From 3b69ffa33d419ee31331582edac427393009e711 Mon Sep 17 00:00:00 2001 From: Michael Williamson Date: Mon, 3 Jul 2023 12:30:50 +0100 Subject: Check shadowing behaviour --- .../compiler/typechecker/TypeCheckerValTests.java | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) (limited to 'src/test/java') diff --git a/src/test/java/org/shedlang/compiler/typechecker/TypeCheckerValTests.java b/src/test/java/org/shedlang/compiler/typechecker/TypeCheckerValTests.java index 1526d3aa..7967e442 100644 --- a/src/test/java/org/shedlang/compiler/typechecker/TypeCheckerValTests.java +++ b/src/test/java/org/shedlang/compiler/typechecker/TypeCheckerValTests.java @@ -68,4 +68,24 @@ public class TypeCheckerValTests { assertThat(error.variableName(), equalTo("x")); } + + @Test + public void whenValShadowsExistingVariableThenValCannotBeReferencedBeforeDefinition() { + var untyped = UntypedFunctionDefinitionNode.builder() + .addStatement(Untyped.expressionStatement(Untyped.reference("x"))) + .addStatement(Untyped.val(Untyped.targetVariable("x"), Untyped.stringLiteral("hello"))) + .build(); + var context = TypeCheckerContext.EMPTY + .enterBlockWithDefinedVariables(P.map( + Map.entry("Unit", Types.metaType(Types.UNIT)), + Map.entry("x", Types.INT) + )); + + var error = assertThrows( + ReferenceBeforeDefinitionError.class, + () -> TypeChecker.typeCheckNamespaceStatement(untyped, context) + ); + + assertThat(error.variableName(), equalTo("x")); + } } -- cgit v1.2.3