Module: Rigor::Inference::ScopeIndexer

Defined in:
lib/rigor/inference/scope_indexer.rb

Overview

Builds a per-node scope index for a Prism program by running ‘Rigor::Inference::StatementEvaluator` over the root and recording the entry scope visible at every node. Expression-interior nodes the evaluator does not specialise (call receivers, arguments, array/hash elements, …) inherit their nearest statement-y ancestor’s recorded scope, so a downstream caller that looks up the scope for any Prism node in the tree always gets the scope that was effectively visible at that point.

The CLI commands ‘rigor type-of` and `rigor type-scan` consume the index so that local-variable bindings established earlier in the program are visible to the typer when probing later nodes. Without the index, both commands would type every node under an empty scope and miss the constant-folding / dispatch precision that Slice 3 phase 2’s StatementEvaluator unlocks.

The returned object is an identity-comparing Hash:

“‘ruby index = Rigor::Inference::ScopeIndexer.index(program, default_scope: Scope.empty) index #=> the Rigor::Scope visible at that node “`

Nodes that are not part of the program subtree (e.g. synthesised virtual nodes that the caller looks up after the fact) yield the ‘default_scope`. The returned Hash is mutable in principle but callers MUST treat it as read-only; the indexer itself never exposes a way to update it past construction. rubocop:disable Metrics/ModuleLength

Constant Summary collapse

TOP_LEVEL_DEF_KEY =

v0.0.3 A — sentinel key under which ‘record_def_node` files DefNodes that live outside any class / module body (top-level helpers, `def`s nested inside DSL blocks like `RSpec.describe … do; def helper; end`). Looked up by `Scope#top_level_def_for` to give implicit-self calls priority over RBS dispatch when the file defines a same-named local method.

"<toplevel>"
VISIBILITY_MODIFIERS = 
%i[public private protected].freeze

Class Method Summary collapse

Class Method Details

.apply_alias_def_nodes(root, accumulator) ⇒ Object

Post-pass over the ‘def_nodes` accumulator: for every `alias` declaration inside a class body, if the original method name maps to a `Prism::DefNode`, register the new name pointing to the same node so inter-procedural return-type inference works for the aliased name.



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# File 'lib/rigor/inference/scope_indexer.rb', line 713

def apply_alias_def_nodes(root, accumulator)
  alias_map = collect_class_alias_map(root, [], {})
  alias_map.each do |class_name, aliases|
    class_defs = accumulator[class_name]
    next unless class_defs

    aliases.each do |new_name, old_name|
      def_node = class_defs[old_name]
      next unless def_node.is_a?(Prism::DefNode)

      (accumulator[class_name] ||= {})[new_name] = def_node
    end
  end
end

.apply_named_visibility(args, qualified_prefix, visibility, accumulator) ⇒ Object 



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# File 'lib/rigor/inference/scope_indexer.rb', line 676

def apply_named_visibility(args, qualified_prefix, visibility, accumulator)
  class_name = qualified_prefix.join("::")
  args.each do |arg|
    name = visibility_target_name(arg)
    next if name.nil?

    accumulator[class_name] ||= {}
    accumulator[class_name][name] = visibility
  end
end

.apply_visibility_call(call_node, qualified_prefix, current_visibility, accumulator) ⇒ Object

Recognises modifier calls on the implicit-self receiver inside a class body. Returns the (possibly updated) current visibility:

  • ‘private` / `public` / `protected` (no args) —switch the running default for subsequent defs.

  • ‘private :foo, :bar` — back-patch the named methods in the accumulator. Returns `current_visibility` unchanged because the running default does NOT change for this form.



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# File 'lib/rigor/inference/scope_indexer.rb', line 662

def apply_visibility_call(call_node, qualified_prefix, current_visibility, accumulator)
  return current_visibility unless call_node.receiver.nil?
  return current_visibility unless VISIBILITY_MODIFIERS.include?(call_node.name)
  return current_visibility if qualified_prefix.empty?

  args = call_node.arguments&.arguments || []
  if args.empty?
    call_node.name
  else
    apply_named_visibility(args, qualified_prefix, call_node.name, accumulator)
    current_visibility
  end
end

.build_class_cvar_index(root, default_scope) ⇒ Object

Slice 7 phase 6 — class-cvar pre-pass. Same shape as the ivar pre-pass but collects ‘Prism::ClassVariableWriteNode` writes inside ANY def body (instance or singleton) of the enclosing class, because Ruby cvars are shared across both facets. The resulting table is seeded into both instance and singleton method bodies through `Scope#class_cvars_for`.



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# File 'lib/rigor/inference/scope_indexer.rb', line 223

def build_class_cvar_index(root, default_scope)
  accumulator = {}
  walk_class_cvars(root, [], default_scope, accumulator)
  accumulator.transform_values(&:freeze).freeze
end

.build_class_ivar_index(root, default_scope) ⇒ Object

Slice 7 phase 2. Builds the class-level ivar accumulator by walking every ‘Prism::ClassNode` / `Prism::ModuleNode` body, descending into each nested `Prism::DefNode`, and typing every `Prism::InstanceVariableWriteNode` rvalue under a scope that carries the appropriate `self_type` for that def (singleton vs instance). The rvalue is typed with NO local bindings — the pre-pass lacks statement-level threading — so `@x = 1` records `Constant` but `@x = some_local + 1` records `Dynamic` (since `some_local` is unbound at pre-pass time). Multiple writes to the same ivar union via `Type::Combinator.union`.



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# File 'lib/rigor/inference/scope_indexer.rb', line 149

def build_class_ivar_index(root, default_scope)
  accumulator = {}
  walk_class_ivars(root, [], default_scope, accumulator)
  accumulator.transform_values(&:freeze).freeze
end

.build_declaration_artifacts(root) ⇒ Object

Walks the program once for ‘Prism::ModuleNode` and `Prism::ClassNode`, recording the `Singleton` type for the outermost `constant_path` node of each declaration. Inner segments of a `class Foo::Bar::Baz` path remain real references (resolved through the ordinary lexical walk), so we annotate ONLY the topmost path node. Nested declarations contribute their fully qualified path: `class A::B; class C; …` produces `A::B` for the outer and `A::B::C` for the inner.



