Module: MilkTea::Linter::LinterReleaseRules

Included in:
MilkTea::Linter
Defined in:
lib/milk_tea/tooling/linter/release_rules.rb

Instance Method Summary collapse

Instance Method Details

#_any_stmt?(stmts, &pred) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 554

def _any_stmt?(stmts, &pred)
  return false if stmts.nil?

  stmts.any? do |stmt|
    if pred.call(stmt)
      true
    else
      case stmt
      when AST::IfStmt
        stmt.branches.any? { |b| _any_stmt?(b.body, &pred) } ||
          _any_stmt?(stmt.else_body, &pred)
      when AST::WhileStmt then _any_stmt?(stmt.body, &pred)
      when AST::ForStmt then _any_stmt?(stmt.body, &pred)
      when AST::MatchStmt then stmt.arms.any? { |arm| _any_stmt?(arm.body, &pred) }
      when AST::UnsafeStmt then _any_stmt?(stmt.body, &pred)
      when AST::DeferStmt then stmt.body.is_a?(Array) && _any_stmt?(stmt.body, &pred)
      else false
      end
    end
  end
end

#_any_stmt_or_expr?(stmts, &pred) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 576

def _any_stmt_or_expr?(stmts, &pred)
  _any_stmt?(stmts) do |stmt|
    expr = extract_expr(stmt)
    expr && pred.call(expr)
  end
end

#_check_double_release_in_seq(stmts, result) ⇒ Object 



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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 349

def _check_double_release_in_seq(stmts, result)
  return if stmts.nil?

  scope_releases = Hash.new { |hash, key| hash[key] = [] }

  stmts.each do |stmt|
    expr = extract_expr(stmt)
    if expr && release_call_on_binding?(expr)
      name = expr.callee.receiver.name
      scope_releases[name] << extract_line(stmt)
    elsif expr && heap_release_call_on_name?(expr)
      name = heap_release_target_name(expr)
      scope_releases[name] << extract_line(stmt) if name
    end

    scope_releases.delete(stmt.target.name) if reassigns_owning_binding?(stmt)

    case stmt
    when AST::UnsafeStmt
      _check_double_release_in_seq(stmt.body, result)
    when AST::DeferStmt
      _check_double_release_in_seq(stmt.body, result) if stmt.body.is_a?(Array)
    end
  end

  scope_releases.each do |name, lines|
    result[name] = lines if lines.length > 1
  end
end

#_collect_heap_release_names(expr, result) ⇒ Object 



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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 176

def _collect_heap_release_names(expr, result)
  return if expr.nil?
  if heap_release_call_on_name?(expr)
    result << heap_release_target_name(expr)
  end
  case expr
  when AST::Call
    expr.arguments.each { |a| _collect_heap_release_names(a.value, result) }
    _collect_heap_release_names(expr.callee, result) if expr.callee.is_a?(AST::Call)
  when AST::BinaryOp
    _collect_heap_release_names(expr.left, result)
    _collect_heap_release_names(expr.right, result)
  when AST::UnaryOp
    _collect_heap_release_names(expr.operand, result)
  end
end

#_collect_own_released_names(stmts, result) ⇒ Object 



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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 145

def _collect_own_released_names(stmts, result)
  return if stmts.nil?
  stmts.each { |s| _collect_own_released_names_in_stmt(s, result) }
end

#_collect_own_released_names_in_stmt(stmt, result) ⇒ Object 



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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 150

def _collect_own_released_names_in_stmt(stmt, result)
  case stmt
  when AST::ExpressionStmt
    _collect_heap_release_names(stmt.expression, result)
  when AST::ReturnStmt
    _collect_heap_release_names(stmt.value, result) if stmt.value
  when AST::LocalDecl
    _collect_heap_release_names(stmt.value, result) if stmt.value
  when AST::Assignment
    _collect_heap_release_names(stmt.value, result)
  when AST::IfStmt
    stmt.branches.each { |b| _collect_own_released_names(b.body, result) }
    _collect_own_released_names(stmt.else_body, result) if stmt.else_body
  when AST::WhileStmt
    _collect_own_released_names(stmt.body, result)
  when AST::ForStmt
    _collect_own_released_names(stmt.body, result)
  when AST::MatchStmt
    stmt.arms.each { |arm| _collect_own_released_names(arm.body, result) }
  when AST::UnsafeStmt
    _collect_own_released_names(stmt.body, result)
  when AST::DeferStmt
    _collect_own_released_names(stmt.body, result) if stmt.body.is_a?(Array)
  end
end

