Avoid NoMatchError in IDE

odersky · odersky · commit c77f26e4eb2b · 2018-02-27T18:24:52.000+01:00
I observed a NoType when editing some code which caused ThisType#underlying to crash.
diff --git a/compiler/src/dotty/tools/dotc/core/Types.scala b/compiler/src/dotty/tools/dotc/core/Types.scala
@@ -2195,7 +2195,7 @@ object Types {
       if (ctx.erasedTypes) tref
       else cls.info match {
         case cinfo: ClassInfo => cinfo.selfType
-        case cinfo: ErrorType if ctx.mode.is(Mode.Interactive) => cinfo
+        case _: ErrorType | NoType if ctx.mode.is(Mode.Interactive) => cls.info
           // can happen in IDE if `cls` is stale
       }
 

Original file line number	Diff line number	Diff line change
`@@ -2195,7 +2195,7 @@ object Types {`
`2195`	`2195`	`if (ctx.erasedTypes) tref`
`2196`	`2196`	`else cls.info match {`
`2197`	`2197`	`case cinfo: ClassInfo => cinfo.selfType`
`2198`		`- case cinfo: ErrorType if ctx.mode.is(Mode.Interactive) => cinfo`
	`2198`	`+ case _: ErrorType \| NoType if ctx.mode.is(Mode.Interactive) => cls.info`
`2199`	`2199`	// can happen in IDE if `cls` is stale
`2200`	`2200`	`}`
`2201`	`2201`