Tweak tests for inferred implicits

test/async/jvm/toughtype.scala

@@ -199,7 +199,7 @@ package scala.async.run.toughtype {
       }
 
       object FunDep {
-        implicit def `Something to do with List`[W, S, R](implicit funDep: FunDep[W, S, R]) =
+        implicit def `Something to do with List`[W, S, R](implicit funDep: FunDep[W, S, R]): FunDep[W,List[S],W] =
           new FunDep[W, List[S], W] {
             def method(w: W, l: List[S]) = async {
               val it = l.iterator

test/files/jvm/future-spec/main.scala

@@ -17,9 +17,10 @@ object Test {
 }
 
 trait Features {
-  implicit def implicitously = scala.language.implicitConversions
-  implicit def reflectively  = scala.language.reflectiveCalls
-  implicit def postulously   = scala.language.postfixOps
+  import languageFeature._
+  implicit def implicitously: implicitConversions = scala.language.implicitConversions
+  implicit def reflectively: reflectiveCalls      = scala.language.reflectiveCalls
+  implicit def postulously: postfixOps            = scala.language.postfixOps
 }
 
 
@@ -40,7 +41,9 @@ trait MinimalScalaTest extends Output with Features with Vigil {
     if (throwables.nonEmpty) println(buffer.toString)
   }
 
-  implicit def stringops(s: String) = new {
+  type Ops = AnyRef{def should[U](snippets: => U): U; def in[U](snippet: => U): scala.collection.mutable.IndexedSeq[_ >: Char with Throwable] with scala.collection.mutable.AbstractSeq[_ >: Char with Throwable] with scala.collection.mutable.Growable[Char with Throwable] with java.io.Serializable}
+
+  implicit def stringops(s: String): Ops = new {
 
     def should[U](snippets: => U) = {
       bufferPrintln(s + " should:")
@@ -62,7 +65,8 @@ trait MinimalScalaTest extends Output with Features with Vigil {
 
   }
 
-  implicit def objectops(obj: Any) = new {
+  type OOps = AnyRef{def mustBe(other: Any): Unit; def mustEqual(other: Any): Unit}
+  implicit def objectops(obj: Any): OOps = new {
 
     def mustBe(other: Any) = assert(obj == other, s"$obj is not $other")
     def mustEqual(other: Any) = mustBe(other)

test/files/jvm/interpreter.check

@@ -87,6 +87,8 @@ scala> case class Bar(n: Int)
 class Bar
 
 scala> implicit def foo2bar(foo: Foo) = Bar(foo.n)
+                    ^
+       warning: Implicit definition should have explicit type (inferred Bar)
 warning: 1 feature warning; for details, enable `:setting -feature` or `:replay -feature`
 def foo2bar(foo: Foo): Bar
 

test/files/jvm/scala-concurrent-tck.scala

@@ -1055,7 +1055,7 @@ class ExecutionContextPrepare extends TestBase {
       delegate.reportFailure(t)
   }
 
-  implicit val ec = new PreparingExecutionContext
+  implicit val ec: ExecutionContext = new PreparingExecutionContext
 
   def testOnComplete(): Unit = once {
     done =>

test/files/neg/implicit-log.scala

@@ -37,8 +37,8 @@ object Test1579 {
   class Query[E](val value: E)
   class Invoker(q: Any) { val foo = null }
 
-  implicit def unwrap[C](q: Query[C]) = q.value
-  implicit def invoker(q: Query[Column]) = new Invoker(q)
+  implicit def unwrap[C](q: Query[C]): C = q.value
+  implicit def invoker(q: Query[Column]): Invoker = new Invoker(q)
 
   val q = new Query(new Column)
   q.foo
@@ -50,9 +50,9 @@ object Test1625 {
     def unwrap() = x
   }
 
-  implicit def byName[A](x: => A) = new Wrapped(x)
+  implicit def byName[A](x: => A): Wrapped = new Wrapped(x)
 
