Bullet lists in docstrings should end with blank lines

[busunkim96]

// Request for the
// [CreateWorkflow][google.cloud.workflows.v1beta.Workflows.CreateWorkflow]
// method.
message CreateWorkflowRequest {
  // Required. Project and location in which the workflow should be created.
  // Format:  projects/{project}/locations/{location}
  string parent = 1 [
    (google.api.field_behavior) = REQUIRED,
    (google.api.resource_reference) = {
      type: "locations.googleapis.com/Location"
    }
  ];

  // Required. Workflow to be created.
  Workflow workflow = 2 [(google.api.field_behavior) = REQUIRED];

  // Required. The ID of the workflow to be created. It has to fulfill the
  // following requirements:
  //
  // * Must contain only letters, numbers, underscores and hyphens.
  // * Must start with a letter.
  // * Must be between 1-64 characters.
  // * Must end with a number or a letter.
  // * Must be unique within the customer project and location.
  string workflow_id = 3 [(google.api.field_behavior) = REQUIRED];
}

Gets turned into

            workflow_id (:class:`str`):
                Required. The ID of the workflow to be created. It has
                to fulfill the following requirements:

                -  Must contain only letters, numbers, underscores and
                   hyphens.
                -  Must start with a letter.
                -  Must be between 1-64 characters.
                -  Must end with a number or a letter.
                -  Must be unique within the customer project and
                   location.
                This corresponds to the ``workflow_id`` field
                on the ``request`` instance; if ``request`` is provided, this
                should not be set.

Which results in a Sphinx warning

WARNING: Bullet list ends without a blank line; unexpected unindent.

[larkee]

I am also encountering this in the Spanner library:

// The request for [UpdateBackup][google.spanner.admin.database.v1.DatabaseAdmin.UpdateBackup].
message UpdateBackupRequest {
  // Required. The backup to update. `backup.name`, and the fields to be updated
  // as specified by `update_mask` are required. Other fields are ignored.
  // Update is only supported for the following fields:
  //  * `backup.expire_time`.
  Backup backup = 1 [(google.api.field_behavior) = REQUIRED];

  // Required. A mask specifying which fields (e.g. `expire_time`) in the
  // Backup resource should be updated. This mask is relative to the Backup
  // resource, not to the request message. The field mask must always be
  // specified; this prevents any future fields from being erased accidentally
  // by clients that do not know about them.
  google.protobuf.FieldMask update_mask = 2 [(google.api.field_behavior) = REQUIRED];
}

becomes

            backup (:class:`~.gsad_backup.Backup`):
                Required. The backup to update. ``backup.name``, and the
                fields to be updated as specified by ``update_mask`` are
                required. Other fields are ignored. Update is only
                supported for the following fields:

                -  ``backup.expire_time``.
                This corresponds to the ``backup`` field
                on the ``request`` instance; if ``request`` is provided, this
                should not be set.

[tswast]

Happened here, too: googleapis/python-bigquery-reservation#47

Source protos do not include "This corresponds to ...", so this is probably caused by the templates in the generator.

https://github.com/googleapis/googleapis/blob/ab0498dc4bd2bcfcb70ab257e8edfa00f86083a6/google/cloud/bigquery/reservation/v1/reservation.proto#L785-L792

[tswast]

Maybe as simple as removing the nl=False from these templates?

gapic-generator-python/gapic/ads-templates/%namespace/%name/%version/%sub/services/%service/client.py.j2

Line 293 in 09692c4

{{ field.meta.doc|rst(width=72, indent=16, nl=False) }}

gapic-generator-python/gapic/templates/%namespace/%name_%version/%sub/services/%service/async_client.py.j2

Line 141 in 09692c4

{{ field.meta.doc|rst(width=72, indent=16, nl=False) }}

gapic-generator-python/gapic/templates/%namespace/%name_%version/%sub/services/%service/client.py.j2

Line 304 in 09692c4

{{ field.meta.doc|rst(width=72, indent=16, nl=False) }}