Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Matching against an extractor with no arguments crashes the compiler #5078

Closed
scabug opened this issue Oct 15, 2011 · 2 comments
Closed

Matching against an extractor with no arguments crashes the compiler #5078

scabug opened this issue Oct 15, 2011 · 2 comments
Assignees

Comments

@scabug
Copy link

scabug commented Oct 15, 2011

Define an extractor object that has a no-args unapply method, then try to match against it. Whatever expression you write on the left-hand side of the match (even if this expression refers to not declared symbols!), the compiler will crash.as follows:

scala> object Foo { def unapply(): Option[Int] = Some(42) }
defined module Foo

scala> val Foo(x) = WHATEVER
<console>:11: error: not found: value WHATEVER
       val Foo(x) = WHATEVER
                    ^
scala.MatchError: ()Option[Int] (of class scala.tools.nsc.symtab.Types$MethodType)
	at scala.tools.nsc.typechecker.Typers$Typer.freshArgType$1(Typers.scala:2510)
	at scala.tools.nsc.typechecker.Typers$Typer.doTypedApply(Typers.scala:2528)
	at scala.tools.nsc.typechecker.Typers$Typer.doTypedApply(Typers.scala:2500)
	at scala.tools.nsc.typechecker.Typers$Typer.typedApply$1(Typers.scala:3371)
	at scala.tools.nsc.typechecker.Typers$Typer.typed1(Typers.scala:4104)
	at scala.tools.nsc.typechecker.Typers$Typer.typed(Typers.scala:4271)
	at scala.tools.nsc.typechecker.Typers$Typer$$anonfun$typedPattern$1.apply(Typers.scala:4369)
	at scala.tools.nsc.typechecker.Typers$Typer$$anonfun$typedPattern$1.apply(Typers.scala:4369)
	at scala.tools.nsc.typechecker.Contexts$Context.withImplicitsDisabled(Contexts.scala:156)
	at scala.tools.nsc.typechecker.Typers$Typer.typedPattern(Typers.scala:4369)
	at scala.tools.nsc.typechecker.Typers$Typer.typedCase(Typers.scala:1941)
	at scala.tools.nsc.typechecker.Typers$Typer$$anonfun$typedCases$1.apply(Typers.scala:1975)
	at scala.tools.nsc.typechecker.Typers$Typer$$anonfun$typedCases$1.apply(Typers.scala:1974)
	at scala.collection.immutable.List.loop$1(List.scala:117)
	at scala.collection.immutable.List.mapConserve(List.scala:133)
	at scala.tools.nsc.typechecker.Typers$Typer.typedCases(Typers.scala:1974)
	at scala.tools.nsc.typechecker.Typers$Typer.typed1(Typers.scala:4003)
	at scala.tools.nsc.typechecker.Typers$Typer.typed(Typers.scala:4271)
	at scala.tools.nsc.typechecker.Typers$Typer.typed(Typers.scala:4344)
	at scala.tools.nsc.typechecker.Typers$Typer.computeType(Typers.scala:4421)
	at scala.tools.nsc.typechecker.Namers$Namer.typeSig(Namers.scala:1207)
	at scala.tools.nsc.typechecker.Namers$Namer$$anonfun$typeCompleter$1.apply(Namers.scala:551)
	at scala.tools.nsc.typechecker.Namers$Namer$$anonfun$typeCompleter$1.apply(Namers.scala:549)
	at scala.tools.nsc.typechecker.Namers$$anon$1.complete(Namers.scala:1385)
	at scala.tools.nsc.typechecker.Namers$$anon$1.complete(Namers.scala:1381)
	at scala.tools.nsc.symtab.Symbols$Symbol.info(Symbols.scala:727)
	at scala.tools.nsc.symtab.Symbols$Symbol.initialize(Symbols.scala:839)