-  implicit def byVal[A](x: A) = x
+  implicit def byVal[A](x: A): A = x
 
   def main(args: Array[String]) = {
 

test/files/neg/implicits.check

@@ -16,4 +16,11 @@ implicits.scala:47: error: type mismatch;
 implicits.scala:59: error: could not find implicit value for parameter x: Nothing
   foo {
       ^
+implicits.scala:34: warning: Implicit definition should have explicit type (inferred T)
+  implicit def select[T](t: HSome[T,_]) = t.head
+               ^
+implicits.scala:35: warning: Implicit definition should have explicit type (inferred L)
+  implicit def selectTail[L](t: HSome[_,L]) = t.tail
+               ^
+2 warnings
 4 errors

test/files/neg/override-final-implicit.check

@@ -1,5 +1,9 @@
+override-final-implicit.scala:6: warning: Implicit definition should have explicit type (inferred Test.this.FooExtender)
+  override implicit def FooExtender(foo: String) = super.FooExtender(foo)
+                        ^
 override-final-implicit.scala:6: error: cannot override final member:
 final implicit def FooExtender(foo: String): Test.this.FooExtender (defined in class Implicits)
   override implicit def FooExtender(foo: String) = super.FooExtender(foo)
                         ^
+1 warning
 1 error

test/files/neg/private-implicit-class.check

@@ -1,4 +1,8 @@
 private-implicit-class.scala:6: error: method BarExtender in class ImplicitsPrivate cannot be accessed as a member of ImplicitsPrivate from class TestPrivate
   override implicit def BarExtender(bar: Int) = super.BarExtender(bar) // error
                                                       ^
+private-implicit-class.scala:6: warning: Implicit definition should have explicit type
+  override implicit def BarExtender(bar: Int) = super.BarExtender(bar) // error
+                        ^
+1 warning
 1 error

test/files/neg/t1038.scala

@@ -4,5 +4,6 @@ object Y {
   val a = new X
   import a._
   implicit val b : Int = 1
+  @annotation.nowarn
   implicit val c = 2
 }

test/files/neg/t2206.check

@@ -2,4 +2,8 @@ t2206.scala:10: error: value f is not a member of o.A
  Note: implicit method ax is not applicable here because it comes after the application point and it lacks an explicit result type
   a.f()
     ^
+t2206.scala:13: warning: Implicit definition should have explicit type (inferred o.AX)
+      implicit def ax(a: A) = new AX
+                   ^
+1 warning
 1 error

test/files/neg/t2421b.check

@@ -1,4 +1,8 @@
 t2421b.scala:12: error: could not find implicit value for parameter aa: Test.F[Test.A]
   f
   ^
+t2421b.scala:10: warning: Implicit definition should have explicit type (inferred Test.F[X])
+  implicit def b[X <: B] = new F[X]()
+               ^
+1 warning
 1 error

test/files/neg/t2866.scala

@@ -1,7 +1,7 @@
 // for 2.7.x compatibility
 
 object A {
-  implicit val one = 1
+  implicit val one: Int = 1
 }
 
 object Test {

test/files/neg/t3006.check

@@ -3,4 +3,8 @@ t3006.scala:8: error: type mismatch;
  required: Int
   println(A(3) + "H")
                  ^
+t3006.scala:6: warning: Implicit definition should have explicit type (inferred Test.Foo)
+  implicit def aToFoo(x: A) = new Foo(x);
+               ^
+1 warning
 1 error

test/files/neg/t3346c.check

@@ -1,4 +1,4 @@
-t3346c.scala:60: error: value bar is not a member of Either[Int,String]
+t3346c.scala:65: error: value bar is not a member of Either[Int,String]
 did you mean map?
   eii.bar
       ^

test/files/neg/t3346c.scala

@@ -1,3 +1,5 @@
+import annotation._
+
 object Test extends App {
   //
   // An attempt to workaround scala/bug#2712, foiled by scala/bug#3346
@@ -32,15 +34,18 @@ object Test extends App {
   }
 
