# frozen_string_literal: true
module Prism
module Translation
class Parser
# A visitor that knows how to convert a prism syntax tree into the
# whitequark/parser gem's syntax tree.
class Compiler < ::Prism::Compiler
# Raised when the tree is malformed or there is a bug in the compiler.
class CompilationError < StandardError
end
# The Parser::Base instance that is being used to build the AST.
attr_reader :parser
# The Parser::Builders::Default instance that is being used to build the
# AST.
attr_reader :builder
# The Parser::Source::Buffer instance that is holding a reference to the
# source code.
attr_reader :source_buffer
# The offset cache that is used to map between byte and character
# offsets in the file.
attr_reader :offset_cache
# The types of values that can be forwarded in the current scope.
attr_reader :forwarding
# Whether or not the current node is in a destructure.
attr_reader :in_destructure
# Whether or not the current node is in a pattern.
attr_reader :in_pattern
# Initialize a new compiler with the given parser, offset cache, and
# options.
def initialize(parser, offset_cache, forwarding: [], in_destructure: false, in_pattern: false)
@parser = parser
@builder = parser.builder
@source_buffer = parser.source_buffer
@offset_cache = offset_cache
@forwarding = forwarding
@in_destructure = in_destructure
@in_pattern = in_pattern
end
# alias foo bar
# ^^^^^^^^^^^^^
def visit_alias_method_node(node)
builder.alias(token(node.keyword_loc), visit(node.new_name), visit(node.old_name))
end
# alias $foo $bar
# ^^^^^^^^^^^^^^^
def visit_alias_global_variable_node(node)
builder.alias(token(node.keyword_loc), visit(node.new_name), visit(node.old_name))
end
# foo => bar | baz
# ^^^^^^^^^
def visit_alternation_pattern_node(node)
builder.match_alt(visit(node.left), token(node.operator_loc), visit(node.right))
end
# a and b
# ^^^^^^^
def visit_and_node(node)
builder.logical_op(:and, visit(node.left), token(node.operator_loc), visit(node.right))
end
# []
# ^^
def visit_array_node(node)
builder.array(token(node.opening_loc), visit_all(node.elements), token(node.closing_loc))
end
# foo => [bar]
# ^^^^^
def visit_array_pattern_node(node)
elements = [*node.requireds]
elements << node.rest if !node.rest.nil? && !node.rest.is_a?(ImplicitRestNode)
elements.concat(node.posts)
visited = visit_all(elements)
if node.rest.is_a?(ImplicitRestNode)
visited[-1] = builder.match_with_trailing_comma(visited[-1], token(node.rest.location))
end
if node.constant
builder.const_pattern(visit(node.constant), token(node.opening_loc), builder.array_pattern(nil, visited, nil), token(node.closing_loc))
else
builder.array_pattern(token(node.opening_loc), visited, token(node.closing_loc))
end
end
# foo(bar)
# ^^^
def visit_arguments_node(node)
visit_all(node.arguments)
end
# { a: 1 }
# ^^^^
def visit_assoc_node(node)
if in_pattern
if node.value.is_a?(ImplicitNode)
if node.key.is_a?(SymbolNode)
builder.match_hash_var([node.key.unescaped, srange(node.key.location)])
else
builder.match_hash_var_from_str(token(node.key.opening_loc), visit_all(node.key.parts), token(node.key.closing_loc))
end
else
builder.pair_keyword([node.key.unescaped, srange(node.key.location)], visit(node.value))
end
elsif node.value.is_a?(ImplicitNode)
builder.pair_label([node.key.unescaped, srange(node.key.location)])
elsif node.operator_loc
builder.pair(visit(node.key), token(node.operator_loc), visit(node.value))
elsif node.key.is_a?(SymbolNode) && node.key.opening_loc.nil?
builder.pair_keyword([node.key.unescaped, srange(node.key.location)], visit(node.value))
else
parts =
if node.key.is_a?(SymbolNode)
[builder.string_internal([node.key.unescaped, srange(node.key.value_loc)])]
else
visit_all(node.key.parts)
end
builder.pair_quoted(token(node.key.opening_loc), parts, token(node.key.closing_loc), visit(node.value))
end
end
# def foo(**); bar(**); end
# ^^
#
# { **foo }
# ^^^^^
def visit_assoc_splat_node(node)
if node.value.nil? && forwarding.include?(:**)
builder.forwarded_kwrestarg(token(node.operator_loc))
else
builder.kwsplat(token(node.operator_loc), visit(node.value))
end
end
# $+
# ^^
def visit_back_reference_read_node(node)
builder.back_ref(token(node.location))
end
# begin end
# ^^^^^^^^^
def visit_begin_node(node)
rescue_bodies = []
if (rescue_clause = node.rescue_clause)
begin
find_start_offset = (rescue_clause.reference&.location || rescue_clause.exceptions.last&.location || rescue_clause.keyword_loc).end_offset
find_end_offset = (rescue_clause.statements&.location&.start_offset || rescue_clause.consequent&.location&.start_offset || (find_start_offset + 1))
rescue_bodies << builder.rescue_body(
token(rescue_clause.keyword_loc),
rescue_clause.exceptions.any? ? builder.array(nil, visit_all(rescue_clause.exceptions), nil) : nil,
token(rescue_clause.operator_loc),
visit(rescue_clause.reference),
srange_find(find_start_offset, find_end_offset, [";"]),
visit(rescue_clause.statements)
)
end until (rescue_clause = rescue_clause.consequent).nil?
