Fix linting issues.

Add tests.

charla/chat.py

@@ -18,6 +18,7 @@
 from charla import config
 
 # UI text
+
 t_open = 'OPEN: '
 t_open_toolbar = 'Add to prompt: '
 t_prompt = 'PROMPT: '
@@ -68,10 +69,9 @@ def get_content(source: str) -> str:
     if source.startswith(('http://', 'https://')):
         try:
             resp = httpx.get(source, follow_redirects=True)
-            if 'text/html' == resp.headers['content-type']:
-                content = html2text(resp.text, baseurl=source)
-            else:
-                content = resp.text
+            content = html2text(
+                resp.text, baseurl=source
+            ) if resp.headers['content-type'] == 'text/html' else resp.text
         except httpx.ConnectError as err:
             print(f'Enter an existing URL.\n{err}\n')
     else:

tests/test_chat.py

@@ -9,10 +9,14 @@ def mock_args():
     return p.parse_args([])
 
 
-# def test_available_models():
-#     models = chat.available_models()
-#     assert len(models)
-#     assert 'name' in models[0]
+def test_get_content_error():
+    assert '' == chat.get_content('https://does-not-exist')
+    assert '' == chat.get_content('does-not-exist.file')
+
+
+def test_get_content_file():
+    content = chat.get_content('./tests/test_chat.py')
+    assert len(content)
 
 
 def test_prompt_session():