 
+  @nowarn
   implicit def ToTCValue[M[_], A](ma: M[A])(implicit M0: TC[M]) = new TCValue[M, A] {
-    implicit val M = M0
+    implicit val M: TC[M] = M0
     val self = ma
   }
   implicit def ToTCValueBin1[M[_, _], A, B](ma: M[A, B])(implicit M0: TC[({type λ[α]=M[A, α]})#λ]): TCValue[({type λ[α] = M[A, α]})#λ, B] = new TCValue[({type λ[α]=M[A, α]})#λ, B] {
+    @nowarn
     implicit val M = M0
     val self = ma
   }
   implicit def ToTCValueBin2[M[_, _], A, B](ma: M[A, B])(implicit M0: TC[({type λ[α]=M[α, B]})#λ]): TCValue[({type λ[α]=M[α, B]})#λ, A] = new TCValue[({type λ[α]=M[α, B]})#λ, A] {
+    @nowarn
     implicit val M = M0
     val self = ma
   }

test/files/neg/t3346i.check

@@ -4,4 +4,20 @@ t3346i.scala:28: error: value a is not a member of Test.A[T]
 t3346i.scala:29: error: value a is not a member of Test.A[Nothing]
   (new A[Nothing]).a
                    ^
+t3346i.scala:16: warning: Implicit definition should have explicit type (inferred Implicit1[T])
+  implicit def implicit1[T <: Intermediate[_, _]](implicit b: Implicit2[T])                = new Implicit1[T](b)
+               ^
+t3346i.scala:18: warning: Implicit definition should have explicit type (inferred Implicit2[T])
+  implicit def implicit2alt1[T <: Intermediate[_ <: String, _]](implicit c: Implicit3[T])  = new Implicit2[T](c)
+               ^
+t3346i.scala:19: warning: Implicit definition should have explicit type (inferred Implicit2[T])
+  implicit def implicit2alt2[T <: Intermediate[_ <: Double, _]](implicit c: Implicit3[T])  = new Implicit2[T](c)
+               ^
+t3346i.scala:21: warning: Implicit definition should have explicit type (inferred Implicit3[T])
+  implicit def implicit3alt1[T <: Intermediate[_, _ <: Int]]                               = new Implicit3[T]()
+               ^
+t3346i.scala:22: warning: Implicit definition should have explicit type (inferred Implicit3[T])
+  implicit def implicit3alt2[T <: Intermediate[_ <: Double, _ <: AnyRef],X]                = new Implicit3[T]()
+               ^
+5 warnings
 2 errors

test/files/neg/t4271.check

@@ -8,4 +8,23 @@ t4271.scala:11: error: value -> is not a member of Int
 did you mean >>>?
   3 -> 5
     ^
+t4271.scala:3: warning: Implicit definition should have explicit type (inferred foo.Donotuseme.type)
+  implicit def Ensuring[A](x: A) = Donotuseme
+               ^
+t4271.scala:4: warning: Implicit definition should have explicit type (inferred foo.Donotuseme.type)
+  implicit def doubleWrapper(x: Int) = Donotuseme
+               ^
+t4271.scala:5: warning: Implicit definition should have explicit type (inferred foo.Donotuseme.type)
+  implicit def floatWrapper(x: Int) = Donotuseme
+               ^
+t4271.scala:6: warning: Implicit definition should have explicit type (inferred foo.Donotuseme.type)
+  implicit def intWrapper(x: Int) = Donotuseme
+               ^
+t4271.scala:7: warning: Implicit definition should have explicit type (inferred foo.Donotuseme.type)
+  implicit def longWrapper(x: Int) = Donotuseme
+               ^
+t4271.scala:8: warning: Implicit definition should have explicit type (inferred foo.Donotuseme.type)
+  implicit def ArrowAssoc[A](x: A) = Donotuseme
+               ^
+6 warnings
 3 errors

