Working on more parity

Author: isometriks

lib/twig/expression_parser/infix/assignment.rb

@@ -0,0 +1,48 @@
+# frozen_string_literal: true
+
+module Twig
+  module ExpressionParser
+    module Infix
+      class Assignment < InfixExpressionParser
+        def parse(parser, left, token)
+          right = parser.parse_expression(precedence)
+
+          case left
+          when Node::Expression::Array
+            return Node::Expression::Binary::SequenceDestructuringSetBinary.new(left, right, token.lineno)
+          when Node::Expression::Hash
+            return Node::Expression::Binary::ObjectDestructuringSetBinary.new(left, right, token.lineno)
+          when Node::Expression::Variable::Context
+            return Node::Expression::Binary::SetBinary.new(left, right, token.lineno)
+          end
+
+          raise Error::Syntax.new(
+            "Cannot assign to \"#{left.class}\", only variables can be assigned.",
+            token.lineno,
+            parser.stream.source
+          )
+        end
+
+        def name
+          '='
+        end
+
+        def description
+          'Assignment operator'
+        end
+
+        def precedence
+          0
+        end
+
+        def associativity
+          RIGHT
+        end
+
+        def aliases
+          []
+        end
+      end
+    end
+  end
+end

lib/twig/expression_parser/infix/dot.rb

@@ -24,7 +24,7 @@ def parse(parser, left, _token)
               attribute = Node::Expression::Constant.new(token.value, token.lineno)
             else
               raise Error::Syntax.new(
-                "Expected name or number, got value \"#{token.value}\" of type #{token.type}.",
+                "Expected name or number, got value \"#{token.value}\" of type \"#{token.to_english}\".",
                 token.lineno,
                 stream.source
               )

lib/twig/expression_parser/infix/parses_arguments.rb

@@ -50,8 +50,11 @@ def parse_named_arguments(parser, parse_open_parenthesis: true)
           end
 
           name = nil
-          if (token = stream.next_if(Token::OPERATOR_TYPE, '=')) ||
-             (token = stream.next_if(Token::PUNCTUATION_TYPE, ':'))
+          if value.is_a?(Node::Expression::Binary::SetBinary)
+            name = value.nodes[:left].attributes[:name]
+            value = value.nodes[:right]
+          elsif (token = stream.next_if(Token::OPERATOR_TYPE, '=')) ||
+                (token = stream.next_if(Token::PUNCTUATION_TYPE, ':'))
             # Allow quoted kwargs - form_with("data-turbo-stream": true)
             if value.is_a?(Node::Expression::Constant) && value.attributes[:value].is_a?(String)
               name = value.attributes[:value]

lib/twig/expression_parser/prefix/literal.rb

@@ -77,14 +77,6 @@ def parse(parser, token)
               return Node::Expression::Variable::Context.new(token.value, token.lineno)
             end
 
-            if token.value == '=' && %w[== !=].include?(parser.stream.look(-1).value)
-              raise Error::Syntax.new(
-                "Unexpected operator of value \"#{token.value}\". Did you try to use \"===\" or \"!==\" for " \
-                'strict comparison? Use "is same as(value)" instead.',
-                token.lineno,
-                parser.stream.source
-              )
-            end
           end
 
           raise Error::Syntax.new(
@@ -155,7 +147,9 @@ def parse_sequence_expression(parser)
 
             first = false
 
-            if stream.next_if(Token::OPERATOR_TYPE, '...')
+            if stream.test(Token::PUNCTUATION_TYPE, ',') || stream.test(Token::PUNCTUATION_TYPE, ']')
+              node.add_element(Node::Expression::EmptySlot.new(stream.current.lineno))
+            elsif stream.next_if(Token::OPERATOR_TYPE, '...')
               expr = parser.parse_expression
               node.add_element(Node::Expression::Unary::ArraySpread.new(expr, expr.lineno))
             else

lib/twig/expression_parser/prefix/unary.rb

@@ -6,18 +6,19 @@ module Prefix
       class Unary < PrefixExpressionParser
         attr_reader :aliases, :precedence, :name
 
-        def initialize(node_class, name, precedence, description: nil, aliases: [])
+        def initialize(node_class, name, precedence, description: nil, aliases: [], operand_precedence: nil)
           super()
 
