First couple of tests. Added httpretty

tests/test_slack.py

@@ -1,12 +1,39 @@
+import json
 
+import httpretty
+import pytest
+
+from lolafect.slack import send_message_to_slack_channel
+
+
+@httpretty.activate(allow_net_connect=False, verbose=True)
 def test_send_message_to_slack_channel_works_properly():
-    # Build flow
+    mock_webhook_url = "http://the-webhook-url.com"
+    mock_message_to_channel = "Hi there!"
+    httpretty.register_uri(method=httpretty.POST, uri=mock_webhook_url, status=200)
 
-    # Check that server got the thingy
-    pass
+    send_message_to_slack_channel(
+        webhook_url=mock_webhook_url, text_to_send=mock_message_to_channel
+    )
 
-def test_send_message_to_slack_channel_raises_error():
-    assert 1 == 0
+    request_observed_by_server = httpretty.last_request()
+
+    assert (request_observed_by_server.method == "POST") and (
+        json.loads(request_observed_by_server.body.decode("UTF-8"))
+        == {"text": mock_message_to_channel}
+    )
+
+
+@httpretty.activate(allow_net_connect=False, verbose=True)
+def test_send_message_to_slack_channel_response_400_raises_exception():
+    mock_webhook_url = "http://the-webhook-url.com"
+    mock_message_to_channel = "Hi there!"
+    httpretty.register_uri(method=httpretty.POST, uri=mock_webhook_url, status=400)
+
+    with pytest.raises(ValueError):
+        send_message_to_slack_channel(
+            webhook_url=mock_webhook_url, text_to_send=mock_message_to_channel
+        )
 
 
 def test_flow_with_positive_outcome():
@@ -14,4 +41,4 @@ def test_flow_with_positive_outcome():
 
 
 def test_flow_with_negative_outcome():
-    assert 1 == 0
+    assert 1 == 0