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# File 'lib/rigor/inference/scope_indexer.rb', line 859

def build_declaration_artifacts(root)
  identity_table = {}.compare_by_identity
  discovered = {}
  record_declarations(root, [], identity_table, discovered)
  [identity_table.freeze, discovered.freeze]
end

.build_discovered_def_nodes(root) ⇒ Object

v0.0.2 #5 — instance-side def-node recording. Walks class bodies the same way as ‘build_discovered_methods` but records the actual `Prism::DefNode` for each instance method so `ExpressionTyper` can re-type the body at the call site for inter-procedural return inference. Singleton methods and `define_method` calls are intentionally skipped: the inference path needs a statically introspectable body, and singleton dispatch has its own complications (Class / Module ancestry) the first-iteration rule does not yet model.



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# File 'lib/rigor/inference/scope_indexer.rb', line 504

def build_discovered_def_nodes(root)
  accumulator = {}
  walk_def_nodes(root, [], false, accumulator)
  apply_alias_def_nodes(root, accumulator)
  accumulator.transform_values(&:freeze).freeze
end

.build_discovered_method_visibilities(root) ⇒ Object

v0.1.2 — per-class method-visibility table for the ‘def.method-visibility-mismatch` CheckRule.

Tracks two visibility-changing forms:

  • **Modifier blocks**: a bare ‘private` / `protected` / `public` call inside a class body switches the “current default” visibility for every subsequent `def` until another modifier flips it again.

  • **Named-argument form**: ‘private :foo, :bar` (or the same with `protected` / `public`) marks specific names already-recorded under the class. Symbol-only args are recognised; `private def foo; end` (the wrap-around form) is not yet — it would need tracking the def-call’s return-value visibility, which is a separate slice.

Top-level (no surrounding class) defs do not contribute — Ruby’s top-level visibility nuances (private at top-level marks the method on ‘Object`) are out of scope for v0.1.2.



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# File 'lib/rigor/inference/scope_indexer.rb', line 585

def build_discovered_method_visibilities(root)
  accumulator = {}
  walk_method_visibilities(root, [], false, :public, accumulator)
  accumulator.transform_values(&:freeze).freeze
end

.build_discovered_methods(root) ⇒ Object

Slice 7 phase 12 — in-source method discovery pre-pass. Walks every class/module body and records the methods introduced via ‘Prism::DefNode` (instance + singleton) and via recognised `define_method(:name) { … }` calls. The returned table maps qualified class name to a `Hash[Symbol, :instance | :singleton]`.



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# File 'lib/rigor/inference/scope_indexer.rb', line 357

def build_discovered_methods(root)
  accumulator = {}
  walk_methods(root, [], false, accumulator)
  accumulator.transform_values(&:freeze).freeze
end

.build_in_source_constants(root, default_scope) ⇒ Object

Slice 7 phase 9 — in-source constant value pre-pass. Walks the entire program (top-level AND inside class / module / def bodies) for ‘Prism::ConstantWriteNode` and `Prism::ConstantPathWriteNode`, types each rvalue, and accumulates by qualified name. Constants defined inside a class body are qualified with the surrounding class path; constants written via a path (`Foo::BAR = …`) use the rendered path as-is.



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# File 'lib/rigor/inference/scope_indexer.rb', line 309

def build_in_source_constants(root, default_scope)
  accumulator = {}
  walk_constant_writes(root, [], default_scope, accumulator)
  accumulator.freeze
end

.build_program_global_index(root, default_scope) ⇒ Object

Slice 7 phase 6 — program-global pre-pass. Globals are process-wide so the accumulator is a flat ‘Hash[Symbol, Type::t]` populated from every `Prism::GlobalVariableWriteNode` in the program (top-level AND inside method bodies). The same accumulator is seeded into every method body and the top-level scope.



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# File 'lib/rigor/inference/scope_indexer.rb', line 281

def build_program_global_index(root, default_scope)
  accumulator = {}
  gather_global_writes(root, default_scope, accumulator)
  accumulator.freeze
end

.collect_class_alias_map(node, qualified_prefix, accumulator) ⇒ Object

Builds a map ‘=> {new_name_sym => old_name_sym}` by walking the tree for `AliasMethodNode` nodes inside class bodies.



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# File 'lib/rigor/inference/scope_indexer.rb', line 730

def collect_class_alias_map(node, qualified_prefix, accumulator)
  return accumulator unless node.is_a?(Prism::Node)

  case node
  when Prism::ClassNode, Prism::ModuleNode
    name = qualified_name_for(node.constant_path)
    if name
      collect_class_alias_map(node.body, qualified_prefix + [name], accumulator) if node.body
      return accumulator
    end
  when Prism::SingletonClassNode
    return accumulator
  when Prism::AliasMethodNode
    record_alias_map_entry(node, qualified_prefix, accumulator)
    return accumulator
  end

  node.compact_child_nodes.each { |child| collect_class_alias_map(child, qualified_prefix, accumulator) }
  accumulator
end

.collect_class_decls(node, qualified_prefix, accumulator) ⇒ Object

Class-only variant of ‘record_declarations` — descends into nested module bodies (so `module Foo; class Bar` registers `Foo::Bar`) but never registers the module itself in `accumulator`.



