diff options
Diffstat (limited to 'Userland/Libraries/LibJS/Parser.cpp')
| -rw-r--r-- | Userland/Libraries/LibJS/Parser.cpp | 162 |
1 files changed, 81 insertions, 81 deletions
diff --git a/Userland/Libraries/LibJS/Parser.cpp b/Userland/Libraries/LibJS/Parser.cpp index 48d286c102..36a23e12d6 100644 --- a/Userland/Libraries/LibJS/Parser.cpp +++ b/Userland/Libraries/LibJS/Parser.cpp @@ -1248,6 +1248,15 @@ NonnullRefPtr<AssignmentExpression> Parser::parse_assignment_expression(Assignme return create_ast_node<AssignmentExpression>({ m_parser_state.m_current_token.filename(), rule_start.position(), position() }, assignment_op, move(lhs), move(rhs)); } +NonnullRefPtr<Identifier> Parser::parse_identifier() +{ + auto identifier_start = position(); + auto token = consume(TokenType::Identifier); + return create_ast_node<Identifier>( + { m_parser_state.m_current_token.filename(), identifier_start, position() }, + token.value()); +} + NonnullRefPtr<CallExpression> Parser::parse_call_expression(NonnullRefPtr<Expression> lhs) { auto rule_start = push_start(); @@ -1522,36 +1531,28 @@ RefPtr<BindingPattern> Parser::parse_binding_pattern() { auto rule_start = push_start(); - auto pattern_ptr = adopt_ref(*new BindingPattern); - auto& pattern = *pattern_ptr; TokenType closing_token; - auto allow_named_property = false; - auto elide_extra_commas = false; - auto allow_nested_pattern = false; + bool is_object = true; if (match(TokenType::BracketOpen)) { consume(); - pattern.kind = BindingPattern::Kind::Array; closing_token = TokenType::BracketClose; - elide_extra_commas = true; - allow_nested_pattern = true; + is_object = false; } else if (match(TokenType::CurlyOpen)) { consume(); - pattern.kind = BindingPattern::Kind::Object; closing_token = TokenType::CurlyClose; - allow_named_property = true; } else { return {}; } + Vector<BindingPattern::BindingEntry> entries; + while (!match(closing_token)) { - if (elide_extra_commas && match(TokenType::Comma)) + if (!is_object && match(TokenType::Comma)) { consume(); - - ScopeGuard consume_commas { [&] { - if (match(TokenType::Comma)) - consume(); - } }; + entries.append(BindingPattern::BindingEntry {}); + continue; + } auto is_rest = false; @@ -1560,89 +1561,88 @@ RefPtr<BindingPattern> Parser::parse_binding_pattern() is_rest = true; } - if (match(TokenType::Identifier)) { - auto identifier_start = position(); - auto token = consume(TokenType::Identifier); - auto name = create_ast_node<Identifier>( - { m_parser_state.m_current_token.filename(), identifier_start, position() }, - token.value()); + decltype(BindingPattern::BindingEntry::name) name = Empty {}; + decltype(BindingPattern::BindingEntry::alias) alias = Empty {}; + RefPtr<Expression> initializer = {}; - if (!is_rest && allow_named_property && match(TokenType::Colon)) { + if (is_object) { + if (match(TokenType::Identifier)) { + name = parse_identifier(); + } else if (match(TokenType::BracketOpen)) { consume(); - if (!match(TokenType::Identifier)) { - syntax_error("Expected a binding pattern as the value of a named element in destructuring object"); - break; - } else { - auto identifier_start = position(); - auto token = consume(TokenType::Identifier); - auto alias_name = create_ast_node<Identifier>( - { m_parser_state.m_current_token.filename(), identifier_start, position() }, - token.value()); - pattern.properties.append(BindingPattern::BindingProperty { - .name = move(name), - .alias = move(alias_name), - .pattern = nullptr, - .initializer = nullptr, - .is_rest = false, - }); - } - continue; + name = parse_expression(0); + consume(TokenType::BracketOpen); + } else { + syntax_error("Expected identifier or computed property name"); + return {}; } - RefPtr<Expression> initializer; - if (match(TokenType::Equals)) { + if (!is_rest && match(TokenType::Colon)) { consume(); - initializer = parse_expression(2); + if (match(TokenType::CurlyOpen) || match(TokenType::BracketOpen)) { + auto binding_pattern = parse_binding_pattern(); + if (!binding_pattern) + return {}; + alias = binding_pattern.release_nonnull(); + } else if (match_identifier_name()) { + alias = parse_identifier(); + } else { + syntax_error("Expected identifier or binding pattern"); + return {}; + } + } + } else { + if (match(TokenType::Identifier)) { + // BindingElement must always have an Empty name field + alias = parse_identifier(); + } else if (match(TokenType::BracketOpen) || match(TokenType::CurlyOpen)) { + auto pattern = parse_binding_pattern(); + if (!pattern) { + syntax_error("Expected binding pattern"); + return {}; + } + alias = pattern.release_nonnull(); + } else { + syntax_error("Expected identifier or binding pattern"); + return {}; } - pattern.properties.append(BindingPattern::BindingProperty { - .name = move(name), - .alias = nullptr, - .pattern = nullptr, - .initializer = move(initializer), - .is_rest = is_rest, - }); - if (is_rest) - break; - continue; } - if (allow_nested_pattern) { - auto binding_pattern = parse_binding_pattern(); - if (!binding_pattern) { - if (is_rest) - syntax_error("Expected a binding pattern after ... in destructuring list"); - else - syntax_error("Expected a binding pattern or identifier in destructuring list"); - break; - } else { - RefPtr<Expression> initializer; - if (match(TokenType::Equals)) { - consume(); - initializer = parse_expression(2); - } - pattern.properties.append(BindingPattern::BindingProperty { - .name = nullptr, - .alias = nullptr, - .pattern = move(binding_pattern), - .initializer = move(initializer), - .is_rest = is_rest, - }); - if (is_rest) - break; - continue; + if (match(TokenType::Equals)) { + if (is_rest) { + syntax_error("Unexpected initializer after rest element"); + return {}; } - continue; + consume(); + + initializer = parse_expression(2); + if (!initializer) { + syntax_error("Expected initialization expression"); + return {}; + } } - break; + entries.append(BindingPattern::BindingEntry { move(name), move(alias), move(initializer), is_rest }); + + if (match(TokenType::Comma)) { + if (is_rest) { + syntax_error("Rest element may not be followed by a comma"); + return {}; + } + consume(); + } } - while (elide_extra_commas && match(TokenType::Comma)) + while (!is_object && match(TokenType::Comma)) consume(); consume(closing_token); + auto kind = is_object ? BindingPattern::Kind::Object : BindingPattern::Kind::Array; + auto pattern = adopt_ref(*new BindingPattern); + pattern->entries = move(entries); + pattern->kind = kind; return pattern; } |