diff options
| -rw-r--r-- | src/dotty/tools/dotc/typer/RefChecks.scala | 14 | ||||
| -rw-r--r-- | test/dotc/tests.scala | 1 | ||||
| -rw-r--r-- | tests/neg/valueClasses.scala | 10 |
3 files changed, 24 insertions, 1 deletions
diff --git a/src/dotty/tools/dotc/typer/RefChecks.scala b/src/dotty/tools/dotc/typer/RefChecks.scala index 067694bfd..bb411c6b5 100644 --- a/src/dotty/tools/dotc/typer/RefChecks.scala +++ b/src/dotty/tools/dotc/typer/RefChecks.scala @@ -708,7 +708,19 @@ object RefChecks { if (clazz.is(Abstract)) ctx.error("`abstract' modifier cannot be used with value classes", clazz.pos) if (!clazz.isStatic) - ctx.error("value class cannot be an inner class", clazz.pos) + ctx.error(s"value class may not be a ${if (clazz.owner.isTerm) "local class" else "member of another class"}", clazz.pos) + else { + val clParamAccessors = clazz.asClass.paramAccessors.filter(sym => sym.isTerm && !sym.is(Method)) + clParamAccessors match { + case List(param) => + if (param.is(Mutable)) + ctx.error("value class parameter must not be a var", param.pos) + if (param.is(PrivateLocal)) + ctx.error("value class parameter must not be private[this]", param.pos) + case _ => + ctx.error("value class needs to have exactly one val parameter", clazz.pos) + } + } stats.foreach(checkValueClassMember) } } diff --git a/test/dotc/tests.scala b/test/dotc/tests.scala index 12b830738..70af32bd3 100644 --- a/test/dotc/tests.scala +++ b/test/dotc/tests.scala @@ -185,6 +185,7 @@ class tests extends CompilerTest { @Test def neg_validateRefchecks = compileFile(negDir, "validate-refchecks", xerrors = 2) @Test def neg_skolemize = compileFile(negDir, "skolemize", xerrors = 2) @Test def neg_nested_bounds = compileFile(negDir, "nested_bounds", xerrors = 1) + @Test def neg_valueClasses = compileFile(negDir, "valueClasses", xerrors = 4) @Test def run_all = runFiles(runDir) diff --git a/tests/neg/valueClasses.scala b/tests/neg/valueClasses.scala new file mode 100644 index 000000000..ae90ef63c --- /dev/null +++ b/tests/neg/valueClasses.scala @@ -0,0 +1,10 @@ +class A1 { + class A2(x: Int) extends AnyVal // error: value class may not be a member of another class +} +class B1 { + def test = { + class B2(x: Int) extends AnyVal // error: value class may not be a local class + } +} +class C(private[this] val u: Int) extends AnyVal // error: value class parameter must not be private[this] +class D(u: Int) extends AnyVal // error: value class parameter must not be private[this] |