Refine instantiation scheme

odersky · odersky · commit 67954fe24811 · 2017-07-21T08:57:10.000+02:00
Commit only if the adapt following the instantiation is
error-free. DottyLanguageServer had a compilation failure
due to the previous scheme.
diff --git a/compiler/src/dotty/tools/dotc/typer/Typer.scala b/compiler/src/dotty/tools/dotc/typer/Typer.scala
@@ -2191,8 +2191,11 @@ class Typer extends Namer with TypeAssigner with Applications with Implicits wit
         val prevConstraint = localCtx.typerState.constraint
         if (isFullyDefined(wtp, force = ForceDegree.all)(localCtx) &&
             localCtx.typerState.constraint.ne(prevConstraint)) {
-          localCtx.typerState.commit()
-          return adapt(tree, pt, original)
+          val tree1 = adapt(tree, pt, original)(localCtx)
+          if (!localCtx.reporter.hasErrors) {
+            localCtx.typerState.commit()
+            return tree1
+          }
         }
       }
       // try an implicit conversion

Original file line number	Diff line number	Diff line change
`@@ -2191,8 +2191,11 @@ class Typer extends Namer with TypeAssigner with Applications with Implicits wit`
`2191`	`2191`	`val prevConstraint = localCtx.typerState.constraint`
`2192`	`2192`	`if (isFullyDefined(wtp, force = ForceDegree.all)(localCtx) &&`
`2193`	`2193`	`localCtx.typerState.constraint.ne(prevConstraint)) {`
`2194`		`- localCtx.typerState.commit()`
`2195`		`- return adapt(tree, pt, original)`
	`2194`	`+ val tree1 = adapt(tree, pt, original)(localCtx)`
	`2195`	`+ if (!localCtx.reporter.hasErrors) {`
	`2196`	`+ localCtx.typerState.commit()`
	`2197`	`+ return tree1`
	`2198`	`+ }`
`2196`	`2199`	`}`
`2197`	`2200`	`}`
`2198`	`2201`	`// try an implicit conversion`