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# File 'lib/rigor/inference/scope_indexer.rb', line 831

def collect_class_decls(node, qualified_prefix, accumulator)
  return unless node.is_a?(Prism::Node)

  case node
  when Prism::ClassNode
    name = qualified_name_for(node.constant_path)
    if name
      full = (qualified_prefix + [name]).join("::")
      accumulator[full] = Type::Combinator.singleton_of(full)
      return collect_class_decls(node.body, qualified_prefix + [name], accumulator) if node.body
    end
  when Prism::ModuleNode
    name = qualified_name_for(node.constant_path)
    return collect_class_decls(node.body, qualified_prefix + [name], accumulator) if name && node.body
  end

  node.compact_child_nodes.each { |child| collect_class_decls(child, qualified_prefix, accumulator) }
end

.collect_def_cvar_writes(def_node, qualified_prefix, default_scope, accumulator) ⇒ Object 



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# File 'lib/rigor/inference/scope_indexer.rb', line 250

def collect_def_cvar_writes(def_node, qualified_prefix, default_scope, accumulator)
  return if def_node.body.nil? || qualified_prefix.empty?

  class_name = qualified_prefix.join("::")
  body_scope = default_scope.with_self_type(Type::Combinator.nominal_of(class_name))
  gather_cvar_writes(def_node.body, body_scope, class_name, accumulator)
end

.collect_def_ivar_writes(def_node, qualified_prefix, default_scope, accumulator) ⇒ Object 



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# File 'lib/rigor/inference/scope_indexer.rb', line 176

def collect_def_ivar_writes(def_node, qualified_prefix, default_scope, accumulator)
  return if def_node.body.nil? || qualified_prefix.empty?

  class_name = qualified_prefix.join("::")
  singleton = def_node.receiver.is_a?(Prism::SelfNode) ||
              def_receiver_targets_lexical_self?(def_node.receiver, qualified_prefix)
  self_type =
    if singleton
      Type::Combinator.singleton_of(class_name)
    else
      Type::Combinator.nominal_of(class_name)
    end
  body_scope = default_scope.with_self_type(self_type)

  gather_ivar_writes(def_node.body, body_scope, class_name, accumulator)
end

.data_define_call?(node) ⇒ Boolean

Recognises ‘Data.define(*Symbol)` and `Data.define(*Symbol) do … end` at constant-write rvalue position. The receiver MUST be the bare `Data` constant (or `::Data`); other receivers (a local variable, a method call return) are rejected because their identity is not statically known.

Returns:

  • (Boolean) 


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# File 'lib/rigor/inference/scope_indexer.rb', line 923

def data_define_call?(node)
  return false unless node.is_a?(Prism::CallNode)
  return false unless node.name == :define
  return false unless meta_constant_receiver?(node.receiver, :Data)

  args = node.arguments&.arguments || []
  args.all?(Prism::SymbolNode)
end

.def_receiver_targets_lexical_self?(receiver, qualified_prefix) ⇒ Boolean

Only ‘Prism::ConstantReadNode` is observed in real Ruby —Prism mis-parses `def C::P.method` as `def C.P` (Ruby itself rejects the form as a SyntaxError). The ConstantPathNode branch stays defensive in case Prism’s grammar widens.

Returns:

  • (Boolean) 


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# File 'lib/rigor/inference/scope_indexer.rb', line 477

def def_receiver_targets_lexical_self?(receiver, qualified_prefix)
  return false if qualified_prefix.empty?

  case receiver
  when Prism::ConstantReadNode
    receiver.name.to_s == qualified_prefix.last
  when Prism::ConstantPathNode
    rendered = render_constant_path(receiver)
    return false unless rendered

    path = rendered.split("::")
    qualified_prefix.last(path.length) == path
  else
    false
  end
end

.def_singleton?(def_node, qualified_prefix, in_singleton_class) ⇒ Boolean

‘def Foo.bar` inside `module Foo` (or `def Meta.init` inside `module Meta`) is semantically equivalent to `def self.bar`: at the def-site, the runtime value of the constant `Foo` is the module itself (== `self`). Recognise the form so the method registers as singleton on the enclosing class.

The cross-class form ‘def Bar.baz` inside `module Foo` —where the receiver names a constant other than the enclosing class — is not supported at this slice; falls through to `:instance` (current behaviour) rather than silently re-routing the registration.

Returns:

  • (Boolean) 


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# File 'lib/rigor/inference/scope_indexer.rb', line 467

def def_singleton?(def_node, qualified_prefix, in_singleton_class)
  return true if def_node.receiver.is_a?(Prism::SelfNode) || in_singleton_class

  def_receiver_targets_lexical_self?(def_node.receiver, qualified_prefix)
end

.discovered_classes_for_paths(paths, buffer: nil) ⇒ Hash{String => Rigor::Type::Singleton}

Walks every file in ‘paths` (each path is parsed once with `Prism.parse_file`) and returns the unioned project-wide `discovered_classes` Hash: `=> Singleton`. Used by `Analysis::Runner` to seed each file’s ‘default_scope.discovered_classes` so that lexical constant lookup in one file resolves a `class Foo` declared in a sibling file. Per-file collisions are last-write-wins (matches the existing in-file merge semantics). Parse failures fail-soft to an empty contribution. The `buffer` argument, when present, redirects reads for the bound logical path to the buffer’s physical path so editor-mode pre-passes see the in-flight bytes.

**Modules are intentionally excluded** from the project-wide seed: a ‘module M; module_function; def x; end; end` body, when surfaced as `singleton(M)` to the dispatcher, falls through to `Kernel#x` (or any Module ancestor method) when the project’s per-file ‘discovered_methods` doesn’t know ‘M.x` — leading to surprising types like `Kernel.select → Array`. Until cross-file `discovered_methods` follows the same project-wide seed, registering modules here would introduce regressions in modules-with-module_function idioms that previously resolved to `Dynamic`. Class declarations are safe because per-file `discovered_methods` already tracks `def self.x` / `def x` instance and singleton methods consistently.

