Merge pull request #6163 from milessabin/topic/i6058

odersky · web-flow · commit 81732c0f60de · 2019-03-25T20:11:30.000+01:00
Use correct type equality in divergence check
diff --git a/compiler/src/dotty/tools/dotc/typer/Implicits.scala b/compiler/src/dotty/tools/dotc/typer/Implicits.scala
@@ -1382,7 +1382,7 @@ abstract class SearchHistory { outer =>
             val wideTp = tp.widenExpr
             lazy val wildTp = wildApprox(wideTp)
             if (belowByname && (wildTp <:< wildPt)) false
-            else if ((wideTp.typeSize < ptSize && wideTp.coveringSet == ptCoveringSet) || (wildTp == wildPt)) true
+            else if ((wideTp.typeSize < ptSize && wideTp.coveringSet == ptCoveringSet) || (wildTp =:= wildPt)) true
             else loop(tl, isByname(tp) || belowByname)
           }
           else loop(tl, isByname(tp) || belowByname)
diff --git a/tests/neg/i6058.scala b/tests/neg/i6058.scala
@@ -0,0 +1,3 @@
+object Test {
+  implicit def i1[I2, I3](i4: I2)(implicit i5: I2 => I3): I3 = ( ) // error
+}

Original file line number	Diff line number	Diff line change
`@@ -1382,7 +1382,7 @@ abstract class SearchHistory { outer =>`
`1382`	`1382`	`val wideTp = tp.widenExpr`
`1383`	`1383`	`lazy val wildTp = wildApprox(wideTp)`
`1384`	`1384`	`if (belowByname && (wildTp <:< wildPt)) false`
`1385`		`- else if ((wideTp.typeSize < ptSize && wideTp.coveringSet == ptCoveringSet) \|\| (wildTp == wildPt)) true`
	`1385`	`+ else if ((wideTp.typeSize < ptSize && wideTp.coveringSet == ptCoveringSet) \|\| (wildTp =:= wildPt)) true`
`1386`	`1386`	`else loop(tl, isByname(tp) \|\| belowByname)`
`1387`	`1387`	`}`
`1388`	`1388`	`else loop(tl, isByname(tp) \|\| belowByname)`
Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,3 @@`
	`1`	`+object Test {`
	`2`	`+ implicit def i1[I2, I3](i4: I2)(implicit i5: I2 => I3): I3 = ( ) // error`
	`3`	`+}`