Export function-like class attributes as function definitions

Summary:
The pyrefly-based Pysa analysis currently does not see synthesized functions, such as the `__init__` and `__hash__` methods generated by `dataclass`. We are also blind to methods declared with `foo: Callable[.., int]` in the class body.

This diff updates both pyrefly and pysa to consider those as functions, introducing a new `LocalFunctionId` kind `ClassField`.

Reviewed By: tianhan0

Differential Revision: D84843696

fbshipit-source-id: efb1e36d290fbd40160dd3a1e94a74bca1edf081

Author: arthaud

source/analysis/pyrePysaEnvironment.ml

@@ -218,6 +218,46 @@ module PysaClassSummary = struct
     |> Ast.Identifier.SerializableMap.data
 end
 
+module AstResult = struct
+  type 'a t =
+    | Some of 'a
+    | ParseError (* callable in a module that failed to parse *)
+    | TestFile (* callable in a module marked with is_test = true *)
+    | Synthesized (* callable in a synthesized class or function *)
+    | Pyre1NotFound (* callable not found - only raised when using pyre1 *)
+
+  let to_option = function
+    | ParseError -> None
+    | TestFile -> None
+    | Synthesized -> None
+    | Pyre1NotFound -> None
+    | Some ast -> Some ast
+
+
+  let value_exn ~message = function
+    | Some value -> value
+    | ParseError -> Format.sprintf "%s (reason: parser error)" message |> failwith
+    | TestFile -> Format.sprintf "%s (reason: within a test file)" message |> failwith
+    | Synthesized -> Format.sprintf "%s (reason: synthesized function)" message |> failwith
+    | Pyre1NotFound -> Format.sprintf "%s (reason: not found)" message |> failwith
+
+
+  let map ~f = function
+    | Some ast -> Some (f ast)
+    | ParseError -> ParseError
+    | TestFile -> TestFile
+    | Synthesized -> Synthesized
+    | Pyre1NotFound -> Pyre1NotFound
+
+
+  let map_node ~f = function
+    | Some { Ast.Node.value = ast; location } -> Some { Ast.Node.value = f ast; location }
+    | ParseError -> ParseError
+    | TestFile -> TestFile
+    | Synthesized -> Synthesized
+    | Pyre1NotFound -> Pyre1NotFound
+end
+
 let absolute_source_path_of_qualifier ~lookup_source read_only_type_environment =
   let source_code_api =
     read_only_type_environment |> TypeEnvironment.ReadOnly.get_untracked_source_code_api
@@ -448,7 +488,9 @@ module ReadOnly = struct
   let get_class_summary api = global_resolution api |> GlobalResolution.get_class_summary
 
   let get_class_decorators_opt api class_name =
-    get_class_summary api class_name >>| Ast.Node.value >>| fun { decorators; _ } -> decorators
+    match get_class_summary api class_name with
+    | Some { Ast.Node.value = { PyreClassSummary.decorators; _ }; _ } -> AstResult.Some decorators
+    | None -> AstResult.Pyre1NotFound
 
 
   let get_class_attributes api ~include_generated_attributes ~only_simple_assignments class_name =

source/analysis/pyrePysaEnvironment.mli

@@ -102,6 +102,23 @@ module PysaClassSummary : sig
   val get_attributes : t -> PyreClassSummary.Attribute.t list
 end
 
+module AstResult : sig
+  type 'a t =
+    | Some of 'a
+    | ParseError (* callable in a module that failed to parse *)
+    | TestFile (* callable in a module marked with is_test = true *)
+    | Synthesized (* callable in a synthesized class or function *)
+    | Pyre1NotFound (* callable not found - only raised when using pyre1 *)
+
+  val to_option : 'a t -> 'a option
+
+  val value_exn : message:string -> 'a t -> 'a
+
+  val map : f:('a -> 'b) -> 'a t -> 'b t
+
+  val map_node : f:('a -> 'b) -> 'a Ast.Node.t t -> 'b Ast.Node.t t
+end
+
 module ReadWrite : sig
   type t
 
