1 files changed, 160 insertions, 0 deletions
diff --git a/test/signature_match.spec.ts b/test/signature_match.spec.ts
new file mode 100644
index 0000000..10be880
--- /dev/null
+++ b/test/signature_match.spec.ts
@@ -0,0 +1,160 @@
+import { expect, test } from 'bun:test';
+import { TestPrograms } from './programs';
+import { peggyParse } from '@/parser';
+import {
+  evaluate,
+  type DenotableFunctionSignature,
+  denotableTypesEquivalent,
+  matchSignature,
+} from '@/interpreter';
+import { testingLogger } from './logger';
+
+test('simple denotable types are equivalent', () => {
+  expect(denotableTypesEquivalent('int', 'int')).toBe(true);
+  expect(denotableTypesEquivalent('int', 'real')).toBe(false);
+  expect(denotableTypesEquivalent('int', 'null')).toBe(false);
+  expect(denotableTypesEquivalent('null', 'null')).toBe(true);
+});
+
+test('union data types are equivalent', () => {
+  expect(denotableTypesEquivalent(['int', 'real'], ['int', 'real'])).toBe(true);
+  expect(denotableTypesEquivalent('int', ['int', 'real'])).toBe(false);
+});
+
+test('function data types are equivalent', () => {
+  expect(
+    denotableTypesEquivalent(
+      [
+        {
+          arguments: ['int', 'real'],
+          return: 'int',
+        },
+      ],
+      [
+        {
+          arguments: ['int', 'real'],
+          return: 'int',
+        },
+      ],
+    ),
+  ).toBe(true);
+
+  expect(
+    denotableTypesEquivalent(
+      [
+        {
+          arguments: ['int', 'real'],
+          return: 'real',
+        },
+      ],
+      [
+        {
+          arguments: ['int', 'real'],
+          return: 'int',
+        },
+      ],
+    ),
+  ).toBe(false);
+});
+
+test('matches simple signatures', async () => {
+  const simpleSignature: DenotableFunctionSignature[] = [
+    {
+      arguments: ['int'],
+      return: 'int',
+    },
+  ];
+
+  expect(matchSignature(['int'], simpleSignature)).toEqual(simpleSignature[0]);
+});
+
+test('finds first match', async () => {
+  const simpleSignature: DenotableFunctionSignature[] = [
+    {
+      arguments: ['int', 'int'],
+      return: 'int',
+    },
+    {
+      arguments: [['int', 'real'], 'int'],
+      return: 'real',
+    },
+  ];
+
+  expect(matchSignature(['int', 'int'], simpleSignature)).toEqual(
+    simpleSignature[0],
+  );
+
+  expect(matchSignature(['real', 'int'], simpleSignature)).toEqual(
+    simpleSignature[1],
+  );
+});
+
+test('finds first match with a function signature', async () => {
+  const testSignature: DenotableFunctionSignature = {
+    arguments: ['int', 'real'],
+    return: 'int',
+  };
+
+  const simpleSignature: DenotableFunctionSignature[] = [
+    {
+      arguments: ['int', 'int'],
+      return: 'int',
+    },
+    {
+      arguments: [[testSignature, 'real'], 'int'],
+      return: 'function',
+    },
+  ];
+
+  expect(matchSignature(['int', 'int'], simpleSignature)).toEqual(
+    simpleSignature[0],
+  );
+
+  expect(matchSignature(['real', 'int'], simpleSignature)).toEqual(
+    simpleSignature[1],
+  );
+
+  expect(matchSignature([testSignature, 'int'], simpleSignature)).toEqual(
+    simpleSignature[1],
+  );
+});
+
+test('finds first match with a function with many signatures', async () => {
+  const testSignature: DenotableFunctionSignature[] = [
+    {
+      arguments: ['int', 'real'],
+      return: 'int',
+    },
+    {
+      arguments: ['int', 'int'],
+      return: 'int',
+    },
+  ];
+
+  const simpleSignature: DenotableFunctionSignature[] = [
+    {
+      arguments: ['int', 'int'],
+      return: 'int',
+    },
+    {
+      arguments: [[testSignature, 'real'], 'int'],
+      return: 'function',
+    },
+  ];
+
+  expect(matchSignature(['int', 'int'], simpleSignature)).toEqual(
+    simpleSignature[0],
+  );
+
+  expect(matchSignature(['real', 'int'], simpleSignature)).toEqual(
+    simpleSignature[1],
+  );
+
+  expect(matchSignature([testSignature, 'int'], simpleSignature)).toEqual(
+    simpleSignature[1],
+  );
+
+  expect(
+    matchSignature([[testSignature[0]], 'int'], simpleSignature),
+  ).toBeUndefined();
+});