Check named arg is not passed twice

1 files changed, 25 insertions, 4 deletions

diff --git a/src/test/java/org/shedlang/compiler/typechecker/TypeCheckerCallTests.java b/src/test/java/org/shedlang/compiler/typechecker/TypeCheckerCallTests.java
index c46587c3..19c08b14 100644
--- a/src/test/java/org/shedlang/compiler/typechecker/TypeCheckerCallTests.java
+++ b/src/test/java/org/shedlang/compiler/typechecker/TypeCheckerCallTests.java
@@ -2,10 +2,7 @@ package org.shedlang.compiler.typechecker;
 
 import org.junit.jupiter.api.Test;
 import org.shedlang.compiler.ast.untyped.Untyped;
-import org.shedlang.compiler.typechecker.errors.MissingNamedArgError;
-import org.shedlang.compiler.typechecker.errors.UnexpectedNamedArgError;
-import org.shedlang.compiler.typechecker.errors.UnexpectedTypeError;
-import org.shedlang.compiler.typechecker.errors.WrongNumberOfPositionalArgsError;
+import org.shedlang.compiler.typechecker.errors.*;
 import org.shedlang.compiler.typechecker.typesets.TypeSets;
 import org.shedlang.compiler.types.FunctionType;
 import org.shedlang.compiler.types.Types;
@@ -231,4 +228,28 @@ public class TypeCheckerCallTests {
 
         assertThat(error.argName(), equalTo("x"));
     }
+
+    @Test
+    public void whenTwoNamedArgumentsHaveSameNameThenErrorIsThrown() {
+        var untyped = Untyped.call(
+            Untyped.reference("f"),
+            List.of(),
+            List.of(
+                Untyped.namedArg("x", Untyped.stringLiteral("hello")),
+                Untyped.namedArg("x", Untyped.stringLiteral("world"))
+            )
+        );
+        var functionType = FunctionType.builder()
+            .addNamedParam("x", Types.STRING)
+            .build();
+        var context = TypeCheckerContext.EMPTY
+            .enter(P.map(Map.entry("f", functionType)));
+
+        var error = assertThrows(
+            CannotPassNamedArgTwiceError.class,
+            () -> TypeChecker.typeCheckExpression(untyped, context)
+        );
+
+        assertThat(error.argName(), equalTo("x"));
+    }
 }