fix(rest): PaginatedIterator continues past an empty page with a next link (#3.3)

[mjerris]

The bug

PaginatedIterator._fetch_next (signalwire/signalwire/rest/_pagination.py) terminated pagination with:

if next_url and data:
    ...  # parse cursor, continue
else:
    self._done = True

The and data clause is wrong. A page can legitimately return an empty data array on THIS page while still carrying a links.next cursor (more pages exist) — e.g. a filtered page that matches nothing at the current cursor. On such a page the old condition fell into the else, set _done = True, and silently dropped every subsequent page. Any real items living beyond an empty intermediate page were never yielded.

The fix

Termination is now driven only by the absence of a next link, not by an empty data array:

# before
if next_url and data:
# after
if next_url:

An empty-but-not-last page still parses its links.next cursor and fetches the next page. No public surface change — this is a pure bugfix (SEMVER-DIFF gate confirms no version bump required).

Regression test (proven to fail on old code)

Added TestPaginatedIterator::test_empty_page_with_next_continues in tests/unit/rest/test_pagination_mock.py, driven over the shared mock_signalwire server:

• Page 1 → {data: [], links.next: ".../addresses?cursor=page2"} (empty, but more pages)
• Page 2 → {data: [{id: "addr-late"}], links: {}} (terminal)

It asserts the iterator yields addr-late and issued 2 GETs (the second carrying cursor=page2).

• Against the old if next_url and data: code: FAILS — collected == [], page 2 is never fetched (iterator marked done on the empty page 1).
• After the fix: PASSES.

Verification

PORTING_SDK=/Users/michaeljerris/src/porting-sdk bash scripts/run-ci.sh → CI PASS (all gates green, including TEST, TYPECHECK, LINT, FMT, REST-COVERAGE, SPEC-PARITY, PAGINATION-WIRED, SEMVER-DIFF).

🤖 Generated with Claude Code

https://claude.ai/code/session_01PqshDQajCmDHD3xPo4CXMC