	at scala.tools.nsc.symtab.Symbols$Symbol.annotations(Symbols.scala:73)
	at scala.tools.nsc.typechecker.Typers$Typer.addGetterSetter(Typers.scala:1342)
	at scala.tools.nsc.typechecker.Typers$Typer$$anonfun$13.apply(Typers.scala:1510)
	at scala.tools.nsc.typechecker.Typers$Typer$$anonfun$13.apply(Typers.scala:1510)
	at scala.collection.TraversableLike$$anonfun$flatMap$1.apply(TraversableLike.scala:200)
	at scala.collection.TraversableLike$$anonfun$flatMap$1.apply(TraversableLike.scala:200)
	at scala.collection.LinearSeqOptimized$class.foreach(LinearSeqOptimized.scala:59)
	at scala.collection.immutable.List.foreach(List.scala:45)
	at scala.collection.TraversableLike$class.flatMap(TraversableLike.scala:200)
	at scala.collection.immutable.List.flatMap(List.scala:45)
	at scala.tools.nsc.typechecker.Typers$Typer.typedTemplate(Typers.scala:1510)
	at scala.tools.nsc.typechecker.Typers$Typer.typedModuleDef(Typers.scala:1320)
	at scala.tools.nsc.typechecker.Typers$Typer.typed1(Typers.scala:3913)
	at scala.tools.nsc.typechecker.Typers$Typer.typed(Typers.scala:4271)
	at scala.tools.nsc.typechecker.Typers$Typer.typedStat$1(Typers.scala:2100)
	at scala.tools.nsc.typechecker.Typers$Typer$$anonfun$24.apply(Typers.scala:2184)
	at scala.tools.nsc.typechecker.Typers$Typer$$anonfun$24.apply(Typers.scala:2184)
	at scala.collection.immutable.List.loop$1(List.scala:117)
	at scala.collection.immutable.List.mapConserve(List.scala:133)
	at scala.tools.nsc.typechecker.Typers$Typer.typedStats(Typers.scala:2184)
	at scala.tools.nsc.typechecker.Typers$Typer.typedTemplate(Typers.scala:1512)
	at scala.tools.nsc.typechecker.Typers$Typer.typedModuleDef(Typers.scala:1320)
	at scala.tools.nsc.typechecker.Typers$Typer.typed1(Typers.scala:3913)
	at scala.tools.nsc.typechecker.Typers$Typer.typed(Typers.scala:4271)
	at scala.tools.nsc.typechecker.Typers$Typer.typedStat$1(Typers.scala:2100)
	at scala.tools.nsc.typechecker.Typers$Typer$$anonfun$24.apply(Typers.scala:2184)
	at scala.tools.nsc.typechecker.Typers$Typer$$anonfun$24.apply(Typers.scala:2184)
	at scala.collection.immutable.List.loop$1(List.scala:117)
	at scala.collection.immutable.List.mapConserve(List.scala:133)
	at scala.tools.nsc.typechecker.Typers$Typer.typedStats(Typers.scala:2184)
	at scala.tools.nsc.typechecker.Typers$Typer.typedTemplate(Typers.scala:1512)
	at scala.tools.nsc.typechecker.Typers$Typer.typedModuleDef(Typers.scala:1320)
	at scala.tools.nsc.typechecker.Typers$Typer.typed1(Typers.scala:3913)
	at scala.tools.nsc.typechecker.Typers$Typer.typed(Typers.scala:4271)
	at scala.tools.nsc.typechecker.Typers$Typer.typedStat$1(Typers.scala:2100)
	at scala.tools.nsc.typechecker.Typers$Typer$$anonfun$24.apply(Typers.scala:2184)
	at scala.tools.nsc.typechecker.Typers$Typer$$anonfun$24.apply(Typers.scala:2184)
	at scala.collection.immutable.List.loop$1(List.scala:117)
	at scala.collection.immutable.List.mapConserve(List.scala:133)
	at scala.tools.nsc.typechecker.Typers$Typer.typedStats(Typers.scala:2184)
	at scala.tools.nsc.typechecker.Typers$Typer.typedTemplate(Typers.scala:1512)
