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

1 files changed, 25 insertions, 0 deletions

diff --git a/std/examples/tests/cat_test.ts b/std/examples/tests/cat_test.ts
new file mode 100644
index 000000000..93e884f61
--- /dev/null
+++ b/std/examples/tests/cat_test.ts
@@ -0,0 +1,25 @@
+// Copyright 2018-2020 the Deno authors. All rights reserved. MIT license.
+import { assertStrictEq } from "../../testing/asserts.ts";
+
+Deno.test("[examples/cat] print multiple files", async () => {
+  const decoder = new TextDecoder();
+  const process = Deno.run({
+    args: [
+      Deno.execPath(),
+      "--allow-read",
+      "cat.ts",
+      "testdata/cat/hello.txt",
+      "testdata/cat/world.txt"
+    ],
+    cwd: "examples",
+    stdout: "piped"
+  });
+
+  try {
+    const output = await Deno.readAll(process.stdout!);
+    const actual = decoder.decode(output).trim();
+    assertStrictEq(actual, "Hello\nWorld");
+  } finally {
+    process.close();
+  }
+});