end
begin_body =
builder.begin_body(
visit(node.statements),
rescue_bodies,
token(node.else_clause&.else_keyword_loc),
visit(node.else_clause),
token(node.ensure_clause&.ensure_keyword_loc),
visit(node.ensure_clause&.statements)
)
if node.begin_keyword_loc
builder.begin_keyword(token(node.begin_keyword_loc), begin_body, token(node.end_keyword_loc))
else
begin_body
end
end
# foo(&bar)
# ^^^^
def visit_block_argument_node(node)
builder.block_pass(token(node.operator_loc), visit(node.expression))
end
# foo { |; bar| }
# ^^^
def visit_block_local_variable_node(node)
builder.shadowarg(token(node.location))
end
# A block on a keyword or method call.
def visit_block_node(node)
raise CompilationError, "Cannot directly compile block nodes"
end
# def foo(&bar); end
# ^^^^
def visit_block_parameter_node(node)
builder.blockarg(token(node.operator_loc), token(node.name_loc))
end
# A block's parameters.
def visit_block_parameters_node(node)
[*visit(node.parameters)].concat(visit_all(node.locals))
end
# break
# ^^^^^
#
# break foo
# ^^^^^^^^^
def visit_break_node(node)
builder.keyword_cmd(:break, token(node.keyword_loc), nil, visit(node.arguments) || [], nil)
end
# foo
# ^^^
#
# foo.bar
# ^^^^^^^
#
# foo.bar() {}
# ^^^^^^^^^^^^
def visit_call_node(node)
name = node.name
arguments = node.arguments&.arguments || []
block = node.block
if block.is_a?(BlockArgumentNode)
arguments = [*arguments, block]
block = nil
end
if node.call_operator_loc.nil?
case name
when :!
return visit_block(builder.not_op(token(node.message_loc), token(node.opening_loc), visit(node.receiver), token(node.closing_loc)), block)
when :[]
return visit_block(builder.index(visit(node.receiver), token(node.opening_loc), visit_all(arguments), token(node.closing_loc)), block)
when :[]=
if node.message != "[]=" && node.arguments && block.nil? && !node.safe_navigation?
return visit_block(
builder.assign(
builder.index_asgn(
visit(node.receiver),
token(node.opening_loc),
visit_all(node.arguments.arguments[...-1]),
token(node.closing_loc),
),
srange_find(node.message_loc.end_offset, node.arguments.arguments.last.location.start_offset, ["="]),
visit(node.arguments.arguments.last)
),
block
)
end
end
end
message_loc = node.message_loc
call_operator_loc = node.call_operator_loc
call_operator = [{ "." => :dot, "&." => :anddot, "::" => "::" }.fetch(call_operator_loc.slice), srange(call_operator_loc)] if call_operator_loc
visit_block(
if name.end_with?("=") && !message_loc.slice.end_with?("=") && node.arguments && block.nil?
builder.assign(
builder.attr_asgn(visit(node.receiver), call_operator, token(message_loc)),
srange_find(message_loc.end_offset, node.arguments.location.start_offset, ["="]),
visit(node.arguments.arguments.last)
)
else
builder.call_method(
visit(node.receiver),
call_operator,
message_loc ? [node.name, srange(message_loc)] : nil,
token(node.opening_loc),
visit_all(arguments),
token(node.closing_loc)
)
end,
block
)
end
# foo.bar += baz
# ^^^^^^^^^^^^^^^
def visit_call_operator_write_node(node)
call_operator_loc = node.call_operator_loc
builder.op_assign(
builder.call_method(
visit(node.receiver),
call_operator_loc.nil? ? nil : [{ "." => :dot, "&." => :anddot, "::" => "::" }.fetch(call_operator_loc.slice), srange(call_operator_loc)],
node.message_loc ? [node.read_name, srange(node.message_loc)] : nil,
nil,
[],
nil
),
[node.operator_loc.slice.chomp("="), srange(node.operator_loc)],
visit(node.value)
)
end
# foo.bar &&= baz
# ^^^^^^^^^^^^^^^
alias visit_call_and_write_node visit_call_operator_write_node
# foo.bar ||= baz
# ^^^^^^^^^^^^^^^
alias visit_call_or_write_node visit_call_operator_write_node
# foo.bar, = 1
# ^^^^^^^
def visit_call_target_node(node)
call_operator_loc = node.call_operator_loc
builder.attr_asgn(
visit(node.receiver),
call_operator_loc.nil? ? nil : [{ "." => :dot, "&." => :anddot, "::" => "::" }.fetch(call_operator_loc.slice), srange(call_operator_loc)],
token(node.message_loc)
)
end
# foo => bar => baz
# ^^^^^^^^^^
def visit_capture_pattern_node(node)
builder.match_as(visit(node.value), token(node.operator_loc), visit(node.target))
end
# case foo; when bar; end
# ^^^^^^^^^^^^^^^^^^^^^^^
def visit_case_node(node)
builder.case(
token(node.case_keyword_loc),
visit(node.predicate),
visit_all(node.conditions),
token(node.consequent&.else_keyword_loc),
visit(node.consequent),
token(node.end_keyword_loc)
)
end
# case foo; in bar; end
# ^^^^^^^^^^^^^^^^^^^^^
def visit_case_match_node(node)
builder.case_match(
token(node.case_keyword_loc),
visit(node.predicate),
visit_all(node.conditions),
token(node.consequent&.else_keyword_loc),
visit(node.consequent),
token(node.end_keyword_loc)
)
end
# class Foo; end
# ^^^^^^^^^^^^^^
def visit_class_node(node)
builder.def_class(
token(node.class_keyword_loc),
visit(node.constant_path),
token(node.inheritance_operator_loc),
visit(node.superclass),
node.body&.accept(copy_compiler(forwarding: [])),
token(node.end_keyword_loc)
)
end
# @@foo
# ^^^^^
def visit_class_variable_read_node(node)
builder.cvar(token(node.location))
end
# @@foo = 1
# ^^^^^^^^^
#
# @@foo, @@bar = 1
# ^^^^^ ^^^^^
def visit_class_variable_write_node(node)
builder.assign(
builder.assignable(builder.cvar(token(node.name_loc))),
token(node.operator_loc),
visit(node.value)
)
end
# @@foo += bar
# ^^^^^^^^^^^^
def visit_class_variable_operator_write_node(node)
builder.op_assign(
builder.assignable(builder.cvar(token(node.name_loc))),
[node.operator_loc.slice.chomp("="), srange(node.operator_loc)],
visit(node.value)
)
end
# @@foo &&= bar
# ^^^^^^^^^^^^^
alias visit_class_variable_and_write_node visit_class_variable_operator_write_node
# @@foo ||= bar
# ^^^^^^^^^^^^^
alias visit_class_variable_or_write_node visit_class_variable_operator_write_node
# @@foo, = bar
# ^^^^^
def visit_class_variable_target_node(node)
builder.assignable(builder.cvar(token(node.location)))
end
# Foo
# ^^^
def visit_constant_read_node(node)
builder.const([node.name, srange(node.location)])
end
# Foo = 1
# ^^^^^^^
#
# Foo, Bar = 1
# ^^^ ^^^
def visit_constant_write_node(node)
builder.assign(builder.assignable(builder.const([node.name, srange(node.name_loc)])), token(node.operator_loc), visit(node.value))
end
# Foo += bar
# ^^^^^^^^^^^
def visit_constant_operator_write_node(node)
builder.op_assign(
builder.assignable(builder.const([node.name, srange(node.name_loc)])),
[node.operator_loc.slice.chomp("="), srange(node.operator_loc)],
visit(node.value)
)
end
# Foo &&= bar
# ^^^^^^^^^^^^
alias visit_constant_and_write_node visit_constant_operator_write_node
# Foo ||= bar
# ^^^^^^^^^^^^
alias visit_constant_or_write_node visit_constant_operator_write_node
# Foo, = bar
# ^^^
def visit_constant_target_node(node)
builder.assignable(builder.const([node.name, srange(node.location)]))
end
# Foo::Bar
# ^^^^^^^^
def visit_constant_path_node(node)
if node.parent.nil?