Parameters:

Returns:



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# File 'lib/rigor/inference/scope_indexer.rb', line 812

def discovered_classes_for_paths(paths, buffer: nil)
  accumulator = {}
  paths.each do |path|
    physical = buffer ? buffer.resolve(path) : path
    source = File.read(physical)
    root = Prism.parse(source, filepath: path).value
    collect_class_decls(root, [], accumulator)
  rescue StandardError
    # Skip files that fail to parse or read; the per-file
    # analyzer surfaces the parse error separately.
    next
  end
  accumulator.freeze
end

.gather_cvar_writes(node, scope, class_name, accumulator) ⇒ Object 



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# File 'lib/rigor/inference/scope_indexer.rb', line 258

def gather_cvar_writes(node, scope, class_name, accumulator)
  return unless node.is_a?(Prism::Node)

  record_cvar_write(node, scope, class_name, accumulator) if node.is_a?(Prism::ClassVariableWriteNode)
  return if IVAR_BARRIER_NODES.any? { |klass| node.is_a?(klass) }

  node.compact_child_nodes.each { |c| gather_cvar_writes(c, scope, class_name, accumulator) }
end

.gather_global_writes(node, scope, accumulator) ⇒ Object 



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# File 'lib/rigor/inference/scope_indexer.rb', line 287

def gather_global_writes(node, scope, accumulator)
  return unless node.is_a?(Prism::Node)

  record_global_write(node, scope, accumulator) if node.is_a?(Prism::GlobalVariableWriteNode)
  node.compact_child_nodes.each { |c| gather_global_writes(c, scope, accumulator) }
end

.gather_ivar_writes(node, scope, class_name, accumulator) ⇒ Object 



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# File 'lib/rigor/inference/scope_indexer.rb', line 196

def gather_ivar_writes(node, scope, class_name, accumulator)
  return unless node.is_a?(Prism::Node)

  record_ivar_write(node, scope, class_name, accumulator) if node.is_a?(Prism::InstanceVariableWriteNode)

  # Don't recurse into nested defs, classes, or modules; their
  # ivars belong to their own enclosing class.
  return if IVAR_BARRIER_NODES.any? { |klass| node.is_a?(klass) }

  node.compact_child_nodes.each { |c| gather_ivar_writes(c, scope, class_name, accumulator) }
end

.index(root, default_scope:) ⇒ Hash{Prism::Node => Rigor::Scope}

Build the scope index for a Prism program subtree.

Parameters:

  • root (Prism::Node) —

    usually a ‘Prism::ProgramNode`, but any subtree the caller wants the indexer to walk works.

  • default_scope (Rigor::Scope) —

    the scope used for the root, and the fallback returned for any Prism node not contained in ‘root`’s subtree.

Returns:

  • (Hash{Prism::Node => Rigor::Scope}) —

    identity-comparing table whose default value is ‘default_scope`.



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# File 'lib/rigor/inference/scope_indexer.rb', line 53

def index(root, default_scope:) # rubocop:disable Metrics/AbcSize
  # Slice A-declarations. Build the declaration overrides
  # first so every scope handed to the StatementEvaluator
  # already carries the table; structural sharing through
  # `Scope#with_local` / `#with_fact` / `#with_self_type`
  # propagates it across every derived scope.
  declared_types, discovered_classes = build_declaration_artifacts(root)
  # Merge the indexer's findings on top of whatever the
  # base scope already carries so callers that seed
  # cross-file class knowledge (e.g. the ADR-14
  # `SigGen::ObservationCollector` pre-walking project
  # `lib/` before scanning `spec/`) keep their seeds
  # alongside the per-file declarations the indexer
  # itself discovers. Indexer-found entries win on
  # collision — same-file declarations are the most
  # specific authority.
  merged_classes = default_scope.discovered_classes.merge(discovered_classes)
  seeded_scope = default_scope
                 .with_declared_types(declared_types)
                 .with_discovered_classes(merged_classes)

  # Slice 7 phase 2. Pre-pass over every class/module body
  # to collect the per-class ivar accumulator. Seeded after
  # declared_types so the rvalue typer in the pre-pass can
  # see declaration overrides.
  class_ivars = build_class_ivar_index(root, seeded_scope)
  seeded_scope = seeded_scope.with_class_ivars(class_ivars)

  # Slice 7 phase 6. Same pre-pass shape for cvars (per
  # class) and globals (program-wide). Globals are also
  # materialised into the top-level scope's `globals` map
  # so reads at the top level (and in CLI probes that do
  # not enter a method body) observe the precise type
  # without consulting the accumulator on every lookup.
  class_cvars = build_class_cvar_index(root, seeded_scope)
  seeded_scope = seeded_scope.with_class_cvars(class_cvars)
  program_globals = build_program_global_index(root, seeded_scope)
  seeded_scope = seeded_scope.with_program_globals(program_globals)
  program_globals.each { |name, type| seeded_scope = seeded_scope.with_global(name, type) }

  # Slice 7 phase 9. In-source constant value tracking.
  # Walks every ConstantWriteNode/ConstantPathWriteNode in
  # the program and types its rvalue under a scope that
  # carries the surrounding qualified prefix as
  # `self_type`, so the rvalue typer sees in-class
  # references resolve correctly. Multiple writes to the
  # same qualified name union via `Type::Combinator.union`.
  in_source_constants = build_in_source_constants(root, seeded_scope)
  seeded_scope = seeded_scope.with_in_source_constants(in_source_constants)

  # Slice 7 phase 12. In-source method discovery. Walks
  # every class/module body for `Prism::DefNode` and
  # recognised `define_method` calls and records the
  # introduced method names. `rigor check` consults the
  # table to suppress false positives for methods the
  # user has defined but no RBS sig describes.
  discovered_methods = build_discovered_methods(root)
  seeded_scope = seeded_scope.with_discovered_methods(discovered_methods)

  # v0.0.2 #5 — also record the def node itself for
  # instance methods so the engine can re-type the body
  # when a call site dispatches against a user-defined
  # method without an RBS sig.
  discovered_def_nodes = build_discovered_def_nodes(root)
  seeded_scope = seeded_scope.with_discovered_def_nodes(discovered_def_nodes)

