Rebecca Chen

Take narrowed facets' new `present` bit into account in subscript inference Summary: When a dict key facet is known to be present due to an `in` check, suppress errors on key access about the key possibly being absent. Adds a regression test for a tricky corner case that an earlier draft got wrong: overwriting the value should not affect presence. Note that this updates subscripting to handle the `present` bit correctly but does not yet update `narrow.rs` to *set* the `present` bit, so user-facing behavior is not yet fixed. Reviewed By: yangdanny97 Differential Revision: D107801901 fbshipit-source-id: 2854cab22c0ec167edb48fca8111c0d8e2c8d8ef

Change AnswersSolver::error to take ErrorKind directly [9/16] Summary: Pyrefly's error reporting API has grown unwieldy. ErrorCollector currently has two methods for emitting errors (add and add_with_annotations_and_quick_fixes) whose signatures grow every time we add a new optional decoration like annotations or quick fixes. This stack introduces a builder pattern (design: P2307835290, implementation plan: P2307836987) that replaces these methods with an error_builder() returning a chainable ErrorBuilder, making error construction explicit and extensible. This commit changes AnswersSolver::error from taking ErrorInfo to taking ErrorKind directly. After commits 6-7 migrated all ErrorInfo::new and ErrorInfo::Context call sites away, only ErrorInfo::Kind(k) callers remain — this is a purely mechanical replacement. The method now delegates to error_builder internally. All ~250 callers are updated to pass ErrorKind directly, and unused ErrorInfo imports are removed. Reviewed By: fangyi-zhou Differential Revision: D103990096 fbshipit-source-id: e74b693775121033dde6a58c4a8d76ae09779124

Exclude union names from ordering and type equality Summary: Unions should be compared only by their members; the name is display-only metadata. Reviewed By: yangdanny97 Differential Revision: D112931511 fbshipit-source-id: 1f1419eebdcbd079a7248d93a58388a925d71962

Move residual-related functions that only operate on Type + TypeHeap to the types crate Summary: This stack: reorganizes some of the callable residual code to make it clearer which parts of the logic are tightly coupled to the solver, which will make it easier for me to make solver changes. This diff: moves Solver functions that access nothing from the Solver except `self.heap` into the types crate. They are turned into methods on the appropriate types that accept a `&TypeHeap` argument. No functional change. Reviewed By: yangdanny97 Differential Revision: D106045944 fbshipit-source-id: bb7abe3efa6dca4bacff3bcabd00fb7812359f7a

Migrate direct ErrorCollector::add calls to builder [10/16] Summary: Pyrefly's error reporting API has grown unwieldy. ErrorCollector currently has two methods for emitting errors (add and add_with_annotations_and_quick_fixes) whose signatures grow every time we add a new optional decoration like annotations or quick fixes. This stack introduces a builder pattern (design: P2307835290, implementation plan: P2307836987) that replaces these methods with an error_builder() returning a chainable ErrorBuilder, making error construction explicit and extensible. This commit migrates all ~48 direct errors.add(range, ErrorInfo::Kind(k), vec1![msg]) calls to use the builder. Single-line messages become errors.error_builder(range, kind, msg).emit(). Multi-line Vec1 messages are split into header + with_detail() chains. Dynamic Vec1 built with pushes are converted to conditional builder chains. Files modified across alt/, binding/, module/, and state/. Unused ErrorInfo and vec1 imports are removed. Reviewed By: fangyi-zhou Differential Revision: D103990088 fbshipit-source-id: 5f2a534ec943b5e50e8fb6bbbd18da5696417841

Fix overly aggressive cyclic self-reference check Summary: Improves pyrefly's check for cyclic self-references in recursive aliases to accept more aliases. The only ones it rejects now are: * Uninhabited types, like `type X = tuple[X, X]`. * Types that are inhabited only by nestings of empty containers, like `type Y = list[Y]`. * Union types where the self-reference is pointless, like `type Z = int | Z`. Fixes https://github.com/facebook/pyrefly/issues/3235. Reviewed By: yangdanny97 Differential Revision: D107783755 fbshipit-source-id: c30975f36d8f9a39438f76306e77f17633015a52

Check for when a quantified satisfies another quantified's constraints Summary: is_subset_eq's logic for determining whether a type T satisifies a constrained Quantified failed to take into account the case in which T is also a Quantified. This diff adds handling for that case, in a new `quantified_satisfies_constraints` method. Reviewed By: stroxler Differential Revision: D107588970 fbshipit-source-id: d7bdea3d91b4d41228482698c975f40b466c48a0

Detect Final status changes in incremental export diffing Summary: `Exports::changed_exports` was not comparing `final_names` between old and new definitions, so adding or removing a `Final` annotation on an export would not be detected as a metadata change. This meant downstream modules depending on finality (via `ExportOrigin`) would not be re-checked, leading to stale errors. Add `final_names` to the metadata comparison in `changed_exports`. Reviewed By: grievejia Differential Revision: D104303060 fbshipit-source-id: 1c44c905bd4e8f33b705a47f83ed168fe24b45c2