test/files/neg/t4457_1.check

@@ -4,4 +4,20 @@ and  method aFunc in object ImplicitConvAmbiguity2 of type [A](a: ImplicitConvAm
 match argument types (Float)
     val x = aFunc(4F)
             ^
+t4457_1.scala:11: warning: Implicit definition should have explicit type (inferred ImplicitConvAmbiguity2.NE[Float])
+  implicit def conv1(i: Float) = new NE[Float]
+               ^
+t4457_1.scala:12: warning: Implicit definition should have explicit type (inferred ImplicitConvAmbiguity2.N[java.util.TooManyListenersException])
+  implicit def conv3(op: AA[java.util.TooManyListenersException]) = new N[java.util.TooManyListenersException]
+               ^
+t4457_1.scala:13: warning: Implicit definition should have explicit type (inferred ImplicitConvAmbiguity2.N[Float])
+  implicit def conv4(op: AA[Float]) = new N[Float]
+               ^
+t4457_1.scala:14: warning: Implicit definition should have explicit type (inferred ImplicitConvAmbiguity2.NZ[Float])
+  implicit def conv7(i: Float) = new NZ[Float]
+               ^
+t4457_1.scala:15: warning: Implicit definition should have explicit type (inferred ImplicitConvAmbiguity2.N[java.util.GregorianCalendar])
+  implicit def conv5(e: BB[java.util.GregorianCalendar]) = new N[java.util.GregorianCalendar]
+               ^
+5 warnings
 1 error

test/files/neg/t4457_2.check

@@ -10,4 +10,20 @@ and  method aFunc in object ImplicitConvAmbiguity2 of type [A](a: ImplicitConvAm
 match argument types (Float)
     bFunc(aFunc(4F))
           ^
+t4457_2.scala:11: warning: Implicit definition should have explicit type (inferred ImplicitConvAmbiguity2.NE[Float])
+  implicit def conv1(i: Float) = new NE[Float]
+               ^
+t4457_2.scala:12: warning: Implicit definition should have explicit type (inferred ImplicitConvAmbiguity2.N[java.util.TooManyListenersException])
+  implicit def conv3(op: AA[java.util.TooManyListenersException]) = new N[java.util.TooManyListenersException]
+               ^
+t4457_2.scala:13: warning: Implicit definition should have explicit type (inferred ImplicitConvAmbiguity2.N[Float])
+  implicit def conv4(op: AA[Float]) = new N[Float]
+               ^
+t4457_2.scala:14: warning: Implicit definition should have explicit type (inferred ImplicitConvAmbiguity2.NZ[Float])
+  implicit def conv7(i: Float) = new NZ[Float]
+               ^
+t4457_2.scala:15: warning: Implicit definition should have explicit type (inferred ImplicitConvAmbiguity2.N[java.util.GregorianCalendar])
+  implicit def conv5(e: BB[java.util.GregorianCalendar]) = new N[java.util.GregorianCalendar]
+               ^
+5 warnings
 2 errors

test/files/neg/t4568.check

@@ -1,4 +1,8 @@
 t4568.scala:8: error: recursive method isSubListOf needs result type
         case h :: t => y.contains(h) && (t.isSubListOf(y.drop(y.indexOf(h) + 1)))
                                            ^
+t4568.scala:2: warning: Implicit definition should have explicit type (inferred SubList.SubListable[A])
+  implicit def sublistable[A](x: List[A]) = new SubListable(x)
+               ^
+1 warning
 1 error

test/files/neg/t4889.check

@@ -1,4 +1,8 @@
 t4889.scala:19: error: could not find implicit value for parameter ma1: t4889.MatrixAdder[Int,[S]t4889.SparseMatrix[S]]
   m1.foo
      ^
+t4889.scala:14: warning: Implicit definition should have explicit type (inferred t4889.MatrixAdder[S,R])
+  implicit def adderImplicit[S, R[s] <: Matrix[s, R]] = new MatrixAdder[S, R] {
+               ^
+1 warning
 1 error

test/files/neg/t5728.check

@@ -1,4 +1,8 @@
 t5728.scala:3: error: implicit classes must accept exactly one primary constructor parameter
   implicit class Foo
                  ^
+t5728.scala:5: warning: Implicit definition should have explicit type (inferred Test.Foo)
+  implicit def Foo = new Foo
+               ^
+1 warning
 1 error

test/files/neg/t6436.check

@@ -7,4 +7,11 @@ Note that implicit conversions are not applicable because they are ambiguous:
  are possible conversion functions from StringContext to ?{def q: ?}
   println(q"a")
           ^
+t6436.scala:2: warning: Implicit definition should have explicit type (inferred AnyRef{def q: Nothing})
+  implicit def foo1(ctx: StringContext) = new { def q = ??? }
+               ^
+t6436.scala:3: warning: Implicit definition should have explicit type (inferred AnyRef{def q: Nothing})
+  implicit def foo2(ctx: StringContext) = new { def q = ??? }
+               ^
+2 warnings
 1 error

