diff options
| -rw-r--r-- | src/compiler/scala/tools/nsc/typechecker/Infer.scala | 15 | ||||
| -rw-r--r-- | test/files/neg/t5845.check | 5 | ||||
| -rw-r--r-- | test/files/pos/t4881.scala | 31 |
3 files changed, 6 insertions, 45 deletions
diff --git a/src/compiler/scala/tools/nsc/typechecker/Infer.scala b/src/compiler/scala/tools/nsc/typechecker/Infer.scala index 0c3dcb9342..cb5fc8df5a 100644 --- a/src/compiler/scala/tools/nsc/typechecker/Infer.scala +++ b/src/compiler/scala/tools/nsc/typechecker/Infer.scala @@ -517,7 +517,7 @@ trait Infer extends Checkable { val tvars = tparams map freshVar if (isConservativelyCompatible(restpe.instantiateTypeParams(tparams, tvars), pt)) map2(tparams, tvars)((tparam, tvar) => - instantiateToBound(tvar, inferVariance(formals, restpe)(tparam))) + instantiateToBound(tvar, varianceInTypes(formals)(tparam))) else tvars map (tvar => WildcardType) } @@ -647,24 +647,13 @@ trait Infer extends Checkable { "argument expression's type is not compatible with formal parameter type" + foundReqMsg(tp1, pt1)) } } - val targs = solvedTypes( - tvars, tparams, tparams map inferVariance(formals, restpe), + tvars, tparams, tparams map varianceInTypes(formals), false, lubDepth(formals) max lubDepth(argtpes) ) adjustTypeArgs(tparams, tvars, targs, restpe) } - /** Determine which variance to assume for the type paraneter. We first chose the variance - * that minimizes any formal parameters. If that is still undetermined, because the type parameter - * does not appear as a formal parameter type, then we pick the variance so that it minimizes the - * method's result type instead. - */ - private def inferVariance(formals: List[Type], restpe: Type)(tparam: Symbol): Int = { - val v = varianceInTypes(formals)(tparam) - if (v != VarianceFlags) v else varianceInType(restpe)(tparam) - } - private[typechecker] def followApply(tp: Type): Type = tp match { case NullaryMethodType(restp) => val restp1 = followApply(restp) diff --git a/test/files/neg/t5845.check b/test/files/neg/t5845.check index c0b402fccb..8c6100d6de 100644 --- a/test/files/neg/t5845.check +++ b/test/files/neg/t5845.check @@ -1,4 +1,7 @@ +t5845.scala:9: error: value +++ is not a member of Int + println(5 +++ 5) + ^ t5845.scala:15: error: value +++ is not a member of Int println(5 +++ 5) ^ -one error found +two errors found diff --git a/test/files/pos/t4881.scala b/test/files/pos/t4881.scala deleted file mode 100644 index 46cfad9793..0000000000 --- a/test/files/pos/t4881.scala +++ /dev/null @@ -1,31 +0,0 @@ -class Contra[-T] -trait A -trait B extends A -trait C extends B - -// test improved variance inference: first try formals to see in which variance positions the type param appears; -// only when that fails to determine variance, look at result type -object Test { - def contraLBUB[a >: C <: A](): Contra[a] = null - def contraLB[a >: C](): Contra[a] = null - -{ - val x = contraLBUB() //inferred Contra[C] instead of Contra[A] - val x1: Contra[A] = x -} - -{ - val x = contraLB() //inferred Contra[C] instead of Contra[Any] - val x1: Contra[Any] = x -} - -{ - val x = contraLBUB // make sure it does the same thing as its ()-less counterpart - val x1: Contra[A] = x -} - -{ - val x = contraLB - val x1: Contra[Any] = x -} -} |