Unify var traversal in solver.rs Summary: * Adds a new `resolve_vars` function that handles var traversal for both `expand_vars` and `deep_force`, allowing us to clean up some duplication and redundant helpers. * Moves dimension canonicalization into `simplify_mut` so we can get rid of `simplify_forced_type`. * Removes a couple no-longer-relevant TODOs. No functional change. Reviewed By: yangdanny97 Differential Revision: D106076328 fbshipit-source-id: 63d4277da296a6380cca01a06f8308ab19a625b3

Backfill missing release notes Summary: Backfills missing release notes for 0.58.0 - 0.63.0. Once this diff is approved, I'll edit these into the corresponding releases. 0.59.0 already has release notes on GitHub, so all I did for that version was copy the existing notes into the release_notes directory. There was already an md file for 0.60.0, but it hadn't been copied to the GitHub release, and the content looked a little questionable anyway, so I re-generated it. Reviewed By: ndmitchell Differential Revision: D103356172 fbshipit-source-id: a4e073ed3a8a14b0994a05a5fbdc19a27e31b2f9

Simplify `finish_quantified_*` cluster of Solver functions Summary: Previously, the solver had five finish_quantified_* functions: three pub, one pub(crate), and one private. This diff gets us down to two: one pub and one private. It also adds a `finish_quantified` wrapper on AnswersSolver to reduce boilerplate, like we do already do with `is_subset_eq` and friends. This *is* a functional change: we now always create a Subset object and do overload pruning when calling `finish_quantified`. CI does not find any change to user-facing behavior. Reviewed By: yangdanny97 Differential Revision: D106052351 fbshipit-source-id: 8307e2ff6f1941b013d6b1d320073d48acea962e

Create `pyrefly/lib/alt/types/instance.rs` Summary: Moves `InstanceKind` and `Instance` into their own file in preparation for reusing them. No functional change. Reviewed By: grievejia Differential Revision: D105456425 fbshipit-source-id: 8c7b1765afe9ee156684c472e1c84d16da814aa4

Sanitize self-referential vars when pruning overload branches Summary: Fixes https://github.com/facebook/pyrefly/issues/3749. Reviewed By: yangdanny97 Differential Revision: D108200384 fbshipit-source-id: d6a629f4f0a083f6697e1895828db85daa491d58

Rename `expected_types` to `argmap` and wrap it in a struct Summary: No functional change. I'm planning to add more info to this map, so let's first rename it and make it more structured. Context: This stack is a ground-up re-implementation of https://github.com/facebook/pyrefly/pull/1447. It has a narrower focus (just omits irrelevant parameter types, doesn't try to do any handling of other kinds of call errors), reuses the existing signature display code, tracks parameters by name instead of index, and filters all overload signatures rather than just the closest one. Reviewed By: grievejia Differential Revision: D108230388 fbshipit-source-id: 3a7f63d9143cc2767566f414b7994e4eff015d5c

Fix all clippy warnings Summary: Looks like we got upgraded to a new Rust version. Warnings fixed: - **collapsible_match** (16 instances): Collapsed `if` conditions inside match arms into match guards in `ast.rs`, `folding.rs`, `simplify.rs`, `code_lens.rs`, `hover.rs`, `inlay_hints.rs`, `convert.rs`, `inline_variable.rs`, `pytest_fixture.rs`, `lsp.rs`, `extract.rs` - **unnecessary_sort_by** (3): Replaced `sort_by(|a, b| a.x.cmp(&b.x))` with `sort_by_key(|a| a.x)` in `report.rs`, `semantic_tokens.rs` - **while_let_loop** (3): Converted `loop { let Some(...) = ... else { break }; ... }` to `while let Some(...) = ... { ... }` in `server.rs`, `state.rs` - **dead_code** (1): Removed unused method `enclosing_class_and_metadata_keys` in `scope.rs` - **manual_checked_ops** (1): Replaced manual division-by-zero check with `checked_div` in `server.rs` - **useless_conversion** (1): Removed unnecessary `.into_iter()` in `dict_completions.rs` - **iter_kv_map** (1): Replaced `.iter().flat_map(|(h, _)| ...)` with `.keys().flat_map(|h| ...)` in `state.rs` - **Redundant guard** (1): Removed duplicate condition check in `simplify.rs` where the match guard already checked the same condition as the inner `if` Reviewed By: stroxler Differential Revision: D103764683 fbshipit-source-id: 0911b3141a9fe6abb171a82ea05153bcb02ca0f7