#_collect_own_typed_locals(stmts, result) ⇒ Object 



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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 74

def _collect_own_typed_locals(stmts, result)
  return if stmts.nil?

  stmts.each do |stmt|
    case stmt
    when AST::LocalDecl
      type_name = resolve_local_own_pointer_type(stmt)
      if type_name
        result[stmt.name] = {
          line: stmt.line,
          column: stmt.column,
          type_name: type_name,
        }
      end
    when AST::IfStmt
      stmt.branches.each { |b| _collect_own_typed_locals(b.body, result) }
      _collect_own_typed_locals(stmt.else_body, result) if stmt.else_body
    when AST::WhileStmt
      _collect_own_typed_locals(stmt.body, result)
    when AST::ForStmt
      _collect_own_typed_locals(stmt.body, result)
    when AST::MatchStmt
      stmt.arms.each { |arm| _collect_own_typed_locals(arm.body, result) }
    when AST::UnsafeStmt
      _collect_own_typed_locals(stmt.body, result)
    when AST::DeferStmt
      _collect_own_typed_locals(stmt.body, result) if stmt.body.is_a?(Array)
    end
  end
end

#_collect_owning_locals(stmts, result) ⇒ Object 



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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 295

def _collect_owning_locals(stmts, result)
  return if stmts.nil?

  stmts.each do |stmt|
    case stmt
    when AST::LocalDecl
      type_name = resolve_local_owning_type(stmt)
      if type_name
        result[stmt.name] = {
          line: stmt.line,
          column: stmt.column,
          type_name: type_name,
        }
      end
    when AST::IfStmt
      stmt.branches.each { |b| _collect_owning_locals(b.body, result) }
      _collect_owning_locals(stmt.else_body, result) if stmt.else_body
    when AST::WhileStmt
      _collect_owning_locals(stmt.body, result)
    when AST::ForStmt
      _collect_owning_locals(stmt.body, result)
    when AST::MatchStmt
      stmt.arms.each { |arm| _collect_owning_locals(arm.body, result) }
    when AST::UnsafeStmt
      _collect_owning_locals(stmt.body, result)
    when AST::DeferStmt
      _collect_owning_locals(stmt.body, result) if stmt.body.is_a?(Array)
    end
  end
end

#_collect_released_names(stmts, result) ⇒ Object 



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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 481

def _collect_released_names(stmts, result)
  return if stmts.nil?
  stmts.each { |s| _collect_released_names_in_stmt(s, result) }
end

#_collect_released_names_in_expr(expr, result) ⇒ Object 



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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 512

def _collect_released_names_in_expr(expr, result)
  return if expr.nil?

  result << expr.callee.receiver.name if release_call_on_binding?(expr)
  if expr.is_a?(AST::Call) && expr.callee.is_a?(AST::Identifier) && expr.callee.name.start_with?("release_")
    result.merge(release_helper_binding_names(expr))
  end

  case expr
  when AST::Call
    expr.arguments.each { |a| _collect_released_names_in_expr(a.value, result) }
    _collect_released_names_in_expr(expr.callee, result)
  when AST::MemberAccess
    _collect_released_names_in_expr(expr.receiver, result)
  when AST::BinaryOp
    _collect_released_names_in_expr(expr.left, result)
    _collect_released_names_in_expr(expr.right, result)
  when AST::UnaryOp
    _collect_released_names_in_expr(expr.operand, result)
  end
end

