Type check integer addition

3 files changed, 49 insertions, 0 deletions

diff --git a/src/test/java/org/shedlang/compiler/ast/typed/TypedNodeMatchers.java b/src/test/java/org/shedlang/compiler/ast/typed/TypedNodeMatchers.java
index 4143a91a..69acee24 100644
--- a/src/test/java/org/shedlang/compiler/ast/typed/TypedNodeMatchers.java
+++ b/src/test/java/org/shedlang/compiler/ast/typed/TypedNodeMatchers.java
@@ -40,6 +40,18 @@ public class TypedNodeMatchers {
         return TypedFunctionDefinitionNodeMatcher.empty();
     }
 
+    public static Matcher<TypedExpressionNode> isTypedIntAddNode(
+        Matcher<TypedExpressionNode> left,
+        Matcher<TypedExpressionNode> right
+    ) {
+        return instanceOf(
+            TypedBinaryOperationNode.class,
+            has("operator", x -> x.operator(), equalTo(TypedBinaryOperator.INT_ADD)),
+            has("left", x -> x.left(), left),
+            has("right", x -> x.right(), right)
+        );
+    }
+
     public static Matcher<TypedExpressionNode> isTypedIntLiteralNode(int value) {
         return isTypedIntLiteralNode(BigInteger.valueOf(value));
     }
diff --git a/src/test/java/org/shedlang/compiler/ast/untyped/Untyped.java b/src/test/java/org/shedlang/compiler/ast/untyped/Untyped.java
index ed78e1d4..a5a61303 100644
--- a/src/test/java/org/shedlang/compiler/ast/untyped/Untyped.java
+++ b/src/test/java/org/shedlang/compiler/ast/untyped/Untyped.java
@@ -10,6 +10,18 @@ public class Untyped {
     private Untyped() {
     }
 
+    public static UntypedBinaryOperationNode add(
+        UntypedExpressionNode left,
+        UntypedExpressionNode right
+    ) {
+        return new UntypedBinaryOperationNode(
+            UntypedBinaryOperator.ADD,
+            left,
+            right,
+            Sources.NULL
+        );
+    }
+
     public static UntypedBoolLiteralNode boolLiteral(boolean value) {
         return new UntypedBoolLiteralNode(value, Sources.NULL);
     }
diff --git a/src/test/java/org/shedlang/compiler/typechecker/TypeCheckerBinaryOperationTests.java b/src/test/java/org/shedlang/compiler/typechecker/TypeCheckerBinaryOperationTests.java
new file mode 100644
index 00000000..017c2d97
--- /dev/null
+++ b/src/test/java/org/shedlang/compiler/typechecker/TypeCheckerBinaryOperationTests.java
@@ -0,0 +1,25 @@
+package org.shedlang.compiler.typechecker;
+
+import org.junit.jupiter.api.Test;
+import org.shedlang.compiler.ast.untyped.Untyped;
+import org.shedlang.compiler.types.Types;
+
+import static org.shedlang.compiler.ast.typed.TypedNodeMatchers.isTypedIntAddNode;
+import static org.shedlang.compiler.ast.typed.TypedNodeMatchers.isTypedIntLiteralNode;
+import static org.zwobble.precisely.AssertThat.assertThat;
+import static org.zwobble.precisely.Matchers.equalTo;
+
+public class TypeCheckerBinaryOperationTests {
+    @Test
+    public void whenBothOperandsAreIntsAndOperatorIsAddThenIsTypedAsIntAdd() {
+        var untyped = Untyped.add(Untyped.intLiteral(42), Untyped.intLiteral(47));
+
+        var typed = TypeChecker.typeCheckExpression(untyped, TypeCheckerContext.EMPTY);
+
+        assertThat(typed.value(), isTypedIntAddNode(
+            isTypedIntLiteralNode(42),
+            isTypedIntLiteralNode(47)
+        ));
+        assertThat(typed.value().type(), equalTo(Types.INT));
+    }
+}