Read generic residuals from the call context Summary: Context: this stack migrates generic residuals from being stored on Variable to being stored on CallContext. This has several advantages: * This makes generic residuals look a lot more like overload residuals, which will enable code sharing in a later diff. * Separating residuals and variables makes the solver (a little) more modular. * At least to me, it makes more sense for the conceptual unit to be a *set* of residuals associated with a call, rather than a single residual describing a standalone property of a variable. This diff: switches `generalize_class_targs` and `finish_quantified_with_pruning` to read generic residual information from `GenericResidualCapture` on `CallContext` instead of the `residuals` field on `Variable::Quantified`. Remove the dual-write from the previous diff. One wrinkle is that during Callable subset checking, contravariant parameter comparisons negate the `argument_side`, which disables `record_deferred_residual_target_vars` for parameter-side vars. Those vars only appear in `witness_vars` indirectly — through union-find unification with vars that ARE in `witness_vars`. To handle this, we have to resolves vars through the union-find root before matching against `witness_vars`. Also stores generic residuals in overload branch snapshots, so `materialize_overload_residual_branch_value` can determine whether a snapshotted `Quantified` var should produce a `callable_residual_generic` type. Reviewed By: stroxler Differential Revision: D106163696 fbshipit-source-id: 1570cdb954f63fe6d829b94b5118178538b661f1

Remove unnecessary parameters from `FuncMetadata::def` Summary: `FuncMetadata::def` took (module, cls, func, def_index), but really only needs to take cls and func. The module can be computed from the class, and def_index was None at every call site. Note: callers were previously inconsistent about whether we used the module from the class or the current module, but we really should be using the module from the class. Reviewed By: migeed-z Differential Revision: D103759635 fbshipit-source-id: ce16b175376a592406b7a43fe555680ffd1144d9

Expand recursive type aliases in `infer_with_decomposed_hint` Summary: Contextual typing did not work properly for recursive type aliases, because we treated the recursive reference as a single hint rather than splitting it up. This diff fixes that by replacing the recursive reference with the actual value of the alias in `infer_with_decomposed_hint`. Reviewed By: yangdanny97 Differential Revision: D109517652 fbshipit-source-id: d58eb6af0c3e86b07cac553c5f8347de442bf369

Introduce `expr_with_options` Summary: Context: There are 11 (!!) methods in `expr.rs` whose names begin with `expr` and which do some variation of inferring and/or checking a type for an `Expr`. This stack slims things down to a pair of implementation functions (`expr_infer_impl` and `expr_infer_impl_helper`), one intermediate function that delegates to the implementation functions (`expr_with_options`), and some thin wrappers for common options. The final state will be (**bold** = added, ~~strikethrough~~ = removed): | Function | Status | | --- | --- | | expr_check | kept as a thin wrapper, renamed from expr | | expr_infer | kept as a thin wrapper | | expr_infer_with_hint | kept as a thin wrapper | | expr_infer_with_hint_promote | kept, helper that calls expr_infer_with_hint + promotes | | **expr_with_options** | new intermediate function, delegates to impl | | expr_infer_impl | kept, renamed from expr_infer_type_info_with_hint | | expr_infer_impl_helper | kept, renamed from expr_infer_type_no_trace | | ~~expr_with_separate_check_errors~~ | removed | | ~~expr_with_separate_check_errors_with_call_context~~ | removed | | ~~expr_type_info~~ | removed | | ~~expr_type_info_with_separate_check_errors~~ | removed | | ~~expr_type_info_with_separate_check_errors_with_call_context~~ | removed | --- This diff: adds `ExprOptions` and the `expr_with_options` intermediate function that delegates to `expr_infer_impl` and checks the inferred type against the expected type depending on the options. Re-implements the various existing `expr` functions in terms of `expr_with_options`. A couple are dead now, but we don't remove them yet; we'll do all the deletions in one go later. Reviewed By: yangdanny97 Differential Revision: D107697708 fbshipit-source-id: eedf1561b6ded986852d16f7af523db054097566

Add ability to filter by a parameter set when displaying ParamsList Summary: Adds a `ParamOverlay` enum to control which parameters are included when displaying a ParamsList. The enum has two variants: `All` (include all params) and `Subset(SmallSet<Name>)` (include only this set of params). Anonymous params (name=None) are always included. Params that are not included are replaced with `...`. `/` and `*` markers are always included. This will be used in the next diff to improve signature display in no-matching-overload errors. Context: This stack is a ground-up re-implementation of https://github.com/facebook/pyrefly/pull/1447. It has a narrower focus (just omits irrelevant parameter types, doesn't try to do any handling of other kinds of call errors), reuses the existing signature display code, tracks parameters by name instead of index, and filters all overload signatures rather than just the closest one. Reviewed By: grievejia Differential Revision: D108230385 fbshipit-source-id: 50a4425640cdd31caf8bfc644f07d3cab7fc6545