#_collect_released_names_in_stmt(stmt, result) ⇒ Object 



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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 486

def _collect_released_names_in_stmt(stmt, result)
  case stmt
  when AST::ExpressionStmt
    _collect_released_names_in_expr(stmt.expression, result)
  when AST::ReturnStmt
    _collect_released_names_in_expr(stmt.value, result) if stmt.value
  when AST::LocalDecl
    _collect_released_names_in_expr(stmt.value, result) if stmt.value
  when AST::Assignment
    _collect_released_names_in_expr(stmt.value, result)
  when AST::IfStmt
    stmt.branches.each { |b| _collect_released_names(b.body, result) }
    _collect_released_names(stmt.else_body, result) if stmt.else_body
  when AST::WhileStmt
    _collect_released_names(stmt.body, result)
  when AST::ForStmt
    _collect_released_names(stmt.body, result)
  when AST::MatchStmt
    stmt.arms.each { |arm| _collect_released_names(arm.body, result) }
  when AST::UnsafeStmt
    _collect_released_names(stmt.body, result)
  when AST::DeferStmt
    _collect_released_names(stmt.body, result) if stmt.body.is_a?(Array)
  end
end

#_expr_contains_transfer?(expr, name) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 443

def _expr_contains_transfer?(expr, name)
  return false unless expr.is_a?(AST::Call)

  expr.arguments.any? do |arg|
    named = arg.is_a?(AST::Argument) && !arg.name.nil?
    argument_transfers?(arg.value, name, named)
  end
end

#_expr_has_release?(expr, name) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 674

def _expr_has_release?(expr, name)
  return false unless expr

  return true if release_call_on_binding?(expr) && expr.callee.receiver.name == name
  return true if expr.is_a?(AST::Call) && expr.callee.is_a?(AST::Identifier) &&
                 expr.callee.name.start_with?("release_") &&
                 release_helper_binding_names(expr).include?(name)

  case expr
  when AST::Call
    expr.arguments.any? { |a| _expr_has_release?(a.value, name) } ||
      _expr_has_release?(expr.callee, name)
  when AST::MemberAccess then _expr_has_release?(expr.receiver, name)
  when AST::BinaryOp
    _expr_has_release?(expr.left, name) || _expr_has_release?(expr.right, name)
  when AST::UnaryOp then _expr_has_release?(expr.operand, name)
  else false
  end
end

#all_own_released_names(stmts) ⇒ Object

── own release detection ──────────────────────────────────────



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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 139

def all_own_released_names(stmts)
  result = Set.new
  _collect_own_released_names(stmts, result)
  result
end

#all_released_names(stmts) ⇒ Object

── Shared AST walkers ────────────────────────────────────────────



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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 475

def all_released_names(stmts)
  result = Set.new
  _collect_released_names(stmts, result)
  result
end

#argument_transfers?(value, name, named) ⇒ Boolean

An identifier passed as a named argument transfers ownership (struct field initialization), even when wrapped in a pointer cast (e.g. handle_set_data(h, ptr<-state)). Nested calls are walked so queue.push(Foo(field = x)) recognizes the inner transfer.

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 456

def argument_transfers?(value, name, named)
  case value
  when AST::Identifier
    named && value.name == name
  when AST::PrefixCast
    inner = value.expression
    inner.is_a?(AST::Identifier) && inner.name == name
  when AST::Call
    value.arguments.any? do |arg|
      nested_named = arg.is_a?(AST::Argument) && !arg.name.nil?
      argument_transfers?(arg.value, name, nested_named)
    end
  else
    false
  end
end

#build_owning_type_set ⇒ Object 



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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 793

def build_owning_type_set
  set = Set.new
  return set unless @sema_facts

  all_methods = [@sema_facts.methods]
  (@imported_modules || {}).each_value do |mod_binding|
    all_methods << mod_binding.methods if mod_binding.respond_to?(:methods)
  end

  all_methods.compact.each do |methods_hash|
    methods_hash.each do |type, methods|
      next unless methods.is_a?(Hash) && methods.key?("release")
      set << type_base_name(type)
    end
  end
  set
end

#check_own_release_leaks(stmts) ⇒ Object

Check only own typed leaks (separate from struct-type leaks)



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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 45

def check_own_release_leaks(stmts)
  own_locals = own_typed_local_bindings(stmts)
  own_released = all_own_released_names(stmts)
  own_locals.reject { |name, _info| own_released.include?(name) || own_transferred?(stmts, name) }
end

#check_owning_release_double(stmts) ⇒ Object

── Simple sequential double-release ─────────────────────────────



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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 328

def check_owning_release_double(stmts)
  result = {}
  _check_double_release_in_seq(stmts, result)
  result
end

