Merge pull request #7773 from dotty-staging/fix-#7750

Fix #7750: Circumvent an assertion failure for erroneous code

Author: smarter

compiler/src/dotty/tools/dotc/typer/Checking.scala

@@ -716,9 +716,9 @@ trait Checking {
   def checkImplicitConversionUseOK(sym: Symbol, posd: Positioned)(implicit ctx: Context): Unit =
     if (sym.exists) {
       val conv =
-        if (sym.isOneOf(GivenOrImplicit)) sym
+        if (sym.isOneOf(GivenOrImplicit) || sym.info.isErroneous) sym
         else {
-          assert(sym.name == nme.apply)
+          assert(sym.name == nme.apply || ctx.reporter.errorsReported)
           sym.owner
         }
       val conversionOK =

tests/neg/i7750.scala

@@ -0,0 +1,3 @@
+package object A extends runtime.A {
+    implicit def a( : ) = 1() // error // error // error
+}

tests/neg/i7750a.scala

@@ -0,0 +1,5 @@
+def foo: Unit = {
+    val a = (x: Int, y: String) => x + + y  // error
+    implicit def f[X](x: (X,  String) => String) = (z: X) => (z, null) // error
+    a(1)
+}