builder.const_global(
token(node.delimiter_loc),
[node.child.name, srange(node.child.location)]
)
else
builder.const_fetch(
visit(node.parent),
token(node.delimiter_loc),
[node.child.name, srange(node.child.location)]
)
end
end
# Foo::Bar = 1
# ^^^^^^^^^^^^
#
# Foo::Foo, Bar::Bar = 1
# ^^^^^^^^ ^^^^^^^^
def visit_constant_path_write_node(node)
builder.assign(
builder.assignable(visit(node.target)),
token(node.operator_loc),
visit(node.value)
)
end
# Foo::Bar += baz
# ^^^^^^^^^^^^^^^
def visit_constant_path_operator_write_node(node)
builder.op_assign(
builder.assignable(visit(node.target)),
[node.operator_loc.slice.chomp("="), srange(node.operator_loc)],
visit(node.value)
)
end
# Foo::Bar &&= baz
# ^^^^^^^^^^^^^^^^
alias visit_constant_path_and_write_node visit_constant_path_operator_write_node
# Foo::Bar ||= baz
# ^^^^^^^^^^^^^^^^
alias visit_constant_path_or_write_node visit_constant_path_operator_write_node
# Foo::Bar, = baz
# ^^^^^^^^
def visit_constant_path_target_node(node)
builder.assignable(visit_constant_path_node(node))
end
# def foo; end
# ^^^^^^^^^^^^
#
# def self.foo; end
# ^^^^^^^^^^^^^^^^^
def visit_def_node(node)
if node.equal_loc
if node.receiver
builder.def_endless_singleton(
token(node.def_keyword_loc),
visit(node.receiver.is_a?(ParenthesesNode) ? node.receiver.body : node.receiver),
token(node.operator_loc),
token(node.name_loc),
builder.args(token(node.lparen_loc), visit(node.parameters) || [], token(node.rparen_loc), false),
token(node.equal_loc),
node.body&.accept(copy_compiler(forwarding: find_forwarding(node.parameters)))
)
else
builder.def_endless_method(
token(node.def_keyword_loc),
token(node.name_loc),
builder.args(token(node.lparen_loc), visit(node.parameters) || [], token(node.rparen_loc), false),
token(node.equal_loc),
node.body&.accept(copy_compiler(forwarding: find_forwarding(node.parameters)))
)
end
elsif node.receiver
builder.def_singleton(
token(node.def_keyword_loc),
visit(node.receiver.is_a?(ParenthesesNode) ? node.receiver.body : node.receiver),
token(node.operator_loc),
token(node.name_loc),
builder.args(token(node.lparen_loc), visit(node.parameters) || [], token(node.rparen_loc), false),
node.body&.accept(copy_compiler(forwarding: find_forwarding(node.parameters))),
token(node.end_keyword_loc)
)
else
builder.def_method(
token(node.def_keyword_loc),
token(node.name_loc),
builder.args(token(node.lparen_loc), visit(node.parameters) || [], token(node.rparen_loc), false),
node.body&.accept(copy_compiler(forwarding: find_forwarding(node.parameters))),
token(node.end_keyword_loc)
)
end
end
# defined? a
# ^^^^^^^^^^
#
# defined?(a)
# ^^^^^^^^^^^
def visit_defined_node(node)
builder.keyword_cmd(
:defined?,
token(node.keyword_loc),
token(node.lparen_loc),
[visit(node.value)],
token(node.rparen_loc)
)
end
# if foo then bar else baz end
# ^^^^^^^^^^^^
def visit_else_node(node)
visit(node.statements)
end
# "foo #{bar}"
# ^^^^^^
def visit_embedded_statements_node(node)
builder.begin(
token(node.opening_loc),
visit(node.statements),
token(node.closing_loc)
)
end
# "foo #@bar"
# ^^^^^
def visit_embedded_variable_node(node)
visit(node.variable)
end
# begin; foo; ensure; bar; end
# ^^^^^^^^^^^^
def visit_ensure_node(node)
raise CompilationError, "Cannot directly compile ensure nodes"
end
# false
# ^^^^^
def visit_false_node(node)
builder.false(token(node.location))
end
# foo => [*, bar, *]
# ^^^^^^^^^^^
def visit_find_pattern_node(node)
elements = [node.left, *node.requireds, node.right]
if node.constant
builder.const_pattern(visit(node.constant), token(node.opening_loc), builder.find_pattern(nil, visit_all(elements), nil), token(node.closing_loc))
else
builder.find_pattern(token(node.opening_loc), visit_all(elements), token(node.closing_loc))
end
end
# 1.0
# ^^^
def visit_float_node(node)
visit_numeric(node, builder.float([node.value, srange(node.location)]))
end
# for foo in bar do end
# ^^^^^^^^^^^^^^^^^^^^^
def visit_for_node(node)
builder.for(
token(node.for_keyword_loc),
visit(node.index),
token(node.in_keyword_loc),
visit(node.collection),
if node.do_keyword_loc
token(node.do_keyword_loc)
else
srange_find(node.collection.location.end_offset, (node.statements&.location || node.end_keyword_loc).start_offset, [";"])
end,
visit(node.statements),
token(node.end_keyword_loc)
)
end
# def foo(...); bar(...); end
# ^^^
def visit_forwarding_arguments_node(node)
builder.forwarded_args(token(node.location))
end
# def foo(...); end
# ^^^
def visit_forwarding_parameter_node(node)
builder.forward_arg(token(node.location))
end
# super
# ^^^^^
#
# super {}
# ^^^^^^^^
def visit_forwarding_super_node(node)
visit_block(
builder.keyword_cmd(
:zsuper,
["super", srange_offsets(node.location.start_offset, node.location.start_offset + 5)]
),
node.block
)
end