#check_owning_release_leaks(stmts) ⇒ Object

── Simple leak detection ──────────────────────────────────────────



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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 38

def check_owning_release_leaks(stmts)
  locals = owning_local_bindings(stmts)
  released = all_released_names(stmts)
  locals.reject { |name, _info| released.include?(name) || ownership_transferred?(stmts, name) }
end

#classify_cfg_nodes(graph, reachable_ids, name) ⇒ Object 



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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 632

def classify_cfg_nodes(graph, reachable_ids, name)
  releases = Set.new
  consumers = Set.new
  reassigns = Set.new

  graph.each_node do |node|
    next unless reachable_ids.include?(node.id)
    next unless node.statement

    is_defer = node.statement.is_a?(AST::DeferStmt)

    if release_call_in_stmt?(node.statement, name)
      consumers << node.id
      releases << node.id unless is_defer
    end

    if return_for_name?(node.statement, name) || struct_transfer_in_stmt?(node.statement, name)
      consumers << node.id
    end

    if node.kind == :assignment
      node.writes_info.each do |write|
        reassigns << node.id if write[:origin] == :assignment && write[:name] == name
      end
    end
  end

  [releases, consumers, reassigns]
end

#emit_owning_release_cfg_warnings(cfg_analysis, body) ⇒ Object

── CFG-based precision analysis ──────────────────────────────────



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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 585

def emit_owning_release_cfg_warnings(cfg_analysis, body)
  graph = cfg_analysis.graph
  reachable_ids = cfg_analysis.reachability.reachable_ids
          exit_kinds = %i[exit return break_exit continue_exit].to_set.freeze
  owning_locals = owning_local_bindings(body)
  return if owning_locals.empty?

  owning_locals.each do |name, info|
    decl_id = find_decl_node_id(graph, name)
    next unless decl_id && reachable_ids.include?(decl_id)

    releases, consumers, reassigns = classify_cfg_nodes(graph, reachable_ids, name)

    unless every_path_to_exit_has_consumer?(graph, decl_id, consumers, exit_kinds, reachable_ids)
      emit_owning_release_leak_warnings({ name => info })
    end

    releases.each do |rel_id|
      reachable_release = find_reachable_release(graph, rel_id, releases, reassigns, reachable_ids)
      next unless reachable_release

      node = graph.nodes[reachable_release]
      @warnings << Warning.new(
        path: @path,
        line: node&.line,
        column: nil,
        length: nil,
        code: "owning-release-double",
        message: "owning binding '#{name}' may be released more than once",
        severity: :warning,
        symbol_name: name,
      )
      break
    end
  end
end

#emit_owning_release_double_warnings(double_names_lines) ⇒ Object 



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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 334

def emit_owning_release_double_warnings(double_names_lines)
  double_names_lines.each do |name, lines|
    @warnings << Warning.new(
      path: @path,
      line: lines.last,
      column: nil,
      length: nil,
      code: "owning-release-double",
      message: "owning binding '#{name}' may be released more than once",
      severity: :warning,
      symbol_name: name,
    )
  end
end

#emit_owning_release_leak_warnings(leak_names) ⇒ Object 



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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 51

def emit_owning_release_leak_warnings(leak_names)
  leak_names.each do |name, info|
    @warnings << Warning.new(
      path: @path,
      line: info[:line],
      column: info[:column],
      length: name.length,
      code: "owning-release-leak",
      message: "owning binding '#{name}' of type '#{info[:type_name]}' is never released",
      severity: :warning,
      symbol_name: name,
    )
  end
end

#emit_owning_release_warnings(function_or_body) ⇒ Object

Entry point — called from visit_function and proc expr in full_tier mode.



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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 7

def emit_owning_release_warnings(function_or_body)
  body = function_or_body.is_a?(Array) ? function_or_body : function_or_body.body
  return unless body && !body.empty?

  cfg_available = false
  if @sema_facts
    cfg_available = begin
      analysis = profile_phase("rule.owning_release.cfg") { statement_flow_analysis(body) }
      analysis || false
    rescue StandardError
      false
    end
  end

  if cfg_available
    emit_owning_release_cfg_warnings(cfg_available, body)
  else
    # No CFG — emit struct-type leaks via simple pattern-matching
    leak_names = check_owning_release_leaks(body)
    emit_owning_release_leak_warnings(leak_names)
  end
  # Always run own[T] checks (AST-based, works with or without CFG)
  own_leaks = check_own_release_leaks(body)
  emit_owning_release_leak_warnings(own_leaks)

  double_names_lines = check_owning_release_double(body)
  emit_owning_release_double_warnings(double_names_lines)
end

