Make it better

Author: lmazuel

sdk/core/azure-core/azure/core/pipeline/transport/_base.py

@@ -730,7 +730,13 @@ def format_url(self, url_template, **kwargs):
             parsed = urlparse(url)
             if not parsed.scheme or not parsed.netloc:
                 url = url.lstrip("/")
-                base = _format_url_section(self._base_url, **kwargs).rstrip("/")
+                try:
+                    base = self._base_url.format(**kwargs).rstrip("/")
+                except KeyError as key:
+                    raise ValueError(
+                        "The value provided for the url part {} was incorrect, and resulted in an invalid url".format(key.args[0])
+                    )
+
                 url = _urljoin(base, url)
         else:
             url = self._base_url.format(**kwargs)

sdk/core/azure-core/tests/test_pipeline.py

@@ -207,9 +207,9 @@ def test_format_url_no_base_url(self):
     def test_format_incorrect_endpoint(self):
         # https://github.com/Azure/azure-sdk-for-python/pull/12106
         client = PipelineClientBase('{Endpoint}/text/analytics/v3.0')
-        formatted = client.format_url("foo/bar")
-        # We don't care about the value, we care it doesn't fail
-        assert formatted is not None
+        with pytest.raises(ValueError) as exp:
+            client.format_url("foo/bar")
+        assert str(exp.value) == "The value provided for the url part Endpoint was incorrect, and resulted in an invalid url"
 
 class TestClientRequest(unittest.TestCase):
     def test_request_json(self):