggregator[I, _, (T1, T2, T3, T4, T5)] =
+  override def join[T1, T2, T3, T4, T5](
+      m1: Aggregator[I, _, T1],
+      m2: Aggregator[I, _, T2],
+      m3: Aggregator[I, _, T3],
+      m4: Aggregator[I, _, T4],
+      m5: Aggregator[I, _, T5]
+  ): Aggregator[I, _, (T1, T2, T3, T4, T5)] =
     GeneratedTupleAggregator.from5((m1, m2, m3, m4, m5))
 }
 
@@ -558,7 +575,8 @@ trait MonoidAggregator[-A, B, +C] extends Aggregator[A, B, C] { self =>
    * and outputs the pair from both
    */
   def either[A2, B2, C2](
-      that: MonoidAggregator[A2, B2, C2]): MonoidAggregator[Either[A, A2], (B, B2), (C, C2)] =
+      that: MonoidAggregator[A2, B2, C2]
+  ): MonoidAggregator[Either[A, A2], (B, B2), (C, C2)] =
     new MonoidAggregator[Either[A, A2], (B, B2), (C, C2)] {
       def prepare(e: Either[A, A2]) = e match {
         case Left(a)   => (self.prepare(a), that.monoid.zero)

algebird-core/src/main/scala/com/twitter/algebird/Applicative.scala

@@ -63,11 +63,13 @@ trait Applicative[M[_]] extends Functor[M] {
       case (((t1, t2), t3), t4) => (t1, t2, t3, t4)
     }
 
-  def join[T1, T2, T3, T4, T5](m1: M[T1],
-                               m2: M[T2],
-                               m3: M[T3],
-                               m4: M[T4],
-                               m5: M[T5]): M[(T1, T2, T3, T4, T5)] =
+  def join[T1, T2, T3, T4, T5](
+      m1: M[T1],
+      m2: M[T2],
+      m3: M[T3],
+      m4: M[T4],
+      m5: M[T5]
+  ): M[(T1, T2, T3, T4, T5)] =
     joinWith(join(join(join(m1, m2), m3), m4), m5) {
       case ((((t1, t2), t3), t4), t5) => (t1, t2, t3, t4, t5)
     }
@@ -90,10 +92,12 @@ object Applicative {
   def join[M[_], T1, T2, T3](m1: M[T1], m2: M[T2], m3: M[T3])(implicit app: Applicative[M]): M[(T1, T2, T3)] =
     app.join(m1, m2, m3)
   def join[M[_], T1, T2, T3, T4](m1: M[T1], m2: M[T2], m3: M[T3], m4: M[T4])(
-      implicit app: Applicative[M]): M[(T1, T2, T3, T4)] =
+      implicit app: Applicative[M]
+  ): M[(T1, T2, T3, T4)] =
     app.join(m1, m2, m3, m4)
   def join[M[_], T1, T2, T3, T4, T5](m1: M[T1], m2: M[T2], m3: M[T3], m4: M[T4], m5: M[T5])(
-      implicit app: Applicative[M]): M[(T1, T2, T3, T4, T5)] =
+      implicit app: Applicative[M]
+  ): M[(T1, T2, T3, T4, T5)] =
     app.join(m1, m2, m3, m4, m5)
   def sequence[M[_], T](ms: Seq[M[T]])(implicit app: Applicative[M]): M[Seq[T]] =
     app.sequence(ms)
@@ -102,7 +106,8 @@ object Applicative {
    * A Generic sequence that uses CanBuildFrom
    */
   def sequenceGen[M[_], T, S[X] <: TraversableOnce[X], R[_]](
-      ms: S[M[T]])(implicit app: Applicative[M], cbf: CanBuildFrom[Nothing, T, R[T]]): M[R[T]] = {
+      ms: S[M[T]]
+  )(implicit app: Applicative[M], cbf: CanBuildFrom[Nothing, T, R[T]]): M[R[T]] = {
     val bldr = cbf()
     val mbldr = ms.toIterator.foldLeft(app.apply(bldr)) { (mb, mt) =>
       app.joinWith(mb, mt)(_ += _)

