Add additional unit tests (#190)

* Add additional unit tests

* remove unused import

tests/test_img.py

@@ -2,7 +2,7 @@
 
 """Provides test cases for webexmemebot/img.py."""
 
-import pytest
+import pytest  # pragma: no cover
 
 from app import img  # pragma: no cover
 

tests/test_meme.py

@@ -0,0 +1,36 @@
+#!/usr/bin/env python3
+
+"""Provides test cases for webexmemebot/img.py."""
+
+from webex_bot.models.response import Response  # pragma: no cover
+
+from app import meme  # pragma: no cover
+
+
+def test_adaptive_card_create() -> None:
+    """Test to ensure that the adaptive card is created."""
+    command = meme.MakeMemeCommand()
+    result = command.execute(None, None, None)
+    assert isinstance(result, Response)
+
+
+def test_error_true() -> None:
+    """Test to ensure that execute() exits when error=True."""
+    callback = meme.MakeMemeCallback()
+    callback.error = True
+    result = callback.execute(None, None, None)
+    assert result is None
+
+
+def test_error_false() -> None:
+    """Test to ensure that execute() completes when error=False."""
+    callback = meme.MakeMemeCallback()
+    callback.meme = "oprah.png"
+    callback.text_top = "TEST"
+    callback.text_bottom = "TEST"
+    result: Response = callback.execute(None, None, {"target": {"globalId": "TEST"}})
+    assert (
+        isinstance(result, Response) \
+        and result.roomId == "TEST" \
+        and result.files[0] == callback.meme_filename
+    )