@@ -169,7 +186,7 @@ module ReadOnly : sig
 
   val get_class_summary : t -> string -> PysaClassSummary.t option
 
-  val get_class_decorators_opt : t -> string -> Ast.Expression.t list option
+  val get_class_decorators_opt : t -> string -> Ast.Expression.t list AstResult.t
 
   val get_class_attributes
     :  t ->

source/interprocedural/callGraph.ml

@@ -23,6 +23,7 @@ open Expression
 open Pyre
 module TaintAccessPath = Analysis.TaintAccessPath
 module PyrePysaLogic = Analysis.PyrePysaLogic
+module AstResult = PyrePysaApi.AstResult
 
 module JsonHelper = struct
   let add_optional name value to_json bindings =
@@ -192,7 +193,8 @@ module CallableToDecoratorsMap = struct
   let collect_decorators ~callables_to_definitions_map callable =
     callable
     |> Option.some_if (Target.is_normal callable)
-    >>= Target.CallablesSharedMemory.ReadOnly.get_signature callables_to_definitions_map
+    >>| Target.CallablesSharedMemory.ReadOnly.get_signature callables_to_definitions_map
+    >>= AstResult.to_option
     >>= fun { Target.CallableSignature.decorators; location = define_location; _ } ->
     let decorators = decorators |> List.filter ~f:filter_decorator |> List.rev in
     if List.is_empty decorators then
@@ -2068,6 +2070,7 @@ struct
     let resolve_module_path = Option.value ~default:(fun _ -> None) resolve_module_path in
     callable
     |> Target.CallablesSharedMemory.ReadOnly.get_qualifier callables_to_definitions_map
+    |> AstResult.to_option
     >>= resolve_module_path
     >>| (function
           | { RepositoryPath.filename = Some filename; _ } ->
@@ -4300,6 +4303,7 @@ let resolve_callees
                 Target.CallablesSharedMemory.ReadOnly.get_signature
                   callables_to_definitions_map
                   callee.target
+                |> AstResult.to_option
                 >>| (fun { Target.CallableSignature.parameters; is_stub; _ } ->
                       is_stub
                       || not (List.exists parameters ~f:(parameter_has_annotation callable_class)))
@@ -5530,10 +5534,7 @@ module HigherOrderCallGraph = struct
               Context.callables_to_definitions_map
               target
           with
-          | None ->
-              log "Cannot find define for callable `%a`" Target.pp_pretty_with_kind target;
-              None
-          | Some { Target.CallableSignature.is_stub; parameters; _ } ->
+          | AstResult.Some { Target.CallableSignature.is_stub; parameters; _ } ->
               if is_stub then
                 let () = log "Callable `%a` is a stub" Target.pp_pretty_with_kind target in
                 None
@@ -5542,6 +5543,9 @@ module HigherOrderCallGraph = struct
                   (parameters
                   |> TaintAccessPath.normalize_parameters
                   |> List.map ~f:(fun { TaintAccessPath.NormalizedParameter.root; _ } -> root))
+          | _ ->
+              log "Cannot find define for callable `%a`" Target.pp_pretty_with_kind target;
+              None
       in
       let create_parameter_target_excluding_args_kwargs (parameter_target, (_, argument_matches)) =
         match argument_matches, parameter_target with
@@ -5692,7 +5696,7 @@ module HigherOrderCallGraph = struct
       let stub_targets =
         List.filter_map call_targets_from_callee ~f:(fun { CallTarget.target; _ } ->
             let is_stub =
-              Target.CallablesSharedMemory.ReadOnly.is_stub
+              Target.CallablesSharedMemory.ReadOnly.is_stub_like
                 Context.callables_to_definitions_map
                 target
               |> Option.value ~default:false
@@ -6338,6 +6342,7 @@ module HigherOrderCallGraph = struct
                                 (to avoid bloat), use this API to query the definition. *)
                           Target.CallablesSharedMemory.ReadOnly.get_captures
                             Context.callables_to_definitions_map
+                          |> AstResult.to_option
                       | _ ->
                           Format.asprintf
                             "Expect a single `define_target` but got `[%s]`"

source/interprocedural/callGraphFixpoint.ml

@@ -106,7 +106,7 @@ module CallGraphAnalysis = struct
       callable
       |> Target.strip_parameters
       |> Target.CallablesSharedMemory.ReadOnly.get_define callables_to_definitions_map
-      |> Option.value_exn
+      |> PyrePysaApi.AstResult.value_exn
            ~message:(Format.asprintf "Found no definition for `%a`" Target.pp_pretty callable)
     in
     if Ast.Statement.Define.is_stub (Ast.Node.value define) then

