fix: disallow toplevel infix definitions for vals, vars, givens, meth…

…ods and implicits Part of scala#17738
arainko · Jun 17, 2023 · ed64113 · ed64113
1 parent 2d9eb1c
commit ed64113
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Showing 5 changed files with 46 additions and 0 deletions.
diff --git a/compiler/src/dotty/tools/dotc/reporting/ErrorMessageID.scala b/compiler/src/dotty/tools/dotc/reporting/ErrorMessageID.scala
@@ -196,6 +196,7 @@ enum ErrorMessageID(val isActive: Boolean = true) extends java.lang.Enum[ErrorMe
   case AmbiguousExtensionMethodID // errorNumber 180
   case UnqualifiedCallToAnyRefMethodID // errorNumber: 181
   case NotConstantID // errorNumber: 182
+  case ToplevelDefCantBeInfixID // errorNumber: 183
 
   def errorNumber = ordinal - 1
 

diff --git a/compiler/src/dotty/tools/dotc/reporting/messages.scala b/compiler/src/dotty/tools/dotc/reporting/messages.scala
@@ -2913,3 +2913,13 @@ class MatchTypeScrutineeCannotBeHigherKinded(tp: Type)(using Context)
   extends TypeMsg(MatchTypeScrutineeCannotBeHigherKindedID) :
     def msg(using Context) = i"the scrutinee of a match type cannot be higher-kinded"
     def explain(using Context) = ""
+
+class ToplevelDefCantBeInfix(sym: Symbol)(using Context)
+  extends SyntaxMsg(ToplevelDefCantBeInfixID):
+    def msg(using Context) = i"a toplevel $defName cannot be infix"
+    def explain(using Context) = ""
+    private val defName = 
+      if sym.flags.is(Method) then "def"
+      else if sym.flags.is(Mutable) then "var"
+      else if sym.flags.is(Given) then "given"
+      else "val"
diff --git a/compiler/src/dotty/tools/dotc/typer/Checking.scala b/compiler/src/dotty/tools/dotc/typer/Checking.scala
@@ -555,6 +555,7 @@ object Checking {
         fail(CannotHaveSameNameAs(sym, cls, CannotHaveSameNameAs.CannotBeOverridden))
         sym.setFlag(Private) // break the overriding relationship by making sym Private
       }
+    if sym.isWrappedToplevelDef && !sym.isType then fail(ToplevelDefCantBeInfix(sym))
     checkApplicable(Erased,
       !sym.isOneOf(MutableOrLazy, butNot = Given) && !sym.isType || sym.isClass)
     checkCombination(Final, Open)

diff --git a/tests/neg/i17738-toplevel-infix.check b/tests/neg/i17738-toplevel-infix.check
@@ -0,0 +1,20 @@
+-- [E183] Syntax Error: tests/neg/i17738-toplevel-infix.scala:10:10 ----------------------------------------------------
+10 |infix val toplevelVal = ??? // error
+   |          ^
+   |          a toplevel val cannot be infix
+-- [E183] Syntax Error: tests/neg/i17738-toplevel-infix.scala:11:10 ----------------------------------------------------
+11 |infix var toplevelVar = ??? // error
+   |          ^
+   |          a toplevel var cannot be infix
+-- [E183] Syntax Error: tests/neg/i17738-toplevel-infix.scala:12:10 ----------------------------------------------------
+12 |infix def toplevelDef = ??? // error
+   |          ^
+   |          a toplevel def cannot be infix
+-- [E183] Syntax Error: tests/neg/i17738-toplevel-infix.scala:13:12 ----------------------------------------------------
+13 |infix given toplevelGiven: Int = ??? // error
+   |            ^
+   |            a toplevel given cannot be infix
+-- [E183] Syntax Error: tests/neg/i17738-toplevel-infix.scala:14:19 ----------------------------------------------------
+14 |infix implicit val topevelImplicit: Int = ??? // error
+   |                   ^
+   |                   a toplevel val cannot be infix
diff --git a/tests/neg/i17738-toplevel-infix.scala b/tests/neg/i17738-toplevel-infix.scala
@@ -0,0 +1,14 @@
+infix type A[b, a] = Nothing
+
+infix type B[b, a] = b match {
+  case Int => a
+}
+
+infix class C[A, B]
+infix trait D[A, B]
+
+infix val toplevelVal = ??? // error
+infix var toplevelVar = ??? // error
+infix def toplevelDef = ??? // error
+infix given toplevelGiven: Int = ??? // error
+infix implicit val topevelImplicit: Int = ??? // error