# $foo
# ^^^^
def visit_global_variable_read_node(node)
builder.gvar(token(node.location))
end
# $foo = 1
# ^^^^^^^^
#
# $foo, $bar = 1
# ^^^^ ^^^^
def visit_global_variable_write_node(node)
builder.assign(
builder.assignable(builder.gvar(token(node.name_loc))),
token(node.operator_loc),
visit(node.value)
)
end
# $foo += bar
# ^^^^^^^^^^^
def visit_global_variable_operator_write_node(node)
builder.op_assign(
builder.assignable(builder.gvar(token(node.name_loc))),
[node.operator_loc.slice.chomp("="), srange(node.operator_loc)],
visit(node.value)
)
end
# $foo &&= bar
# ^^^^^^^^^^^^
alias visit_global_variable_and_write_node visit_global_variable_operator_write_node
# $foo ||= bar
# ^^^^^^^^^^^^
alias visit_global_variable_or_write_node visit_global_variable_operator_write_node
# $foo, = bar
# ^^^^
def visit_global_variable_target_node(node)
builder.assignable(builder.gvar([node.slice, srange(node.location)]))
end
# {}
# ^^
def visit_hash_node(node)
builder.associate(
token(node.opening_loc),
visit_all(node.elements),
token(node.closing_loc)
)
end
# foo => {}
# ^^
def visit_hash_pattern_node(node)
elements = [*node.elements, *node.rest]
if node.constant
builder.const_pattern(visit(node.constant), token(node.opening_loc), builder.hash_pattern(nil, visit_all(elements), nil), token(node.closing_loc))
else
builder.hash_pattern(token(node.opening_loc), visit_all(elements), token(node.closing_loc))
end
end
# if foo then bar end
# ^^^^^^^^^^^^^^^^^^^
#
# bar if foo
# ^^^^^^^^^^
#
# foo ? bar : baz
# ^^^^^^^^^^^^^^^
def visit_if_node(node)
if !node.if_keyword_loc
builder.ternary(
visit(node.predicate),
token(node.then_keyword_loc),
visit(node.statements),
token(node.consequent.else_keyword_loc),
visit(node.consequent)
)
elsif node.if_keyword_loc.start_offset == node.location.start_offset
builder.condition(
token(node.if_keyword_loc),
visit(node.predicate),
if node.then_keyword_loc
token(node.then_keyword_loc)
else
srange_find(node.predicate.location.end_offset, (node.statements&.location || node.consequent&.location || node.end_keyword_loc).start_offset, [";"])
end,
visit(node.statements),
case node.consequent
when IfNode
token(node.consequent.if_keyword_loc)
when ElseNode
token(node.consequent.else_keyword_loc)
end,
visit(node.consequent),
if node.if_keyword != "elsif"
token(node.end_keyword_loc)
end
)
else
builder.condition_mod(
visit(node.statements),
visit(node.consequent),
token(node.if_keyword_loc),
visit(node.predicate)
)
end
end
# 1i
def visit_imaginary_node(node)
visit_numeric(node, builder.complex([node.value, srange(node.location)]))
end
# { foo: }
# ^^^^
def visit_implicit_node(node)
raise CompilationError, "Cannot directly compile implicit nodes"
end
# foo { |bar,| }
# ^
def visit_implicit_rest_node(node)
raise CompilationError, "Cannot compile implicit rest nodes"
end
# case foo; in bar; end
# ^^^^^^^^^^^^^^^^^^^^^
def visit_in_node(node)
pattern = nil
guard = nil
case node.pattern
when IfNode
pattern = within_pattern { |compiler| node.pattern.statements.accept(compiler) }
guard = builder.if_guard(token(node.pattern.if_keyword_loc), visit(node.pattern.predicate))
when UnlessNode
pattern = within_pattern { |compiler| node.pattern.statements.accept(compiler) }
guard = builder.unless_guard(token(node.pattern.keyword_loc), visit(node.pattern.predicate))
else
pattern = within_pattern { |compiler| node.pattern.accept(compiler) }
end
builder.in_pattern(
token(node.in_loc),
pattern,
guard,
srange_find(node.pattern.location.end_offset, node.statements&.location&.start_offset || node.location.end_offset, [";", "then"]),
visit(node.statements)
)
end
# foo[bar] += baz
# ^^^^^^^^^^^^^^^
def visit_index_operator_write_node(node)
arguments = node.arguments&.arguments || []
arguments << node.block if node.block
builder.op_assign(
builder.index(
visit(node.receiver),
token(node.opening_loc),
visit_all(arguments),
token(node.closing_loc)
),
[node.operator_loc.slice.chomp("="), srange(node.operator_loc)],
visit(node.value)
)
end
# foo[bar] &&= baz
# ^^^^^^^^^^^^^^^^
alias visit_index_and_write_node visit_index_operator_write_node
# foo[bar] ||= baz
# ^^^^^^^^^^^^^^^^
alias visit_index_or_write_node visit_index_operator_write_node
# foo[bar], = 1
# ^^^^^^^^
def visit_index_target_node(node)
builder.index_asgn(
visit(node.receiver),
token(node.opening_loc),
visit_all(node.arguments.arguments),
token(node.closing_loc),
)
end
# @foo
# ^^^^
def visit_instance_variable_read_node(node)
builder.ivar(token(node.location))
end
# @foo = 1
# ^^^^^^^^
#
# @foo, @bar = 1
# ^^^^ ^^^^
def visit_instance_variable_write_node(node)
builder.assign(
builder.assignable(builder.ivar(token(node.name_loc))),
token(node.operator_loc),
visit(node.value)
)
end
# @foo += bar
# ^^^^^^^^^^^
def visit_instance_variable_operator_write_node(node)