#every_path_to_exit_has_consumer?(graph, start_id, consumers, exit_kinds, reachable_ids) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 705

def every_path_to_exit_has_consumer?(graph, start_id, consumers, exit_kinds, reachable_ids)
  visited = Set.new
  queue = (graph.nodes[start_id]&.succs || []).dup
  until queue.empty?
    nid = queue.shift
    next if visited.include?(nid)
    visited << nid
    next unless reachable_ids.include?(nid)

    node = graph.nodes[nid]
    next unless node

    if consumers.include?(nid)
      nil
    elsif exit_kinds.include?(node.kind)
      return false
    else
      node.succs.each { |s| queue << s }
    end
  end
  true
end

#extract_expr(stmt) ⇒ Object 



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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 768

def extract_expr(stmt)
  case stmt
  when AST::ExpressionStmt then stmt.expression
  when AST::ReturnStmt then stmt.value
  when AST::LocalDecl then stmt.value
  when AST::Assignment then stmt.value
  else nil
  end
end

#extract_initializer_type(expr) ⇒ Object 



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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 393

def extract_initializer_type(expr)
  return nil unless expr.is_a?(AST::Call)
  return nil unless expr.arguments.empty?

  callee = expr.callee
  method_name = case callee
                when AST::MemberAccess then callee.member
                when AST::Specialization
                  inner = callee.callee
                  inner.is_a?(AST::MemberAccess) ? inner.member : nil
                else nil
                end
  return nil unless %w[create with_capacity empty from_str].include?(method_name)

  receiver = case callee
             when AST::MemberAccess then callee.receiver
             when AST::Specialization then callee
             else nil
             end

  owning_type_from_receiver(receiver)
end

#extract_line(stmt) ⇒ Object 



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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 778

def extract_line(stmt)
  stmt.line
end

#find_decl_node_id(graph, name) ⇒ Object 



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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 622

def find_decl_node_id(graph, name)
  graph.each_node do |node|
    next unless node.kind == :local_decl
    node.writes_info.each do |write|
      return node.id if write[:origin] == :declaration && write[:name] == name
    end
  end
  nil
end

#find_reachable_release(graph, start_id, release_ids, reassign_ids, reachable_ids) ⇒ Object 



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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 728

def find_reachable_release(graph, start_id, release_ids, reassign_ids, reachable_ids)
  visited = Set.new
  queue = (graph.nodes[start_id]&.succs || []).dup
  until queue.empty?
    nid = queue.shift
    next if visited.include?(nid)
    visited << nid
    next unless reachable_ids.include?(nid)

    return nid if release_ids.include?(nid) && nid != start_id
    next if reassign_ids.include?(nid)

    node = graph.nodes[nid]
    next unless node

    queue.concat(node.succs)
  end
  nil
end

#heap_release_call_on_name?(expr) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 193

def heap_release_call_on_name?(expr)
  return false unless expr.is_a?(AST::Call)
  return false unless expr.callee.is_a?(AST::MemberAccess)
  return false unless %w[release release_and_null].include?(expr.callee.member)
  return false unless expr.arguments.length >= 1
  arg = expr.arguments.first
  return false unless arg.is_a?(AST::Argument)
  target_name = heap_release_target_name(expr)
  target_name && !target_name.empty?
end

#heap_release_target_name(expr) ⇒ Object 



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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 204

def heap_release_target_name(expr)
  return nil unless expr.is_a?(AST::Call)
  return nil unless expr.arguments.length >= 1
  # For multi-arg release (e.g. tracking.release(tracker, p)), find
  # the argument that names the released value by preferring the last
  # direct-identifier argument.
  released = nil
  expr.arguments.each do |arg|
    next unless arg.is_a?(AST::Argument)
    value = arg.value
    value = value.expression if value.is_a?(AST::UnsafeStmt)
    if value.is_a?(AST::Identifier)
      released = value.name
    elsif value.is_a?(AST::Call) && value.callee.is_a?(AST::Identifier) && value.callee.name == "ref_of"
      ref_arg = value.arguments.first
      if ref_arg.is_a?(AST::Argument) && ref_arg.value.is_a?(AST::Identifier)
        released = ref_arg.value.name
      end
    end
  end
  released
end