  # v0.1.2 — per-class table of method visibilities
  # (`:public` / `:private` / `:protected`). The
  # `def.method-visibility-mismatch` CheckRule consults
  # the table to flag explicit-non-self calls to a
  # private user method.
  discovered_method_visibilities = build_discovered_method_visibilities(root)
  seeded_scope = seeded_scope.with_discovered_method_visibilities(discovered_method_visibilities)

  table = {}.compare_by_identity
  table.default = seeded_scope

  on_enter = ->(node, scope) { table[node] = scope unless table.key?(node) }
  StatementEvaluator.new(scope: seeded_scope, on_enter: on_enter).evaluate(root)

  propagate(root, table, seeded_scope)
  table
end

.literal_method_name(node) ⇒ Object 



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# File 'lib/rigor/inference/scope_indexer.rb', line 774

def literal_method_name(node)
  return nil unless node.is_a?(Prism::SymbolNode) || node.is_a?(Prism::StringNode)

  node.unescaped&.to_sym
end

.meta_call_with_name?(node, receiver_name, method_name) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/rigor/inference/scope_indexer.rb', line 949

def meta_call_with_name?(node, receiver_name, method_name)
  return false unless node.is_a?(Prism::CallNode)
  return false unless node.name == method_name

  meta_constant_receiver?(node.receiver, receiver_name)
end

.meta_constant_receiver?(node, expected_name) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/rigor/inference/scope_indexer.rb', line 960

def meta_constant_receiver?(node, expected_name)
  case node
  when Prism::ConstantReadNode
    node.name == expected_name
  when Prism::ConstantPathNode
    node.parent.nil? && node.name == expected_name
  end
end

.meta_new_block_body(node) ⇒ Object

v0.1.2 — when a ‘Const = Data.define(*sym) do … end` / `Const = Struct.new(*sym) do … end` constant write carries a block, the block body holds method overrides whose canonical class is `Const`. Returns the block body node (a `Prism::StatementsNode`) when the rvalue matches; nil otherwise. Used by `walk_methods` / `walk_def_nodes` to push `Const` onto the qualified prefix before recursing.



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# File 'lib/rigor/inference/scope_indexer.rb', line 437

def meta_new_block_body(node)
  return nil unless node.is_a?(Prism::ConstantWriteNode)

  rvalue = node.value
  return nil unless data_define_call?(rvalue) || struct_new_call?(rvalue)

  rvalue.block&.body
end

.propagate(node, table, parent_scope) ⇒ Object

Walks ‘node`’s subtree DFS and fills in scope entries for every Prism node the StatementEvaluator did not visit (i.e. expression- interior nodes like the receiver/args of a CallNode). Those nodes inherit their nearest recorded ancestor’s scope.

‘IfNode` / `UnlessNode` are special-cased: the truthy and falsey branches each get their predicate’s narrowed scope before recursing. This handles expression-position conditionals (e.g. ‘cache = if cond; t; else; e; end` and conditionals nested as call arguments) which are typed by ExpressionTyper without going through `eval_if`’s narrowing path.



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# File 'lib/rigor/inference/scope_indexer.rb', line 999

def propagate(node, table, parent_scope)
  return unless node.is_a?(Prism::Node)

  current_scope =
    if table.key?(node)
      table[node]
    else
      table[node] = parent_scope
      parent_scope
    end

  case node
  when Prism::IfNode
    propagate_if_branches(node, table, current_scope)
  when Prism::UnlessNode
    propagate_unless_branches(node, table, current_scope)
  else
    node.compact_child_nodes.each { |child| propagate(child, table, current_scope) }
  end
end

.propagate_if_branches(node, table, current_scope) ⇒ Object 



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# File 'lib/rigor/inference/scope_indexer.rb', line 1020

def propagate_if_branches(node, table, current_scope)
  truthy_scope, falsey_scope = Narrowing.predicate_scopes(node.predicate, current_scope)
  propagate(node.predicate, table, current_scope) if node.predicate
  propagate(node.statements, table, truthy_scope) if node.statements
  propagate(node.subsequent, table, falsey_scope) if node.subsequent
end

.propagate_unless_branches(node, table, current_scope) ⇒ Object 



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# File 'lib/rigor/inference/scope_indexer.rb', line 1027

def propagate_unless_branches(node, table, current_scope)
  truthy_scope, falsey_scope = Narrowing.predicate_scopes(node.predicate, current_scope)
  propagate(node.predicate, table, current_scope) if node.predicate
  propagate(node.statements, table, falsey_scope) if node.statements
  propagate(node.else_clause, table, truthy_scope) if node.else_clause
end

.qualified_name_for(constant_path_node) ⇒ Object 



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# File 'lib/rigor/inference/scope_indexer.rb', line 969

def qualified_name_for(constant_path_node)
  case constant_path_node
  when Prism::ConstantReadNode
    constant_path_node.name.to_s
  when Prism::ConstantPathNode
    render_constant_path(constant_path_node)
  end
end

.record_alias_map_entry(alias_node, qualified_prefix, accumulator) ⇒ Object 



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# File 'lib/rigor/inference/scope_indexer.rb', line 751

def record_alias_map_entry(alias_node, qualified_prefix, accumulator)
  return if qualified_prefix.empty?
  return unless alias_node.new_name.is_a?(Prism::SymbolNode) && alias_node.old_name.is_a?(Prism::SymbolNode)

  class_name = qualified_prefix.join("::")
  new_name = alias_node.new_name.unescaped.to_sym
  old_name = alias_node.old_name.unescaped.to_sym
  (accumulator[class_name] ||= {})[new_name] = old_name
end

.record_alias_method(alias_node, qualified_prefix, in_singleton_class, accumulator) ⇒ Object

Registers the alias name in the ‘discovered_methods` table so `undefined-method` diagnostics are not emitted for calls to the aliased name. The kind mirrors the surrounding class context (instance inside a regular class body, singleton inside `class << self`).



