fix(std/examples): add tests for examples (#4094)

1 files changed, 19 insertions, 0 deletions

diff --git a/std/examples/tests/welcome_test.ts b/std/examples/tests/welcome_test.ts
new file mode 100644
index 000000000..76209cfad
--- /dev/null
+++ b/std/examples/tests/welcome_test.ts
@@ -0,0 +1,19 @@
+// Copyright 2018-2020 the Deno authors. All rights reserved. MIT license.
+import { assertStrictEq } from "../../testing/asserts.ts";
+
+Deno.test("[examples/welcome] print a welcome message", async () => {
+  const decoder = new TextDecoder();
+  const process = Deno.run({
+    args: [Deno.execPath(), "welcome.ts"],
+    cwd: "examples",
+    stdout: "piped"
+  });
+  try {
+    const output = await Deno.readAll(process.stdout!);
+    const actual = decoder.decode(output).trim();
+    const expected = "Welcome to Deno 🦕";
+    assertStrictEq(actual, expected);
+  } finally {
+    process.close();
+  }
+});