chore: warn if consumer/provider name has spaces

Signed-off-by: JP-Ellis <josh@jpellis.me>

src/pact/message_consumer.py

@@ -63,6 +63,12 @@ def __init__(
             PendingDeprecationWarning,
             stacklevel=2,
         )
+        if len(name.split()) > 1:
+            warnings.warn(
+                "Consumer name should not contain spaces.",
+                UserWarning,
+                stacklevel=2
+            )
         self.name = name
         self.service_cls = service_cls
         self.tags = tags

src/pact/provider.py

@@ -21,4 +21,10 @@ def __init__(self, name):
             PendingDeprecationWarning,
             stacklevel=2,
         )
+        if len(name.split()) > 1:
+            warnings.warn(
+                "Provider name should not contain spaces.",
+                UserWarning,
+                stacklevel=2,
+            )
         self.name = name

tests/test_issue.py

@@ -2,35 +2,29 @@
 Tests for user-reported issues.
 """
 
-import json
-from pathlib import Path
+import pytest
 
-from pact import MessageConsumer, Provider, matchers
+from pact import MessageConsumer, Provider
 
 
-def test_github_850() -> None:
+def test_github_850(recwarn: pytest.WarningsRecorder) -> None:
     """
     See https://github.com/pact-foundation/pact-python/issues/850.
+
+    User reported an issue with Pact files not being written when using consumer
+    and provider names with spaces. A warning was added to the code to alert the
+    user that the names should not contain spaces.
     """
-    contract = MessageConsumer("my_contract_consumer").has_pact_with(
-        Provider("my_contract_provider"),
+    MessageConsumer("my_contract Consumer").has_pact_with(
+        Provider("my_contract Provider"),
         pact_dir="pacts",
     )
 
-    event_data = {
-        "invoice_id": "12345",
-        "amount": 100.00,
-        "currency": "USD",
-        "created": matchers.Format().iso_8601_datetime(),
-    }
-
-    contract.given("Create contract").expects_to_receive(
-        "An event of contract"
-    ).with_content(event_data)
-
-    with contract:
-        pass
-
-    with Path("pacts/my_contract_consumer-my_contract_provider.json").open() as f:
-        data = json.load(f)
-    assert data["messages"][0]["contents"]["created"] == "1991-02-20T06:35:26+00:00"
+    # Check for warnings
+    warnings = [str(warning.message) for warning in recwarn]
+    assert any(
+        "Consumer name should not contain spaces." in warning for warning in warnings
+    )
+    assert any(
+        "Provider name should not contain spaces." in warning for warning in warnings
+    )