[akhil9tiet]

Fixes #5405

AnswersSolver::check_dict_items_against_typed_dict skips the missing-required-key check whenever has_expansion is true; when a TypedDict is unpacked its required keys should count as present, skipping only for unknown-key types like plain dict.

In check_dict_items_against_typed_dict, the blanket has_expansion flag is replaced with has_unknown_expansion: when an unpacked value is a TypedDict, its required keys are added to the known keys set, so a missing required key is still reported; the check is skipped only when unpacking a type whose keys are unknown, such as a plain dict. Added test_typed_dict_unpacking_missing_required_key, which unpacks an open TypedDict and a closed TypedDict into Target (both missing y) and includes the positive case of unpacking Target itself.

[meta-codesync]

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[stroxler]

Thanks!

Based on AI review, I think there's one issue we should address before merge:

Anonymous TypedDict fields aren’t counted as present

[typed_dict.rs:185–194](

pyrefly/pyrefly/lib/alt/class/typed_dict.rs

Lines 185 to 194 in 658d0cf

	if let Type::TypedDict(unpacked) = &item_ty {
	let unpacked_fields = self.typed_dict_fields(unpacked);
	for (key, field) in &unpacked_fields {
	if field.required {
	keys.insert(key.clone());
	}
	}
	} else {
	has_unknown_expansion = true;
	}

)

Type::TypedDict(unpacked) matches both declared and anonymous TypedDicts. Pyrefly infers ordinary dictionary literals as anonymous TypedDicts with required: false on every field. The new loop therefore adds no keys, but leaves has_unknown_expansion false.

Source tracing indicates this now reports a missing x:

from typing import TypedDict

class Target(TypedDict):
    x: int

def f() -> Target:
    source = {"x": 1}
    return {**source}  # Newly reports missing required key `x`

Smallest fix: restrict required-field counting to TypedDict::TypedDict, preserving the unknown-expansion fallback for anonymous TypedDicts. Add the example above as a regression test.

The declared-TypedDict behavior otherwise looks correct, and the change is appropriately localized. I’d also add a NotRequired source-field test to protect the distinction between declared optional fields and inferred dictionary entries.

[akhil9tiet]

Fixed — the required-field counting in the unpack arm is now restricted to declared TypedDict::TypedDict; anonymous TypedDicts (e.g. inferred dict literals, all fields required: false) fall through to the unknown-expansion path so no missing-key error fires. Added the dict-literal regression test plus a NotRequired source-field test guarding the declared-optional vs inferred distinction.

[github-actions]

According to mypy_primer, this change doesn't affect type check results on a corpus of open source code. ✅