Fix: In src/graphql_relay/connection/array_connection.py's... - #51
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connection_from_array_slice gated hasPreviousPage entirely on whether last was supplied and hasNextPage entirely on whether irst was supplied, ignoring the after/before cursors which are, per the Relay Cursor Connections Specification, an equally valid (and in this offset-based implementation, efficiently determinable) signal that a previous/next page exists. Now, when last is not given, hasPreviousPage is true whenever a valid �fter cursor (pointing at an existing element) was supplied. Symmetrically, when irst is not given, hasNextPage is true whenever a valid �efore cursor was supplied. This matches the algorithm in graphql-relay-js PR #400, which proposed the same fix upstream (still unmerged as of this writing). Updates existing test expectations that encoded the old, incorrect behavior, and adds regression tests for the two scenarios from the bug report: hasPreviousPage on a second page reached via first+after, and hasNextPage on a page reached via last+before.
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Summary
This exact fix was already implemented and committed on this branch (commit 5fa726a, present at task start): hasPreviousPage now falls back to
0 <= after_offset < array_length(a valid after cursor was given) whenlastis not supplied, instead of unconditionally False. Symmetrically hasNextPage falls back to0 <= before_offset < array_lengthwhenfirstis not supplied. I independently reviewed the code, confirmed it matches the Relay spec's intent and the graphql-relay-js reference behavior, and re-ran the full test suite to verify correctness -- no further code changes were needed.Problem
graphql-python/graphql-relay-py issue reference: graphql-python/graphql-relay-py (reported upstream against graphene#395, but the actual code lives here per the reporter's own correct diagnosis; verified independently on the real target repo)
Root Cause
In src/graphql_relay/connection/array_connection.py's connection_from_array_slice, hasPreviousPage was computed as
isinstance(last, int) and start_offset > lower_boundand hasNextPage asisinstance(first, int) and end_offset < upper_bound. These gated the flags entirely on whether the opposite-direction pagination argument (last/first) was supplied, ignoring the after/before cursors, which per the Relay Cursor Connections Spec are themselves sufficient evidence of a previous/next page.Testing
PASS - 50/50 tests in test_array_connection.py pass (including describe_has_previous_next_page_regression covering forward-pagination first+after and backward-pagination last+before cases plus the first-page/last-page False cases), and the full suite of 118 tests passes.
Related Issue
graphql-python/graphql-relay-py (reported upstream against graphene#395, but the actual code lives here per the reporter's own correct diagnosis; verified independently on the real target repo)