builder.op_assign(
builder.assignable(builder.ivar(token(node.name_loc))),
[node.operator_loc.slice.chomp("="), srange(node.operator_loc)],
visit(node.value)
)
end
# @foo &&= bar
# ^^^^^^^^^^^^
alias visit_instance_variable_and_write_node visit_instance_variable_operator_write_node
# @foo ||= bar
# ^^^^^^^^^^^^
alias visit_instance_variable_or_write_node visit_instance_variable_operator_write_node
# @foo, = bar
# ^^^^
def visit_instance_variable_target_node(node)
builder.assignable(builder.ivar(token(node.location)))
end
# 1
# ^
def visit_integer_node(node)
visit_numeric(node, builder.integer([node.value, srange(node.location)]))
end
# /foo #{bar}/
# ^^^^^^^^^^^^
def visit_interpolated_regular_expression_node(node)
builder.regexp_compose(
token(node.opening_loc),
visit_all(node.parts),
[node.closing[0], srange_offsets(node.closing_loc.start_offset, node.closing_loc.start_offset + 1)],
builder.regexp_options([node.closing[1..], srange_offsets(node.closing_loc.start_offset + 1, node.closing_loc.end_offset)])
)
end
# if /foo #{bar}/ then end
# ^^^^^^^^^^^^
alias visit_interpolated_match_last_line_node visit_interpolated_regular_expression_node
# "foo #{bar}"
# ^^^^^^^^^^^^
def visit_interpolated_string_node(node)
if node.opening&.start_with?("<<")
children, closing = visit_heredoc(node)
builder.string_compose(token(node.opening_loc), children, closing)
else
builder.string_compose(
token(node.opening_loc),
visit_all(node.parts),
token(node.closing_loc)
)
end
end
# :"foo #{bar}"
# ^^^^^^^^^^^^^
def visit_interpolated_symbol_node(node)
builder.symbol_compose(
token(node.opening_loc),
visit_all(node.parts),
token(node.closing_loc)
)
end
# `foo #{bar}`
# ^^^^^^^^^^^^
def visit_interpolated_x_string_node(node)
if node.opening.start_with?("<<")
children, closing = visit_heredoc(node)
builder.xstring_compose(token(node.opening_loc), children, closing)
else
builder.xstring_compose(
token(node.opening_loc),
visit_all(node.parts),
token(node.closing_loc)
)
end
end
# foo(bar: baz)
# ^^^^^^^^
def visit_keyword_hash_node(node)
builder.associate(nil, visit_all(node.elements), nil)
end
# def foo(**bar); end
# ^^^^^
#
# def foo(**); end
# ^^
def visit_keyword_rest_parameter_node(node)
builder.kwrestarg(
token(node.operator_loc),
node.name ? [node.name, srange(node.name_loc)] : nil
)
end
# -> {}
def visit_lambda_node(node)
parameters = node.parameters
builder.block(
builder.call_lambda(token(node.operator_loc)),
[node.opening, srange(node.opening_loc)],
if parameters.nil?
builder.args(nil, [], nil, false)
elsif node.parameters.is_a?(NumberedParametersNode)
visit(node.parameters)
else
builder.args(
token(node.parameters.opening_loc),
visit(node.parameters),
token(node.parameters.closing_loc),
false
)
end,
node.body&.accept(copy_compiler(forwarding: parameters.is_a?(NumberedParametersNode) ? [] : find_forwarding(parameters&.parameters))),
[node.closing, srange(node.closing_loc)]
)
end
# foo
# ^^^
def visit_local_variable_read_node(node)
builder.ident([node.name, srange(node.location)]).updated(:lvar)
end
# foo = 1
# ^^^^^^^
#
# foo, bar = 1
# ^^^ ^^^
def visit_local_variable_write_node(node)
builder.assign(
builder.assignable(builder.ident(token(node.name_loc))),
token(node.operator_loc),
visit(node.value)
)
end
# foo += bar
# ^^^^^^^^^^
def visit_local_variable_operator_write_node(node)
builder.op_assign(
builder.assignable(builder.ident(token(node.name_loc))),
[node.operator_loc.slice.chomp("="), srange(node.operator_loc)],
visit(node.value)
)
end
# foo &&= bar
# ^^^^^^^^^^^
alias visit_local_variable_and_write_node visit_local_variable_operator_write_node
# foo ||= bar
# ^^^^^^^^^^^
alias visit_local_variable_or_write_node visit_local_variable_operator_write_node
# foo, = bar
# ^^^
def visit_local_variable_target_node(node)
if in_pattern
builder.assignable(builder.match_var([node.name, srange(node.location)]))
else
builder.assignable(builder.ident(token(node.location)))
end
end
# foo in bar
# ^^^^^^^^^^
if RUBY_VERSION >= "3.0"
def visit_match_predicate_node(node)
builder.match_pattern_p(
visit(node.value),
token(node.operator_loc),
within_pattern { |compiler| node.pattern.accept(compiler) }
)
end
else
def visit_match_predicate_node(node)
builder.match_pattern(
visit(node.value),
token(node.operator_loc),
within_pattern { |compiler| node.pattern.accept(compiler) }
)
end
end
# foo => bar
# ^^^^^^^^^^
def visit_match_required_node(node)
builder.match_pattern(
visit(node.value),
token(node.operator_loc),
within_pattern { |compiler| node.pattern.accept(compiler) }
)
end
# /(?<foo>foo)/ =~ bar
# ^^^^^^^^^^^^^^^^^^^^
def visit_match_write_node(node)
builder.match_op(
visit(node.call.receiver),
token(node.call.message_loc),
visit(node.call.arguments.arguments.first)
)