source/interprocedural/fetchCallables.ml

@@ -150,14 +150,33 @@ let from_qualifier_with_pyrefly ~pyrefly_api ~qualifier =
       qualifier
   in
   let is_stub_module = PyreflyApi.ReadOnly.is_stub_qualifier pyrefly_api qualifier in
+  let is_test_module = PyreflyApi.ReadOnly.is_test_qualifier pyrefly_api qualifier in
   let add_target result define_name =
     let target = Target.from_define_name ~pyrefly_api define_name in
-    let { PyreflyApi.CallableMetadata.is_stub = is_stub_define; is_toplevel; is_class_toplevel; _ } =
+    let {
+      PyreflyApi.CallableMetadata.is_stub = is_stub_define;
+      is_toplevel;
+      is_class_toplevel;
+      is_def_statement;
+      _;
+    }
+      =
       PyreflyApi.ReadOnly.get_callable_metadata pyrefly_api define_name
     in
     if is_stub_module && (is_toplevel || is_class_toplevel) then
+      (* Ignore top level define for stub modules (i.e, `.pyi`) *)
       result
-    else if is_stub_define then
+    else if
+      is_stub_define
+      || is_test_module
+      || ((not is_def_statement) && (not is_toplevel) && not is_class_toplevel)
+    then
+      (* Considered as stub:
+       * - Stub functions, i.e when the body is an ellipsis `def foo(): ...`
+       * - Functions in a module considered a unit test module
+       * - Synthesized functions that we don't have the code for (for instance,
+       *   generated `__init__` of a dataclass)
+       *)
       { result with stubs = target :: result.stubs }
     else
       (* TODO(T225700656): For now, all modules are considered internal. We could potentially use

source/interprocedural/globalConstants.ml

@@ -10,6 +10,7 @@ open Ast
 open Statement
 open Expression
 module PyrePysaLogic = Analysis.PyrePysaLogic
+module AstResult = PyrePysaApi.AstResult
 
 module Heap = struct
   type t = StringLiteral.t Reference.Map.t [@@deriving show, equal]
@@ -64,6 +65,7 @@ module Heap = struct
     |> PyrePysaApi.ReadOnly.get_qualifier_top_level_define_name pyre_api
     |> Target.create_function
     |> Target.CallablesSharedMemory.ReadOnly.get_define callables_to_definitions_map
+    |> AstResult.to_option
     >>| (fun { Target.CallablesSharedMemory.DefineAndQualifier.define; _ } -> define)
     >>| Ast.Node.value
     >>| (fun { Ast.Statement.Define.body; _ } -> body)

source/interprocedural/pyrePysaApi.ml

@@ -14,6 +14,7 @@ module ScalarTypeProperties = Pyre1Api.ScalarTypeProperties
 module ClassNamesFromType = Pyre1Api.ClassNamesFromType
 module PysaType = Pyre1Api.PysaType
 module PyreClassSummary = Pyre1Api.PyreClassSummary
+module AstResult = Pyre1Api.AstResult
 
 module PysaClassSummary = struct
   type t =

source/interprocedural/pyrePysaApi.mli

@@ -15,6 +15,7 @@ module ScalarTypeProperties = Analysis.PyrePysaEnvironment.ScalarTypeProperties
 module ClassNamesFromType = Analysis.PyrePysaEnvironment.ClassNamesFromType
 module PysaType = Analysis.PyrePysaEnvironment.PysaType
 module PyreClassSummary = Analysis.ClassSummary
+module AstResult = Analysis.PyrePysaEnvironment.AstResult
 
 (* Abstraction for information about a class, provided from Pyre1 or Pyrefly and used by Pysa. See
    `ReadOnly.ClassSummary` for more functions. *)
@@ -122,7 +123,7 @@ module ReadOnly : sig
 
   val get_class_summary : t -> string -> PysaClassSummary.t option
 
-  val get_class_decorators_opt : t -> string -> Ast.Expression.t list option
+  val get_class_decorators_opt : t -> string -> Ast.Expression.t list AstResult.t
 
   val get_class_attributes
     :  t ->