[core] stub url path is empty if query url

[l0lawrence]

If the stub_url is a starts with a query "?restype", stub_url_path is then empty and we do not need to append a "/" to the end of parsed_base_url

i.e. https://github.com/l0lawrence/azure-sdk-for-python/blob/9fe8f5081384380ba5f0cfa4803918f5bfcec6ae/sdk/storage/azure-storage-blob/azure/storage/blob/_generated/azure/storage/blobs/_operations/_operations.py#L58C1-L58C46

[pvaneck]

Change LGTM. Let's update the failing test, and also add an assertion where the stub_url is just a query string

[pvaneck]

I think we also need a changelog entry since this affects behavior of the public format_url method.

Something like:

• Fixed PipelineClient.format_url to avoid adding trailing slashes when the URL template contains only query parameters.

Also, looks like we have some recording mismatches in a few of the azure-data-tables tests.

request https://Sanitized.table.core.windows.net/mytable3f8138ee?restype=service&comp=properties
record  https://Sanitized.table.core.windows.net/mytable3f8138ee/?restype=service&comp=properties

@l0lawrence Did the storage recordings not have slashes before the query strings?

[l0lawrence]

I think we also need a changelog entry since this affects behavior of the public format_url method.

Something like:

* Fixed  `PipelineClient.format_url` to avoid adding trailing slashes when the URL template contains only query parameters.

Also, looks like we have some recording mismatches in a few of the azure-data-tables tests.

request https://Sanitized.table.core.windows.net/mytable3f8138ee?restype=service&comp=properties
record  https://Sanitized.table.core.windows.net/mytable3f8138ee/?restype=service&comp=properties

@l0lawrence Did the storage recordings not have slashes before the query strings?

Yes azure-storage-blob doesn't have a slash:

E           Uri doesn't match:
E               request <https://Sanitized.blob.core.windows.net/utcontainerfd23bbd/?restype=container>
E               record  <https://Sanitized.blob.core.windows.net/utcontainerfd23bbd?restype=container>

[pvaneck]

I think we can probably just go ahead and merge. Regarding pipeline failures:

1. The generate_regression_matrix failures were due to an issue already fixed in main.
2. The azure-data-tables test failures were due to recording mismatches, and we can just fix that with [Tables] Fix tests #45101
3. The azure-communication-identity mindependency failures are unrelated to this change. Will be addressed in Remove unnecessary dev dependencies #45097

[Copilot]

Pull request overview

This PR fixes URL formatting in azure-core so that when a URL template/stub begins with query parameters (i.e., no path segment), URL joining no longer injects an extra trailing / into the base URL.

Changes:

• Updated _urljoin to only append "/" + stub_url_path when stub_url_path is non-empty.
• Extended unit coverage for _urljoin to validate query-only stubs and empty stubs.
• Added a changelog entry under Bugs Fixed describing the URL formatting fix.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
sdk/core/azure-core/azure/core/pipeline/transport/_base.py	Adjusts _urljoin behavior to avoid adding a trailing slash when the stub has no path.
sdk/core/azure-core/tests/test_basic_transport.py	Adds assertions covering query-only and empty-stub URL joining behavior.
sdk/core/azure-core/CHANGELOG.md	Documents the bug fix in the Unreleased section.

[l0lawrence]

/check-enforcer override