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# File 'lib/rigor/inference/scope_indexer.rb', line 698

def record_alias_method(alias_node, qualified_prefix, in_singleton_class, accumulator)
  return if qualified_prefix.empty?
  return unless alias_node.new_name.is_a?(Prism::SymbolNode)

  class_name = qualified_prefix.join("::")
  new_name = alias_node.new_name.unescaped.to_sym
  kind = in_singleton_class ? :singleton : :instance
  (accumulator[class_name] ||= {})[new_name] = kind
end

.record_class_or_module?(node, qualified_prefix, identity_table, discovered) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/rigor/inference/scope_indexer.rb', line 881

def record_class_or_module?(node, qualified_prefix, identity_table, discovered)
  name = qualified_name_for(node.constant_path)
  return false unless name

  full = (qualified_prefix + [name]).join("::")
  singleton = Type::Combinator.singleton_of(full)
  identity_table[node.constant_path] = singleton
  discovered[full] = singleton
  child_prefix = qualified_prefix + [name]
  record_declarations(node.body, child_prefix, identity_table, discovered) if node.body
  true
end

.record_constant_write(node, qualified_prefix, default_scope, accumulator, base_name) ⇒ Object 



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# File 'lib/rigor/inference/scope_indexer.rb', line 340

def record_constant_write(node, qualified_prefix, default_scope, accumulator, base_name)
  full = qualified_prefix.empty? ? base_name : "#{qualified_prefix.join('::')}::#{base_name}"
  body_scope = default_scope
  unless qualified_prefix.empty?
    body_scope = body_scope.with_self_type(Type::Combinator.singleton_of(qualified_prefix.join("::")))
  end
  rvalue_type = body_scope.type_of(node.value)
  existing = accumulator[full]
  accumulator[full] = existing ? Type::Combinator.union(existing, rvalue_type) : rvalue_type
end

.record_cvar_write(node, scope, class_name, accumulator) ⇒ Object 



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# File 'lib/rigor/inference/scope_indexer.rb', line 267

def record_cvar_write(node, scope, class_name, accumulator)
  rvalue_type = scope.type_of(node.value)
  accumulator[class_name] ||= {}
  existing = accumulator[class_name][node.name]
  accumulator[class_name][node.name] =
    existing ? Type::Combinator.union(existing, rvalue_type) : rvalue_type
end

.record_declarations(node, qualified_prefix, identity_table, discovered) ⇒ Object 



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# File 'lib/rigor/inference/scope_indexer.rb', line 866

def record_declarations(node, qualified_prefix, identity_table, discovered)
  return unless node.is_a?(Prism::Node)

  case node
  when Prism::ModuleNode, Prism::ClassNode
    return if record_class_or_module?(node, qualified_prefix, identity_table, discovered)
  when Prism::ConstantWriteNode
    return if record_meta_new_constant?(node, qualified_prefix, identity_table, discovered)
  end

  node.compact_child_nodes.each do |child|
    record_declarations(child, qualified_prefix, identity_table, discovered)
  end
end

.record_def_method(def_node, qualified_prefix, in_singleton_class, accumulator) ⇒ Object 



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# File 'lib/rigor/inference/scope_indexer.rb', line 446

def record_def_method(def_node, qualified_prefix, in_singleton_class, accumulator)
  return if qualified_prefix.empty?

  class_name = qualified_prefix.join("::")
  singleton = def_singleton?(def_node, qualified_prefix, in_singleton_class)
  kind = singleton ? :singleton : :instance
  accumulator[class_name] ||= {}
  accumulator[class_name][def_node.name] = kind
end

.record_def_node(def_node, qualified_prefix, in_singleton_class, accumulator) ⇒ Object 



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# File 'lib/rigor/inference/scope_indexer.rb', line 554

def record_def_node(def_node, qualified_prefix, in_singleton_class, accumulator)
  return if def_singleton?(def_node, qualified_prefix, in_singleton_class)

  class_name = qualified_prefix.empty? ? TOP_LEVEL_DEF_KEY : qualified_prefix.join("::")
  accumulator[class_name] ||= {}
  accumulator[class_name][def_node.name] = def_node
end

.record_def_visibility(def_node, qualified_prefix, in_singleton_class, current_visibility, accumulator) ⇒ Object

rubocop:enable Metrics/CyclomaticComplexity, Metrics/MethodLength, Metrics/PerceivedComplexity, Metrics/AbcSize



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# File 'lib/rigor/inference/scope_indexer.rb', line 643

def record_def_visibility(def_node, qualified_prefix, in_singleton_class, current_visibility, accumulator)
  return if def_node.receiver.is_a?(Prism::SelfNode) || in_singleton_class
  return if qualified_prefix.empty?

  class_name = qualified_prefix.join("::")
  accumulator[class_name] ||= {}
  accumulator[class_name][def_node.name] = current_visibility
end

.record_define_method(call_node, qualified_prefix, in_singleton_class, accumulator) ⇒ Object 



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# File 'lib/rigor/inference/scope_indexer.rb', line 761

def record_define_method(call_node, qualified_prefix, in_singleton_class, accumulator)
  return if qualified_prefix.empty?
  return if call_node.arguments.nil? || call_node.arguments.arguments.empty?

  first_arg = call_node.arguments.arguments.first
  method_name = literal_method_name(first_arg)
  return if method_name.nil?

  class_name = qualified_prefix.join("::")
  accumulator[class_name] ||= {}
  accumulator[class_name][method_name] = in_singleton_class ? :singleton : :instance
end

.record_global_write(node, scope, accumulator) ⇒ Object 



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# File 'lib/rigor/inference/scope_indexer.rb', line 294

def record_global_write(node, scope, accumulator)
  rvalue_type = scope.type_of(node.value)
  existing = accumulator[node.name]
  accumulator[node.name] =
    existing ? Type::Combinator.union(existing, rvalue_type) : rvalue_type
end

.record_ivar_write(node, scope, class_name, accumulator) ⇒ Object 



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# File 'lib/rigor/inference/scope_indexer.rb', line 208

def record_ivar_write(node, scope, class_name, accumulator)
  rvalue_type = scope.type_of(node.value)
  accumulator[class_name] ||= {}
  existing = accumulator[class_name][node.name]
  accumulator[class_name][node.name] =
    existing ? Type::Combinator.union(existing, rvalue_type) : rvalue_type
end

.record_meta_new_constant?(node, qualified_prefix, identity_table, discovered) ⇒ Boolean

Recognises class-creating meta calls at constant-write rvalue position and registers ‘Const` (qualified by the surrounding class/module path) as a discovered class. `Const.new(…)` then resolves to a fresh `Nominal` via `meta_new`, instead of the un-narrowed `Dynamic` returned by the default `Class#new` envelope.