end
# A node that is missing from the syntax tree. This is only used in the
# case of a syntax error. The parser gem doesn't have such a concept, so
# we invent our own here.
def visit_missing_node(node)
::AST::Node.new(:missing, [], location: ::Parser::Source::Map.new(srange(node.location)))
end
# module Foo; end
# ^^^^^^^^^^^^^^^
def visit_module_node(node)
builder.def_module(
token(node.module_keyword_loc),
visit(node.constant_path),
node.body&.accept(copy_compiler(forwarding: [])),
token(node.end_keyword_loc)
)
end
# foo, bar = baz
# ^^^^^^^^
def visit_multi_target_node(node)
elements = [*node.lefts]
elements << node.rest if !node.rest.nil? && !node.rest.is_a?(ImplicitRestNode)
elements.concat(node.rights)
builder.multi_lhs(
token(node.lparen_loc),
visit_all(elements),
token(node.rparen_loc)
)
end
# foo, bar = baz
# ^^^^^^^^^^^^^^
def visit_multi_write_node(node)
elements = [*node.lefts]
elements << node.rest if !node.rest.nil? && !node.rest.is_a?(ImplicitRestNode)
elements.concat(node.rights)
builder.multi_assign(
builder.multi_lhs(
token(node.lparen_loc),
visit_all(elements),
token(node.rparen_loc)
),
token(node.operator_loc),
visit(node.value)
)
end
# next
# ^^^^
#
# next foo
# ^^^^^^^^
def visit_next_node(node)
builder.keyword_cmd(
:next,
token(node.keyword_loc),
nil,
visit(node.arguments) || [],
nil
)
end
# nil
# ^^^
def visit_nil_node(node)
builder.nil(token(node.location))
end
# def foo(**nil); end
# ^^^^^
def visit_no_keywords_parameter_node(node)
if in_pattern
builder.match_nil_pattern(token(node.operator_loc), token(node.keyword_loc))
else
builder.kwnilarg(token(node.operator_loc), token(node.keyword_loc))
end
end
# -> { _1 + _2 }
# ^^^^^^^^^^^^^^
def visit_numbered_parameters_node(node)
builder.numargs(node.maximum)
end
# $1
# ^^
def visit_numbered_reference_read_node(node)
builder.nth_ref([node.number, srange(node.location)])
end
# def foo(bar: baz); end
# ^^^^^^^^
def visit_optional_keyword_parameter_node(node)
builder.kwoptarg([node.name, srange(node.name_loc)], visit(node.value))
end
# def foo(bar = 1); end
# ^^^^^^^
def visit_optional_parameter_node(node)
builder.optarg(token(node.name_loc), token(node.operator_loc), visit(node.value))
end
# a or b
# ^^^^^^
def visit_or_node(node)
builder.logical_op(:or, visit(node.left), token(node.operator_loc), visit(node.right))
end
# def foo(bar, *baz); end
# ^^^^^^^^^
def visit_parameters_node(node)
params = []
if node.requireds.any?
node.requireds.each do |required|
if required.is_a?(RequiredParameterNode)
params << visit(required)
else
compiler = copy_compiler(in_destructure: true)
params << required.accept(compiler)
end
end
end
params.concat(visit_all(node.optionals)) if node.optionals.any?
params << visit(node.rest) if !node.rest.nil? && !node.rest.is_a?(ImplicitRestNode)
if node.posts.any?
node.posts.each do |post|
if post.is_a?(RequiredParameterNode)
params << visit(post)
else
compiler = copy_compiler(in_destructure: true)
params << post.accept(compiler)
end
end
end
params.concat(visit_all(node.keywords)) if node.keywords.any?
params << visit(node.keyword_rest) if !node.keyword_rest.nil?
params << visit(node.block) if !node.block.nil?
params
end
# ()
# ^^
#
# (1)
# ^^^
def visit_parentheses_node(node)
builder.begin(
token(node.opening_loc),
visit(node.body),
token(node.closing_loc)
)
end
# foo => ^(bar)
# ^^^^^^
def visit_pinned_expression_node(node)
builder.pin(token(node.operator_loc), visit(node.expression))
end
# foo = 1 and bar => ^foo
# ^^^^
def visit_pinned_variable_node(node)
builder.pin(token(node.operator_loc), visit(node.variable))
end
# END {}
def visit_post_execution_node(node)
builder.postexe(
token(node.keyword_loc),
token(node.opening_loc),
visit(node.statements),
token(node.closing_loc)
)
end
# BEGIN {}
def visit_pre_execution_node(node)
builder.preexe(
token(node.keyword_loc),
token(node.opening_loc),
visit(node.statements),
token(node.closing_loc)
)
end
# The top-level program node.
def visit_program_node(node)
visit(node.statements)
end
# 0..5
# ^^^^
def visit_range_node(node)
if node.exclude_end?