           @node_class = node_class
           @name = name
           @precedence = precedence
+          @operand_precedence = operand_precedence
           @description = description
           @aliases = aliases
         end
 
         def parse(parser, token)
-          @node_class.new(parser.parse_expression(precedence), token.lineno)
+          @node_class.new(parser.parse_expression(@operand_precedence || precedence), token.lineno)
         end
 
         def description

lib/twig/extension/core.rb

@@ -25,7 +25,7 @@ def expression_parsers
         [
           # Unary operators
           unary.new(Node::Expression::Unary::Not, 'not', 70),
-          unary.new(Node::Expression::Unary::Spread, '...', 512, description: 'Spread Operator'),
+          unary.new(Node::Expression::Unary::Spread, '...', 512, description: 'Spread Operator', operand_precedence: 0),
           unary.new(Node::Expression::Unary::Neg, '-', 500),
           unary.new(Node::Expression::Unary::Pos, '+', 500),
 
@@ -46,6 +46,8 @@ def expression_parsers
           binary.new(Node::Expression::Binary::BitwiseAnd, 'b-and', 16),
           binary.new(Node::Expression::Binary::Equal, '==', 20),
           binary.new(Node::Expression::Binary::NotEqual, '!=', 20),
+          binary.new(Node::Expression::Binary::SameAs, '===', 20),
+          binary.new(Node::Expression::Binary::NotSameAs, '!==', 20),
           binary.new(Node::Expression::Binary::Spaceship, '<=>', 20),
           binary.new(Node::Expression::Binary::Less, '<', 20),
           binary.new(Node::Expression::Binary::Greater, '>', 20),
@@ -87,6 +89,9 @@ def expression_parsers
           # Arrow function
           ExpressionParser::Infix::Arrow.new,
 
+          # Assignment operator
+          ExpressionParser::Infix::Assignment.new,
+
           # All literals
           ExpressionParser::Prefix::Literal.new,
         ]

lib/twig/lexer.rb

@@ -457,7 +457,7 @@ def lex_raw_data_regex
     def operator_regex
       return @operator_regex if defined?(@operator_regex)
 
-      expression_parsers = ['=']
+      expression_parsers = []
 
       environment.expression_parsers.each do |expression_parser|
         expression_parsers.concat([expression_parser.name], expression_parser.aliases)

lib/twig/node/expression/array.rb

@@ -24,6 +24,14 @@ def compile(compiler)
             return compiler.repr(true)
           end
 
+          # Empty expressions are only valid in destructuring contexts
+          values.each do |value|
+            if value.is_a?(Expression::EmptySlot)
+              raise Error::Syntax.new('Empty array elements are only allowed in destructuring assignments.',
+                value.lineno)
+            end
+          end
+
           compiler.
             raw('[').
             indent

lib/twig/node/expression/binary/base.rb

@@ -49,6 +49,8 @@ def operator(compiler)
           Div: '/',
           Mod: '%',
           Power: '**',
+          SameAs: '==',
+          NotSameAs: '!=',
         }.freeze
 
         # Lots of simple operator classes can just be generated dynamically

lib/twig/node/expression/binary/object_destructuring_set_binary.rb

@@ -0,0 +1,61 @@
+# frozen_string_literal: true
+
+module Twig
+  module Node
+    module Expression
+      module Binary
+        class ObjectDestructuringSetBinary < Binary::Base
+          def initialize(left, right, lineno)
+            @mappings = []
+
+            left.key_value_pairs.each do |key, value|
+              unless value.is_a?(Variable::Context)
+                raise Error::Syntax.new(
+                  "Cannot assign to \"#{value.class}\", only variables can be assigned in " \
+                  'object/mapping destructuring.',
+                  lineno
+                )
+              end
+
+              @mappings << {
+                property: key.attributes[:value],
+                variable: value.attributes[:name],
+              }
+            end
+
+            super
+          end
+
+          def compile(compiler)
+            compiler.add_debug_info(self)
+
+            @mappings.each_with_index do |mapping, i|
+              compiler.raw(', ') if i.positive?
+              compiler.raw('context[').string(mapping[:variable]).raw(']')
+            end
+
+            compiler.raw(' = ')
+
+            @mappings.each_with_index do |mapping, i|
+              compiler.raw(', ') if i.positive?
+              compiler.
+                raw('::Twig::Extension::Core.get_attribute(env, source_context, ').
+                subcompile(nodes[:right]).
+                raw(', ').
+                repr(mapping[:property]).
+                raw(', ').
+                repr(Template::ANY_CALL).
+                raw(', lineno: ').
+                repr(nodes[:right].lineno).
+                raw(')')
+            end
+          end
+
+          def operator(compiler)
+            compiler.raw('=')
+          end
+        end
+      end
+    end
+  end
+end