Narrow none_member in JSON schema union handling - #1121
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#1028 left none_member typed as `mi.Type | None` and gated the `to_schema(none_member)` calls on a separate `has_none` flag, which mypy can't use to narrow the argument, so mypy (as run by stubtest) reports an incompatible-type error. Drop the flag and check `none_member is not None` directly, which narrows the type and removes a redundant variable. No behavior change.
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The 0.21.1 to 0.22.0 changelog batch (msgspec#1112) landed on 2026-07-03. Four user-visible changes merged between then and the 0.22.0 release on 2026-08-11 never got an entry: - msgspec#700, overloads on the `Meta` stub, so type checkers reject mixing `gt` with `ge` and `lt` with `le` - msgspec#1028, `null` placed last in the `anyOf` generated for optional unions - msgspec#1114, `__struct_encode_fields__` added to `src/msgspec/__init__.pyi` (its companion msgspec#813 only touched `tests/typing`, so it needs no entry of its own) - msgspec#1118, `json.encode` raising `TypeError` for a `dict` keyed by a plain `str`-valued `enum.Enum` I went over every PR merged in that window. The rest need no entry: msgspec#813 and msgspec#1117 are tests only, msgspec#1121 fixes an unreleased regression from msgspec#1028, msgspec#1145 is an unused variable under free-threaded builds, and msgspec#1146 and msgspec#1148 are CI and tooling. msgspec#1127, msgspec#1135 and msgspec#1080 already have entries. Docs build clean with `--fail-on-warning`. Note for whoever retries the release: the section is still headed `Version 0.22.0 (2026-08-11)`, and that date will need updating, since the tag was deleted after the upload failed. Refs msgspec#1134. Co-authored-by: Siyet <[email protected]>
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Follow-up to #1028.
#1028 introduced
none_member: mi.Type | Nonein the union branch of_json_schema.pyand guarded theself.to_schema(none_member)calls with a separatehas_noneboolean. mypy can't narrownone_memberthrough the flag, so it errors:This is not caught by current CI because the msgspec source is not type-checked there (only
tests/typingis); #1116 (adding stubtest) is what surfaces it. Fixing it here so #1116 can go green.The fix drops the redundant
has_noneflag and checksnone_member is not Noneat the call sites, which gives mypy the narrowing. No runtime behavior change (has_noneandnone_memberwere always set together):tests/unit/test_schema.pystill passes (115), and stubtest with mypy 2.2.0 is clean.