builder.range_exclusive(
visit(node.left),
token(node.operator_loc),
visit(node.right)
)
else
builder.range_inclusive(
visit(node.left),
token(node.operator_loc),
visit(node.right)
)
end
end
# if foo .. bar; end
# ^^^^^^^^^^
alias visit_flip_flop_node visit_range_node
# 1r
# ^^
def visit_rational_node(node)
visit_numeric(node, builder.rational([node.value, srange(node.location)]))
end
# redo
# ^^^^
def visit_redo_node(node)
builder.keyword_cmd(:redo, token(node.location))
end
# /foo/
# ^^^^^
def visit_regular_expression_node(node)
builder.regexp_compose(
token(node.opening_loc),
[builder.string_internal(token(node.content_loc))],
[node.closing[0], srange_offsets(node.closing_loc.start_offset, node.closing_loc.start_offset + 1)],
builder.regexp_options([node.closing[1..], srange_offsets(node.closing_loc.start_offset + 1, node.closing_loc.end_offset)])
)
end
# if /foo/ then end
# ^^^^^
alias visit_match_last_line_node visit_regular_expression_node
# def foo(bar:); end
# ^^^^
def visit_required_keyword_parameter_node(node)
builder.kwarg([node.name, srange(node.name_loc)])
end
# def foo(bar); end
# ^^^
def visit_required_parameter_node(node)
builder.arg(token(node.location))
end
# foo rescue bar
# ^^^^^^^^^^^^^^
def visit_rescue_modifier_node(node)
builder.begin_body(
visit(node.expression),
[
builder.rescue_body(
token(node.keyword_loc),
nil,
nil,
nil,
nil,
visit(node.rescue_expression)
)
]
)
end
# begin; rescue; end
# ^^^^^^^
def visit_rescue_node(node)
raise CompilationError, "Cannot directly compile rescue nodes"
end
# def foo(*bar); end
# ^^^^
#
# def foo(*); end
# ^
def visit_rest_parameter_node(node)
builder.restarg(token(node.operator_loc), token(node.name_loc))
end
# retry
# ^^^^^
def visit_retry_node(node)
builder.keyword_cmd(:retry, token(node.location))
end
# return
# ^^^^^^
#
# return 1
# ^^^^^^^^
def visit_return_node(node)
builder.keyword_cmd(
:return,
token(node.keyword_loc),
nil,
visit(node.arguments) || [],
nil
)
end
# self
# ^^^^
def visit_self_node(node)
builder.self(token(node.location))
end
# class << self; end
# ^^^^^^^^^^^^^^^^^^
def visit_singleton_class_node(node)
builder.def_sclass(
token(node.class_keyword_loc),
token(node.operator_loc),
visit(node.expression),
node.body&.accept(copy_compiler(forwarding: [])),
token(node.end_keyword_loc)
)
end
# __ENCODING__
# ^^^^^^^^^^^^
def visit_source_encoding_node(node)
builder.accessible(builder.__ENCODING__(token(node.location)))
end
# __FILE__
# ^^^^^^^^
def visit_source_file_node(node)
builder.accessible(builder.__FILE__(token(node.location)))
end
# __LINE__
# ^^^^^^^^
def visit_source_line_node(node)
builder.accessible(builder.__LINE__(token(node.location)))
end
# foo(*bar)
# ^^^^
#
# def foo((bar, *baz)); end
# ^^^^
#
# def foo(*); bar(*); end
# ^
def visit_splat_node(node)
if node.expression.nil? && forwarding.include?(:*)
builder.forwarded_restarg(token(node.operator_loc))
elsif in_destructure
builder.restarg(token(node.operator_loc), token(node.expression&.location))
elsif in_pattern
builder.match_rest(token(node.operator_loc), token(node.expression&.location))
else
builder.splat(token(node.operator_loc), visit(node.expression))
end
end
# A list of statements.
def visit_statements_node(node)
builder.compstmt(visit_all(node.body))
end
# "foo"
# ^^^^^
def visit_string_node(node)
if node.opening&.start_with?("<<")
children, closing = visit_heredoc(InterpolatedStringNode.new(node.opening_loc, [node.copy(opening_loc: nil, closing_loc: nil, location: node.content_loc)], node.closing_loc, node.location))
builder.string_compose(token(node.opening_loc), children, closing)
elsif node.opening == "?"
builder.character([node.unescaped, srange(node.location)])
else
builder.string_compose(
token(node.opening_loc),
[builder.string_internal([node.unescaped, srange(node.content_loc)])],
token(node.closing_loc)
)
end
end
# super(foo)
# ^^^^^^^^^^
def visit_super_node(node)
arguments = node.arguments&.arguments || []
block = node.block
if block.is_a?(BlockArgumentNode)
arguments = [*arguments, block]
block = nil
end
visit_block(
builder.keyword_cmd(
:super,
token(node.keyword_loc),
token(node.lparen_loc),
visit_all(arguments),
token(node.rparen_loc)
),
block
)
end
# :foo
# ^^^^
def visit_symbol_node(node)
if node.closing_loc.nil?
if node.opening_loc.nil?
builder.symbol_internal([node.unescaped, srange(node.location)])
else
builder.symbol([node.unescaped, srange(node.location)])
end
else
builder.symbol_compose(
token(node.opening_loc),
[builder.string_internal([node.unescaped, srange(node.value_loc)])],
token(node.closing_loc)
)
end
end
# true
# ^^^^
def visit_true_node(node)
builder.true(token(node.location))
end
# undef foo
# ^^^^^^^^^
def visit_undef_node(node)
builder.undef_method(token(node.keyword_loc), visit_all(node.names))
end
# unless foo; bar end
# ^^^^^^^^^^^^^^^^^^^
#
# bar unless foo
# ^^^^^^^^^^^^^^
def visit_unless_node(node)
if node.keyword_loc.start_offset == node.location.start_offset
builder.condition(
token(node.keyword_loc),
visit(node.predicate),
if node.then_keyword_loc
token(node.then_keyword_loc)
else
srange_find(node.predicate.location.end_offset, (node.statements&.location || node.consequent&.location || node.end_keyword_loc).start_offset, [";"])
end,
visit(node.consequent),
token(node.consequent&.else_keyword_loc),
visit(node.statements),
token(node.end_keyword_loc)
)
else
builder.condition_mod(
visit(node.consequent),
visit(node.statements),
token(node.keyword_loc),
visit(node.predicate)
)
end
end
# until foo; bar end
# ^^^^^^^^^^^^^^^^^
#
# bar until foo
# ^^^^^^^^^^^^^
def visit_until_node(node)
if node.location.start_offset == node.keyword_loc.start_offset
builder.loop(
:until,
token(node.keyword_loc),
visit(node.predicate),
srange_find(node.predicate.location.end_offset, (node.statements&.location || node.closing_loc).start_offset, [";", "do"]),
visit(node.statements),
token(node.closing_loc)
)
else
builder.loop_mod(
:until,
visit(node.statements),
token(node.keyword_loc),
visit(node.predicate)
)
end
end
# case foo; when bar; end
# ^^^^^^^^^^^^^
def visit_when_node(node)
builder.when(
token(node.keyword_loc),
visit_all(node.conditions),
srange_find(node.conditions.last.location.end_offset, node.statements&.location&.start_offset || (node.conditions.last.location.end_offset + 1), [";", "then"]),
visit(node.statements)
)
end
# while foo; bar end
# ^^^^^^^^^^^^^^^^^^
#
# bar while foo
# ^^^^^^^^^^^^^
def visit_while_node(node)
if node.location.start_offset == node.keyword_loc.start_offset
builder.loop(
:while,
token(node.keyword_loc),
visit(node.predicate),
srange_find(node.predicate.location.end_offset, (node.statements&.location || node.closing_loc).start_offset, [";", "do"]),
visit(node.statements),
token(node.closing_loc)
)
else
builder.loop_mod(
:while,
visit(node.statements),
token(node.keyword_loc),
visit(node.predicate)
)
end
end
# `foo`
# ^^^^^
def visit_x_string_node(node)
if node.opening&.start_with?("<<")
children, closing = visit_heredoc(InterpolatedXStringNode.new(node.opening_loc, [StringNode.new(0, nil, node.content_loc, nil, node.unescaped, node.content_loc)], node.closing_loc, node.location))
builder.xstring_compose(token(node.opening_loc), children, closing)
else
builder.xstring_compose(
token(node.opening_loc),
[builder.string_internal([node.unescaped, srange(node.content_loc)])],
token(node.closing_loc)
)
end
end
# yield
# ^^^^^
#
# yield 1
# ^^^^^^^
def visit_yield_node(node)
builder.keyword_cmd(
:yield,
token(node.keyword_loc),
token(node.lparen_loc),
visit(node.arguments) || [],
token(node.rparen_loc)
)
