Refactor use of SearchFailure in implicits.

Introduces AmbiguousSearchFailure to go with the
the existing SearchFailure, and changes predicates
to use `SearchResult.{isFailure, isSuccess}`.

This doesn't change behaviour; it is a preparatory
commit for SI-6667.

1 files changed, 2 insertions, 2 deletions

diff --git a/src/compiler/scala/tools/nsc/typechecker/Typers.scala b/src/compiler/scala/tools/nsc/typechecker/Typers.scala
index 222c9ff8c3..70fbc90ce3 100644
--- a/src/compiler/scala/tools/nsc/typechecker/Typers.scala
+++ b/src/compiler/scala/tools/nsc/typechecker/Typers.scala
@@ -132,7 +132,7 @@ trait Typers extends Modes with Adaptations with Tags {
           val res = if (paramFailed || (paramTp.isError && {paramFailed = true; true})) SearchFailure else inferImplicit(fun, paramTp, context.reportErrors, false, context)
           argResultsBuff += res
 
-          if (res != SearchFailure) {
+          if (res.isSuccess) {
             argBuff += mkArg(res.tree, param.name)
           } else {
             mkArg = mkNamedArg // don't pass the default argument (if any) here, but start emitting named arguments for the following args
@@ -761,7 +761,7 @@ trait Typers extends Modes with Adaptations with Tags {
           featureTrait.owner.ownerChain.takeWhile(_ != languageFeatureModule.moduleClass).reverse
         val featureName = (nestedOwners map (_.name + ".")).mkString + featureTrait.name
         def action(): Boolean = {
-          def hasImport = inferImplicit(EmptyTree: Tree, featureTrait.tpe, true, false, context) != SearchFailure
+          def hasImport = inferImplicit(EmptyTree: Tree, featureTrait.tpe, true, false, context).isSuccess
           def hasOption = settings.language.value exists (s => s == featureName || s == "_")
           val OK = hasImport || hasOption
           if (!OK) {