Add pipeline test

src/pipeline.test.ts

@@ -0,0 +1,42 @@
+import { assertEquals } from './deps.ts';
+
+import pipeline from './pipeline.ts';
+import noopPolicy from './policies/noop-policy.ts';
+import readOnlyPolicy from './policies/read-only-policy.ts';
+import { buildInputMessage } from './test.ts';
+
+Deno.test('passes events through multiple policies', async () => {
+  const msg = buildInputMessage();
+
+  const result = await pipeline(msg, [
+    noopPolicy,
+    readOnlyPolicy,
+  ]);
+
+  assertEquals(result.action, 'reject');
+  assertEquals(result.msg, 'The relay is read-only.');
+});
+
+Deno.test('short-circuits on the first reject', async () => {
+  const msg = buildInputMessage();
+
+  const result = await pipeline(msg, [
+    readOnlyPolicy,
+    noopPolicy,
+  ]);
+
+  assertEquals(result.action, 'reject');
+  assertEquals(result.msg, 'The relay is read-only.');
+});
+
+Deno.test('accepts when all policies accept', async () => {
+  const msg = buildInputMessage();
+
+  const result = await pipeline(msg, [
+    noopPolicy,
+    noopPolicy,
+    noopPolicy,
+  ]);
+
+  assertEquals(result.action, 'accept');
+});