test/files/neg/t6436b.check

@@ -7,4 +7,11 @@ Note that implicit conversions are not applicable because they are ambiguous:
  are possible conversion functions from StringContext to ?{def q: ?}
   println(StringContext("a").q())
                        ^
+t6436b.scala:2: warning: Implicit definition should have explicit type (inferred AnyRef{def q: Nothing})
+  implicit def foo1(ctx: StringContext) = new { def q = ??? }
+               ^
+t6436b.scala:3: warning: Implicit definition should have explicit type (inferred AnyRef{def q: Nothing})
+  implicit def foo2(ctx: StringContext) = new { def q = ??? }
+               ^
+2 warnings
 1 error

test/files/neg/t6567.check

@@ -1,3 +1,6 @@
+t6567.scala:8: warning: Implicit definition should have explicit type (inferred B)
+  implicit def a2b(a: A) = new B
+               ^
 t6567.scala:10: warning: Suspicious application of an implicit view (Test.this.a2b) in the argument to Option.apply.
   Option[B](a)
            ^
@@ -6,5 +9,5 @@ t6567.scala:12: warning: Suspicious application of an implicit view (Test.this.a
                            ^
 warning: 1 feature warning; re-run with -feature for details
 error: No warnings can be incurred under -Werror.
-3 warnings
+4 warnings
 1 error

test/files/neg/t6667.check

@@ -10,4 +10,8 @@ t6667.scala:9: error: ambiguous implicit values:
  match expected type C
   implicitly[C]       // ambiguity reported, rather than falling back to C.companion
             ^
+t6667.scala:3: warning: Implicit definition should have explicit type (inferred C)
+  implicit def companion = new C
+               ^
+1 warning
 2 errors

test/files/neg/t6667.scala

@@ -4,7 +4,7 @@ object C {
 }
 
 object Test {
-  implicit val inScope1, inScope2 = new C
+  implicit val inScope1, inScope2: C = new C
   implicitly[C]: Unit // C.companion was used; whereas the ambiguity should abort the implicit search.
   implicitly[C]       // ambiguity reported, rather than falling back to C.companion
 }

test/files/neg/t692.check

@@ -16,4 +16,8 @@ t692.scala:14: error: class Foo takes type parameters
 t692.scala:19: error: class Foo takes type parameters
   class Bar[A <: Foo](implicit tpeA : Type[A]) extends Foo;
                  ^
+t692.scala:11: warning: Implicit definition should have explicit type (inferred test3.this.FooType)
+  implicit def typeOfFoo = FooType();
+               ^
+1 warning
 6 errors

test/files/neg/t712.check

@@ -1,4 +1,11 @@
 t712.scala:10: error: overloaded method coerce needs result type
   implicit def coerce(p : ParentImpl) = p.self;
                                           ^
+t712.scala:3: warning: Implicit definition should have explicit type (inferred A.this.Node)
+  implicit def coerce(n : NodeImpl) = n.self;
+               ^
+t712.scala:10: warning: Implicit definition should have explicit type
+  implicit def coerce(p : ParentImpl) = p.self;
+               ^
+2 warnings
 1 error

test/files/neg/t7131.check

@@ -4,4 +4,11 @@ t7131.scala:21: error: type mismatch;
  Note: implicit method convertToSimpleMappable is not applicable here because it comes after the application point and it lacks an explicit result type
         x.value.map(f)
                    ^
+t7131.scala:28: warning: Implicit definition should have explicit type (inferred ObservableValue.TraversableMappable[T,Container])
+  implicit def convertToTraversableMappable[T, Container[X] <: Traversable[X]](x: ObservableValue[Container[T]]) =
+               ^
+t7131.scala:43: warning: Implicit definition should have explicit type (inferred ObservableValue.NestedMappable[T,Container])
+  implicit def convertToSimpleMappable[T, Container[X] <: ObservableValue.HasMap[X, Container]](x: ObservableValue[Container[T]]) =
+               ^
+2 warnings
 1 error