	at scala.tools.nsc.typechecker.Typers$Typer.typedModuleDef(Typers.scala:1320)
	at scala.tools.nsc.typechecker.Typers$Typer.typed1(Typers.scala:3913)
	at scala.tools.nsc.typechecker.Typers$Typer.typed(Typers.scala:4271)
	at scala.tools.nsc.typechecker.Typers$Typer.typedStat$1(Typers.scala:2100)
	at scala.tools.nsc.typechecker.Typers$Typer$$anonfun$24.apply(Typers.scala:2184)
	at scala.tools.nsc.typechecker.Typers$Typer$$anonfun$24.apply(Typers.scala:2184)
	at scala.collection.immutable.List.loop$1(List.scala:117)
	at scala.collection.immutable.List.mapConserve(List.scala:133)
	at scala.tools.nsc.typechecker.Typers$Typer.typedStats(Typers.scala:2184)
	at scala.tools.nsc.typechecker.Typers$Typer.typed1(Typers.scala:3906)
	at scala.tools.nsc.typechecker.Typers$Typer.typed(Typers.scala:4271)
	at scala.tools.nsc.typechecker.Typers$Typer.typed(Typers.scala:4331)
	at scala.tools.nsc.typechecker.Analyzer$typerFactory$$anon$3.apply(Analyzer.scala:94)
	at scala.tools.nsc.Global$GlobalPhase.applyPhase(Global.scala:329)
	at scala.tools.nsc.typechecker.Analyzer$typerFactory$$anon$3$$anonfun$run$1.apply(Analyzer.scala:86)
	at scala.tools.nsc.typechecker.Analyzer$typerFactory$$anon$3$$anonfun$run$1.apply(Analyzer.scala:86)
	at scala.collection.Iterator$class.foreach(Iterator.scala:660)
	at scala.collection.mutable.ListBuffer$$anon$1.foreach(ListBuffer.scala:316)
	at scala.tools.nsc.typechecker.Analyzer$typerFactory$$anon$3.run(Analyzer.scala:86)
	at scala.tools.nsc.Global$Run.compileSources(Global.scala:953)
	at scala.tools.nsc.interpreter.IMain$ReadEvalPrint.compileAndSaveRun(IMain.scala:756)
	at scala.tools.nsc.interpreter.IMain$ReadEvalPrint.compile(IMain.scala:731)
	at scala.tools.nsc.interpreter.IMain$Request.compile(IMain.scala:873)
	at scala.tools.nsc.interpreter.IMain.interpret(IMain.scala:576)
	at scala.tools.nsc.interpreter.IMain.interpret(IMain.scala:543)
	at scala.tools.nsc.interpreter.ILoop.reallyInterpret$1(ILoop.scala:694)
	at scala.tools.nsc.interpreter.ILoop.interpretStartingWith(ILoop.scala:745)
	at scala.tools.nsc.interpreter.ILoop.command(ILoop.scala:651)
	at scala.tools.nsc.interpreter.ILoop.processLine$1(ILoop.scala:542)
	at scala.tools.nsc.interpreter.ILoop.loop(ILoop.scala:550)
	at scala.tools.nsc.interpreter.ILoop.process(ILoop.scala:822)
	at scala.tools.nsc.MainGenericRunner.runTarget$1(MainGenericRunner.scala:67)
	at scala.tools.nsc.MainGenericRunner.process(MainGenericRunner.scala:80)
	at scala.tools.nsc.MainGenericRunner$.main(MainGenericRunner.scala:89)
	at scala.tools.nsc.MainGenericRunner.main(MainGenericRunner.scala)
@scabug
Copy link
Author

scabug commented Oct 15, 2011

Imported From: https://issues.scala-lang.org/browse/SI-5078?orig=1
Reporter: Eugene Burmako (xeno.by)

@scabug
Copy link
Author

scabug commented Oct 15, 2011

Commit Message Bot (anonymous) said:
(extempore in r25834) Harden the typer against surprise unapply types.

Closes #5078, no review.

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Labels
None yet
Projects
None yet
Development

No branches or pull requests

2 participants