Two recognised meta forms:

  • ‘Const = Data.define(*Symbol) [do … end]`

  • ‘Const = Struct.new(*Symbol [, keyword_init: …]) [do … end]`

The block body, if present, is recursed into so any nested class/module declarations in the override block (rare but legal) still feed the discovered table.

Returns:

  • (Boolean) 


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# File 'lib/rigor/inference/scope_indexer.rb', line 909

def record_meta_new_constant?(node, qualified_prefix, identity_table, discovered)
  return false unless data_define_call?(node.value) || struct_new_call?(node.value)

  full = (qualified_prefix + [node.name.to_s]).join("::")
  discovered[full] = Type::Combinator.singleton_of(full)
  record_declarations(node.value, qualified_prefix, identity_table, discovered)
  true
end

.render_constant_path(node) ⇒ Object 



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# File 'lib/rigor/inference/scope_indexer.rb', line 978

def render_constant_path(node)
  prefix =
    case node.parent
    when Prism::ConstantReadNode then "#{node.parent.name}::"
    when Prism::ConstantPathNode then "#{render_constant_path(node.parent)}::"
    else ""
    end
  "#{prefix}#{node.name}"
end

.singleton_class_prefix(node, qualified_prefix) ⇒ Object

Resolves a ‘class << X` body’s qualified prefix.

- `class << self` keeps `qualified_prefix` (the enclosing class).
- `class << Foo` inside `class Foo` collapses to the same prefix
  (semantically `class << self`).
- `class << Foo` not nested in `class Foo` returns `[Foo]`
  so methods defined inside register on Foo's singleton.
- Any other expression (variable, method call) returns nil
  so the walker falls through and skips the body.



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# File 'lib/rigor/inference/scope_indexer.rb', line 412

def singleton_class_prefix(node, qualified_prefix)
  case node.expression
  when Prism::SelfNode
    qualified_prefix
  when Prism::ConstantReadNode, Prism::ConstantPathNode
    rendered = qualified_name_for(node.expression)
    return nil unless rendered

    if !qualified_prefix.empty? && qualified_prefix.last == rendered
      qualified_prefix
    else
      rendered.split("::")
    end
  end
end

.struct_new_call?(node) ⇒ Boolean

Recognises ‘Struct.new(*Symbol)` and `Struct.new(*Symbol, keyword_init: <expr>)` at constant-write rvalue position. A trailing `KeywordHashNode` (the `keyword_init: …` form) is accepted but does not contribute to member discovery; every other argument MUST be a `Prism::SymbolNode`. At least one Symbol member is required —`Struct.new()` is a degenerate form callers don’t typically use.

Returns:

  • (Boolean) 


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# File 'lib/rigor/inference/scope_indexer.rb', line 939

def struct_new_call?(node)
  return false unless meta_call_with_name?(node, :Struct, :new)

  args = node.arguments&.arguments || []
  positional = struct_new_positionals(args)
  return false if positional.nil? || positional.empty?

  positional.all?(Prism::SymbolNode)
end

.struct_new_positionals(args) ⇒ Object 



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# File 'lib/rigor/inference/scope_indexer.rb', line 956

def struct_new_positionals(args)
  args.last.is_a?(Prism::KeywordHashNode) ? args[0..-2] : args
end

.visibility_target_name(arg) ⇒ Object 



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# File 'lib/rigor/inference/scope_indexer.rb', line 687

def visibility_target_name(arg)
  return arg.unescaped.to_sym if arg.is_a?(Prism::SymbolNode) || arg.is_a?(Prism::StringNode)

  nil
end

.walk_class_cvars(node, qualified_prefix, default_scope, accumulator) ⇒ Object 



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# File 'lib/rigor/inference/scope_indexer.rb', line 229

def walk_class_cvars(node, qualified_prefix, default_scope, accumulator)
  return unless node.is_a?(Prism::Node)

  case node
  when Prism::ClassNode, Prism::ModuleNode
    name = qualified_name_for(node.constant_path)
    if name
      child_prefix = qualified_prefix + [name]
      walk_class_cvars(node.body, child_prefix, default_scope, accumulator) if node.body
      return
    end
  when Prism::DefNode
    collect_def_cvar_writes(node, qualified_prefix, default_scope, accumulator)
    return
  end

  node.compact_child_nodes.each do |child|
    walk_class_cvars(child, qualified_prefix, default_scope, accumulator)
  end
end

.walk_class_ivars(node, qualified_prefix, default_scope, accumulator) ⇒ Object 



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# File 'lib/rigor/inference/scope_indexer.rb', line 155

def walk_class_ivars(node, qualified_prefix, default_scope, accumulator)
  return unless node.is_a?(Prism::Node)

  case node
  when Prism::ClassNode, Prism::ModuleNode
    name = qualified_name_for(node.constant_path)
    if name
      child_prefix = qualified_prefix + [name]
      walk_class_ivars(node.body, child_prefix, default_scope, accumulator) if node.body
      return
    end
  when Prism::DefNode
    collect_def_ivar_writes(node, qualified_prefix, default_scope, accumulator)
    return
  end

  node.compact_child_nodes.each do |child|
    walk_class_ivars(child, qualified_prefix, default_scope, accumulator)
  end
end

.walk_constant_writes(node, qualified_prefix, default_scope, accumulator) ⇒ Object 