#is_heap_alloc_call?(expr) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 118

def is_heap_alloc_call?(expr)
  return false unless expr.is_a?(AST::Call)
  callee = expr.callee
  non_null_method_names = %w[must_alloc must_alloc_aligned
                             must_alloc_zeroed must_resize].to_set
  case callee
  when AST::MemberAccess
    callee.receiver.is_a?(AST::Identifier) &&
      non_null_method_names.include?(callee.member)
  when AST::Specialization
    inner = callee.callee
    inner.is_a?(AST::MemberAccess) &&
      inner.receiver.is_a?(AST::Identifier) &&
      non_null_method_names.include?(inner.member)
  else
    false
  end
end

#own_cast_in_unsafe?(expr, name) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 245

def own_cast_in_unsafe?(expr, name)
  case expr
  when AST::UnsafeExpr
    case expr.expression
    when AST::PrefixCast
      expr.expression.expression.is_a?(AST::Identifier) && expr.expression.expression.name == name
    end
  else
    false
  end
end

#own_struct_field_transfer?(expr, name) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 257

def own_struct_field_transfer?(expr, name)
  case expr
  when AST::Call
    expr.arguments.any? do |arg|
      next false unless arg.is_a?(AST::Argument)

      own_transfer_identifier?(arg.value, name)
    end
  when AST::PrefixCast
    own_transfer_identifier?(expr.expression, name)
  else
    false
  end
end

#own_transfer_identifier?(value, name) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 272

def own_transfer_identifier?(value, name)
  case value
  when AST::Identifier
    value.name == name
  when AST::PrefixCast
    own_transfer_identifier?(value.expression, name)
  when AST::Call
    value.arguments.any? do |arg|
      next false unless arg.is_a?(AST::Argument)

      own_transfer_identifier?(arg.value, name)
    end
  else
    false
  end
end

#own_transferred?(stmts, name) ⇒ Boolean

── own ownership transfer ─────────────────────────────────────

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 229

def own_transferred?(stmts, name)
  _any_stmt?(stmts) do |stmt|
    if stmt.is_a?(AST::ReturnStmt) && stmt.value.is_a?(AST::Identifier) && stmt.value.name == name
      true
    elsif (expr = extract_expr(stmt)) && own_struct_field_transfer?(expr, name)
      true
    elsif stmt.is_a?(AST::Assignment) && stmt.value.is_a?(AST::Identifier) && stmt.value.name == name
      true
    elsif stmt.is_a?(AST::ReturnStmt) && own_cast_in_unsafe?(stmt.value, name)
      true
    else
      false
    end
  end
end

#own_typed_local_bindings(stmts) ⇒ Object

── own typed local detection ──────────────────────────────────



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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 68

def own_typed_local_bindings(stmts)
  result = {}
  _collect_own_typed_locals(stmts, result)
  result
end

#ownership_transferred?(stmts, name) ⇒ Boolean

── Ownership transfer detection ──────────────────────────────────

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 427

def ownership_transferred?(stmts, name)
  returned_name?(stmts, name) || struct_field_transfer?(stmts, name)
end

#owning_base_name(qname) ⇒ Object 



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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 782

def owning_base_name(qname)
  last_dot = qname.rindex(".")
  last_dot ? qname[(last_dot + 1)..] : qname
end

#owning_local_bindings(stmts) ⇒ Object 



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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 289

def owning_local_bindings(stmts)
  result = {}
  _collect_owning_locals(stmts, result)
  result
end

#owning_type_by_name?(type_name) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 787

def owning_type_by_name?(type_name)
  return false unless type_name
  @owning_type_set ||= build_owning_type_set
  @owning_type_set.include?(type_name)
end

#owning_type_from_receiver(receiver) ⇒ Object 



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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 416

def owning_type_from_receiver(receiver)
  case receiver
  when AST::Identifier then owning_base_name(receiver.name)
  when AST::MemberAccess then owning_base_name(receiver.member)
  when AST::Specialization then owning_type_from_receiver(receiver.callee)
  else nil
  end
end

