Add tests for example commands

test/test_example_cmd.py

@@ -0,0 +1,19 @@
+import pytest
+
+from psh import echo, example
+from utils import TestFormatter
+
+
+@pytest.fixture
+def test_formatter():
+    return TestFormatter()
+
+
+def test_example_cmd_should_return_two_things(test_formatter):
+    example.chain(test_formatter).call()
+    assert "examplecommand" == test_formatter.get_data()
+
+
+def test_echo_should_echo(test_formatter):
+    example.chain(echo).chain(test_formatter).call()
+    assert "examplecommand" == test_formatter.get_data()

test/utils.py

@@ -0,0 +1,18 @@
+from psh.commands import BaseCommand
+
+from io import StringIO
+
+class TestFormatter(BaseCommand):
+
+    def __init__(self, *args, **kwargs):
+        super(TestFormatter, self).__init__(*args, **kwargs)
+        self.buffer = StringIO()
+
+    def call(self):
+        input_generator = self.get_input_generator()
+        for line in input_generator:
+            self.buffer.write(line.decode('utf-8'))
+        return None
+
+    def get_data(self):
+        return self.buffer.getvalue()