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# File 'lib/rigor/inference/scope_indexer.rb', line 315

def walk_constant_writes(node, qualified_prefix, default_scope, accumulator)
  return unless node.is_a?(Prism::Node)

  case node
  when Prism::ClassNode, Prism::ModuleNode
    name = qualified_name_for(node.constant_path)
    if name
      child_prefix = qualified_prefix + [name]
      walk_constant_writes(node.body, child_prefix, default_scope, accumulator) if node.body
      return
    end
  when Prism::ConstantWriteNode
    record_constant_write(node, qualified_prefix, default_scope, accumulator, node.name.to_s)
    return
  when Prism::ConstantPathWriteNode
    full = qualified_name_for(node.target)
    record_constant_write(node, [], default_scope, accumulator, full) if full
    return
  end

  node.compact_child_nodes.each do |child|
    walk_constant_writes(child, qualified_prefix, default_scope, accumulator)
  end
end

.walk_def_nodes(node, qualified_prefix, in_singleton_class, accumulator) ⇒ Object 



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# File 'lib/rigor/inference/scope_indexer.rb', line 511

def walk_def_nodes(node, qualified_prefix, in_singleton_class, accumulator)
  return unless node.is_a?(Prism::Node)

  case node
  when Prism::ClassNode, Prism::ModuleNode
    name = qualified_name_for(node.constant_path)
    if name
      child_prefix = qualified_prefix + [name]
      walk_def_nodes(node.body, child_prefix, false, accumulator) if node.body
      return
    end
  when Prism::SingletonClassNode
    if node.body
      singleton_prefix = singleton_class_prefix(node, qualified_prefix)
      if singleton_prefix
        walk_def_nodes(node.body, singleton_prefix, true, accumulator)
        return
      end
    end
  when Prism::ConstantWriteNode
    if meta_new_block_body(node)
      child_prefix = qualified_prefix + [node.name.to_s]
      walk_def_nodes(meta_new_block_body(node), child_prefix, false, accumulator)
      return
    end
  when Prism::DefNode
    record_def_node(node, qualified_prefix, in_singleton_class, accumulator)
    return
  end

  node.compact_child_nodes.each do |child|
    walk_def_nodes(child, qualified_prefix, in_singleton_class, accumulator)
  end
end

.walk_method_visibilities(node, qualified_prefix, in_singleton_class, current_visibility, accumulator) ⇒ Object

rubocop:disable Metrics/CyclomaticComplexity, Metrics/MethodLength, Metrics/PerceivedComplexity, Metrics/AbcSize



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# File 'lib/rigor/inference/scope_indexer.rb', line 592

def walk_method_visibilities(node, qualified_prefix, in_singleton_class, current_visibility, accumulator)
  return current_visibility unless node.is_a?(Prism::Node)

  case node
  when Prism::ClassNode, Prism::ModuleNode
    name = qualified_name_for(node.constant_path)
    if name
      child_prefix = qualified_prefix + [name]
      walk_method_visibilities(node.body, child_prefix, false, :public, accumulator) if node.body
      return current_visibility
    end
  when Prism::SingletonClassNode
    if node.body
      singleton_prefix = singleton_class_prefix(node, qualified_prefix)
      if singleton_prefix
        walk_method_visibilities(node.body, singleton_prefix, true, :public, accumulator)
        return current_visibility
      end
    end
  when Prism::ConstantWriteNode
    if meta_new_block_body(node)
      child_prefix = qualified_prefix + [node.name.to_s]
      walk_method_visibilities(meta_new_block_body(node), child_prefix, false, :public, accumulator)
      return current_visibility
    end
  when Prism::DefNode
    record_def_visibility(node, qualified_prefix, in_singleton_class, current_visibility, accumulator)
    return current_visibility
  when Prism::CallNode
    updated = apply_visibility_call(node, qualified_prefix, current_visibility, accumulator)
    return updated unless updated.equal?(current_visibility)
  end

  # Statement-position StatementsNode preserves
  # left-to-right visibility flow; everything else
  # recurses with the entry visibility unchanged.
  if node.is_a?(Prism::StatementsNode)
    local_visibility = current_visibility
    node.compact_child_nodes.each do |child|
      local_visibility = walk_method_visibilities(child, qualified_prefix, in_singleton_class,
                                                  local_visibility, accumulator)
    end
  else
    node.compact_child_nodes.each do |child|
      walk_method_visibilities(child, qualified_prefix, in_singleton_class, current_visibility, accumulator)
    end
  end
  current_visibility
end

.walk_methods(node, qualified_prefix, in_singleton_class, accumulator) ⇒ Object

rubocop:disable Metrics/CyclomaticComplexity, Metrics/MethodLength



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# File 'lib/rigor/inference/scope_indexer.rb', line 364

def walk_methods(node, qualified_prefix, in_singleton_class, accumulator)
  return unless node.is_a?(Prism::Node)

  case node
  when Prism::ClassNode, Prism::ModuleNode
    name = qualified_name_for(node.constant_path)
    if name
      child_prefix = qualified_prefix + [name]
      walk_methods(node.body, child_prefix, false, accumulator) if node.body
      return
    end
  when Prism::SingletonClassNode
    if node.body
      singleton_prefix = singleton_class_prefix(node, qualified_prefix)
      if singleton_prefix
        walk_methods(node.body, singleton_prefix, true, accumulator)
        return
      end
    end
  when Prism::ConstantWriteNode
    if meta_new_block_body(node)
      child_prefix = qualified_prefix + [node.name.to_s]
      walk_methods(meta_new_block_body(node), child_prefix, false, accumulator)
      return
    end
  when Prism::DefNode
    record_def_method(node, qualified_prefix, in_singleton_class, accumulator)
    return
  when Prism::AliasMethodNode
    record_alias_method(node, qualified_prefix, in_singleton_class, accumulator)
    return
  when Prism::CallNode
    record_define_method(node, qualified_prefix, in_singleton_class, accumulator) if node.name == :define_method
  end

  node.compact_child_nodes.each do |child|
    walk_methods(child, qualified_prefix, in_singleton_class, accumulator)
  end
end