#reassigns_owning_binding?(stmt) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 759

def reassigns_owning_binding?(stmt)
  return false unless stmt.is_a?(AST::Assignment)
  return false unless stmt.target.is_a?(AST::Identifier)
  return false unless stmt.operator == "="

  @scopes.reverse_each { |scope| return true if scope.key?(stmt.target.name) }
  false
end

#release_call_in_stmt?(stmt, name) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 662

def release_call_in_stmt?(stmt, name)
  return false unless stmt

  # DeferStmt: block form `defer: …` (inline defers are a single-statement body)
  if stmt.is_a?(AST::DeferStmt)
    return stmt.body.is_a?(Array) && stmt.body.any? { |s| release_call_in_stmt?(s, name) }
  end

  expr = extract_expr(stmt)
  expr && _expr_has_release?(expr, name)
end

#release_call_on_binding?(expr) ⇒ Boolean

── Helpers ───────────────────────────────────────────────────────

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 750

def release_call_on_binding?(expr)
  return false unless expr.is_a?(AST::Call)
  return false unless expr.callee.is_a?(AST::MemberAccess)
  return false unless expr.callee.member == "release"
  return false unless expr.callee.receiver.is_a?(AST::Identifier)
  return false unless expr.arguments.empty?
  true
end

#release_helper_binding_names(expr) ⇒ Object

std convention: release_* helper functions take ownership of the bindings handed to them via ref_of/ptr_of, e.g. release_string_values(ref_of(values)). Treat those bindings as released so the leak rule understands the cleanup-helper idiom.



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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 538

def release_helper_binding_names(expr)
  names = Set.new
  expr.arguments.each do |arg|
    value = arg.respond_to?(:value) ? arg.value : nil
    next unless value.is_a?(AST::Call)
    next unless value.callee.is_a?(AST::Identifier)
    next unless %w[ref_of ptr_of].include?(value.callee.name)

    value.arguments.each do |inner|
      binding_name = inner.value
      names << binding_name.name if binding_name.is_a?(AST::Identifier)
    end
  end
  names
end

#resolve_local_own_pointer_type(decl) ⇒ Object 



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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 105

def resolve_local_own_pointer_type(decl)
  if is_heap_alloc_call?(decl.value)
    return "own[<inferred>]"
  end
  type = resolve_expr_type(decl.value) if decl.value
  return nil unless type
  return nil unless type.is_a?(MilkTea::Types::GenericInstance)
  return nil unless type.name == "own"
  type.to_s
rescue StandardError
  nil
end

#resolve_local_owning_type(decl) ⇒ Object

── Type resolution ────────────────────────────────────────────────



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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 381

def resolve_local_owning_type(decl)
  if decl.type && decl.type.is_a?(AST::TypeRef)
    base = owning_base_name(decl.type.name.to_s)
    return base if owning_type_by_name?(base)
  end
  if decl.value
    type_name = extract_initializer_type(decl.value)
    return type_name if type_name && owning_type_by_name?(type_name)
  end
  nil
end

#return_for_name?(stmt, name) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 694

def return_for_name?(stmt, name)
  stmt.is_a?(AST::ReturnStmt) &&
    stmt.value.is_a?(AST::Identifier) &&
    stmt.value.name == name
end

#returned_name?(stmts, name) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 431

def returned_name?(stmts, name)
  _any_stmt?(stmts) do |stmt|
    stmt.is_a?(AST::ReturnStmt) &&
      stmt.value.is_a?(AST::Identifier) &&
      stmt.value.name == name
  end
end

#struct_field_transfer?(stmts, name) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 439

def struct_field_transfer?(stmts, name)
  _any_stmt_or_expr?(stmts) { |expr| _expr_contains_transfer?(expr, name) }
end

#struct_transfer_in_stmt?(stmt, name) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 700

def struct_transfer_in_stmt?(stmt, name)
  expr = extract_expr(stmt)
  expr && _expr_contains_transfer?(expr, name)
end

#type_base_name(type) ⇒ Object 



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# File 'lib/milk_tea/tooling/linter/release_rules.rb', line 811

def type_base_name(type)
  return nil unless type
  return type.name.to_s if type.respond_to?(:name) && type.name
  type.to_s
end