algebird-core/src/main/scala/com/twitter/algebird/Approximate.scala

@@ -72,8 +72,8 @@ object ApproximateBoolean {
 
 // Note the probWithinBounds is a LOWER BOUND (at least this probability)
 case class Approximate[N](min: N, estimate: N, max: N, probWithinBounds: Double)(
-    implicit val numeric: Numeric[N])
-    extends ApproximateSet[N] {
+    implicit val numeric: Numeric[N]
+) extends ApproximateSet[N] {
   require(numeric.lteq(min, estimate) && numeric.lteq(estimate, max))
 
   /**
@@ -101,7 +101,8 @@ case class Approximate[N](min: N, estimate: N, max: N, probWithinBounds: Double)
       n.plus(min, right.min),
       n.plus(estimate, right.estimate),
       n.plus(max, right.max),
-      probWithinBounds * right.probWithinBounds)
+      probWithinBounds * right.probWithinBounds
+    )
   }
   def -(right: Approximate[N]): Approximate[N] =
     this.+(right.negate)

algebird-core/src/main/scala/com/twitter/algebird/Batched.scala

@@ -192,8 +192,10 @@ object Batched {
    * (e.g. when there is temporary mutable state used to make
    * summation fast).
    */
-  def monoidAggregator[A, B, C](batchSize: Int,
-                                agg: MonoidAggregator[A, B, C]): MonoidAggregator[A, Batched[B], C] =
+  def monoidAggregator[A, B, C](
+      batchSize: Int,
+      agg: MonoidAggregator[A, B, C]
+  ): MonoidAggregator[A, Batched[B], C] =
     new MonoidAggregator[A, Batched[B], C] {
       def prepare(a: A): Batched[B] = Item(agg.prepare(a))
       def monoid: Monoid[Batched[B]] = new BatchedMonoid(batchSize)(agg.monoid)

algebird-core/src/main/scala/com/twitter/algebird/BloomFilter.scala

@@ -101,7 +101,8 @@ object BloomFilter {
     BloomFilter.optimalWidth(numEntries, fpProb) match {
       case None =>
         throw new java.lang.IllegalArgumentException(
-          s"BloomFilter cannot guarantee the specified false positive probability for the number of entries! (numEntries: $numEntries, fpProb: $fpProb)")
+          s"BloomFilter cannot guarantee the specified false positive probability for the number of entries! (numEntries: $numEntries, fpProb: $fpProb)"
+        )
       case Some(width) =>
         val numHashes = BloomFilter.optimalNumHashes(numEntries, width)
         BloomFilterMonoid[A](numHashes, width)(hash)
@@ -137,10 +138,12 @@ object BloomFilter {
    * (min, estimate, max) =
    *   ((1 - approxWidth) * estimate, estimate, (1 + approxWidth) * estimate)
    */
-  def sizeEstimate(numBits: Int,
-                   numHashes: Int,
-                   width: Int,
-                   approximationWidth: Double = 0.05): Approximate[Long] = {
+  def sizeEstimate(
+      numBits: Int,
+      numHashes: Int,
+      width: Int,
+      approximationWidth: Double = 0.05
+  ): Approximate[Long] = {
     assert(0 <= approximationWidth && approximationWidth < 1, "approximationWidth must lie in [0, 1)")
 
     /**
@@ -636,11 +639,13 @@ case class BFHash[A](numHashes: Int, width: Int)(implicit hash: Hash128[A]) {
   }
 
   @annotation.tailrec
-  private def nextHash(valueToHash: A,
-                       hashIndex: Int,
-                       buffer: Array[Int],
-                       bidx: Int,
-                       target: Array[Int]): Array[Int] =
+  private def nextHash(
+      valueToHash: A,
+      hashIndex: Int,
+      buffer: Array[Int],
+      bidx: Int,
+      target: Array[Int]
+  ): Array[Int] =
     if (hashIndex == numHashes) target
     else {
       val thisBidx = if (bidx > 3) {