end
private
# Initialize a new compiler with the given option overrides, used to
# visit a subtree with the given options.
def copy_compiler(forwarding: self.forwarding, in_destructure: self.in_destructure, in_pattern: self.in_pattern)
Compiler.new(parser, offset_cache, forwarding: forwarding, in_destructure: in_destructure, in_pattern: in_pattern)
end
# When *, **, &, or ... are used as an argument in a method call, we
# check if they were allowed by the current context. To determine that
# we build this lookup table.
def find_forwarding(node)
return [] if node.nil?
forwarding = []
forwarding << :* if node.rest.is_a?(RestParameterNode) && node.rest.name.nil?
forwarding << :** if node.keyword_rest.is_a?(KeywordRestParameterNode) && node.keyword_rest.name.nil?
forwarding << :& if !node.block.nil? && node.block.name.nil?
forwarding |= [:&, :"..."] if node.keyword_rest.is_a?(ForwardingParameterNode)
forwarding
end
# Blocks can have a special set of parameters that automatically expand
# when given arrays if they have a single required parameter and no
# other parameters.
def procarg0?(parameters)
parameters &&
parameters.requireds.length == 1 &&
parameters.optionals.empty? &&
parameters.rest.nil? &&
parameters.posts.empty? &&
parameters.keywords.empty? &&
parameters.keyword_rest.nil? &&
parameters.block.nil?
end
# Locations in the parser gem AST are generated using this class. We
# store a reference to its constant to make it slightly faster to look
# up.
Range = ::Parser::Source::Range
# Constructs a new source range from the given start and end offsets.
def srange(location)
Range.new(source_buffer, offset_cache[location.start_offset], offset_cache[location.end_offset]) if location
end
# Constructs a new source range from the given start and end offsets.
def srange_offsets(start_offset, end_offset)
Range.new(source_buffer, offset_cache[start_offset], offset_cache[end_offset])
end
# Constructs a new source range by finding the given tokens between the
# given start offset and end offset. If the needle is not found, it
# returns nil.
def srange_find(start_offset, end_offset, tokens)
tokens.find do |token|
next unless (index = source_buffer.source.byteslice(start_offset...end_offset).index(token))
offset = start_offset + index
return [token, Range.new(source_buffer, offset_cache[offset], offset_cache[offset + token.length])]
end
end
# Transform a location into a token that the parser gem expects.
def token(location)
[location.slice, Range.new(source_buffer, offset_cache[location.start_offset], offset_cache[location.end_offset])] if location
end
# Visit a block node on a call.
def visit_block(call, block)
if block
parameters = block.parameters
builder.block(
call,
token(block.opening_loc),
if parameters.nil?
builder.args(nil, [], nil, false)
elsif parameters.is_a?(NumberedParametersNode)
visit(parameters)
else
builder.args(
token(parameters.opening_loc),
if procarg0?(parameters.parameters)
parameter = parameters.parameters.requireds.first
[builder.procarg0(visit(parameter))].concat(visit_all(parameters.locals))
else
visit(parameters)
end,
token(parameters.closing_loc),
false
)
end,
block.body&.accept(copy_compiler(forwarding: parameters.is_a?(NumberedParametersNode) ? [] : find_forwarding(parameters&.parameters))),
token(block.closing_loc)
)
else
call
end
end
# Visit a heredoc that can be either a string or an xstring.
def visit_heredoc(node)
children = []
node.parts.each do |part|
pushing =
if part.is_a?(StringNode) && part.unescaped.include?("\n")
unescaped = part.unescaped.lines(chomp: true)
escaped = part.content.lines(chomp: true)
escaped_lengths =
if node.opening.end_with?("'")
escaped.map { |line| line.bytesize + 1 }
else
escaped.chunk_while { |before, after| before.match?(/(?<!\\)\\$/) }.map { |line| line.join.bytesize + line.length }
end
start_offset = part.location.start_offset
end_offset = nil
unescaped.zip(escaped_lengths).map do |unescaped_line, escaped_length|
end_offset = start_offset + (escaped_length || 0)
inner_part = builder.string_internal(["#{unescaped_line}\n", srange_offsets(start_offset, end_offset)])
start_offset = end_offset
inner_part
end
else
[visit(part)]
end
pushing.each do |child|
if child.type == :str && child.children.last == ""
# nothing
elsif child.type == :str && children.last && children.last.type == :str && !children.last.children.first.end_with?("\n")
children.last.children.first << child.children.first
else
children << child
end
end
end
closing = node.closing
closing_t = [closing.chomp, srange_offsets(node.closing_loc.start_offset, node.closing_loc.end_offset - (closing[/\s+$/]&.length || 0))]
[children, closing_t]
end
# Visit a numeric node and account for the optional sign.
def visit_numeric(node, value)
if (slice = node.slice).match?(/^[+-]/)
builder.unary_num(
[slice[0].to_sym, srange_offsets(node.location.start_offset, node.location.start_offset + 1)],
value
)
else
value
end
end
# Within the given block, track that we're within a pattern.
def within_pattern
begin
parser.pattern_variables.push
yield copy_compiler(in_pattern: true)
ensure
parser.pattern_variables.pop
end
end
end
end
end
end