New Patterns (#155)

* Adds `pattern` construct in place of `formal_parameter`

* Adds generated source files.

* Makes patterns a supertype, also removes some unneeded comments.

* Fixes bugs due to new patterns

* Simplifies locals.scm query

* Make patterns visible.

* Allow primary_expression to be targeted as a supertype

* Removes extraneous comments

Co-authored-by: Max Brunsfeld <[email protected]>

Author: BekaValentine

grammar.js

@@ -41,17 +41,15 @@ module.exports = grammar({
     $._statement,
     $._declaration,
     $._expression,
-    $._destructuring_pattern,
+    $.primary_expression,
+    $.pattern,
   ],
 
   inline: $ => [
     $._call_signature,
-    $._primary_expression,
     $._statement,
     $._expressions,
     $._semicolon,
-    $._formal_parameter,
-    $._destructuring_pattern,
     $._reserved_identifier,
     $._jsx_attribute,
     $._jsx_element_name,
@@ -64,16 +62,22 @@ module.exports = grammar({
   ],
 
   conflicts: $ => [
-    [$._expression, $._property_name],
-    [$._expression, $._property_name, $.arrow_function],
-    [$._expression, $.arrow_function],
-    [$._expression, $.method_definition],
-    [$._expression, $.formal_parameters],
-    [$._expression, $.rest_parameter],
+    [$.primary_expression, $._property_name],
+    [$.primary_expression, $._property_name, $.arrow_function],
+    [$.primary_expression, $.arrow_function],
+    [$.primary_expression, $.method_definition],
+    [$.primary_expression, $.rest_parameter],
+    [$.primary_expression, $.pattern],
+    [$.primary_expression, $.assignment_expression, ],
+    [$.primary_expression, $._for_header],
+    [$.object, $.object_pattern],
+    [$.array, $.array_pattern],
+    [$.assignment_expression, $.pattern],
+    [$.assignment_expression, $.rest_parameter],
+    [$.assignment_expression, $.object_assignment_pattern],
+    [$.assignment_expression, $.assignment_pattern],
     [$.labeled_statement, $._property_name],
-    [$.assignment_pattern, $.assignment_expression],
     [$.computed_property_name, $.array],
-    [$._for_header, $._expression],
   ],
 
   word: $ => $.identifier,
@@ -401,7 +405,7 @@ module.exports = grammar({
     ),
 
     _expression: $ => choice(
-      $._primary_expression,
+      $.primary_expression,
       $._jsx_element,
       $.jsx_fragment,
       $.assignment_expression,
@@ -415,7 +419,7 @@ module.exports = grammar({
       $.yield_expression,
     ),
 
-    _primary_expression: $ => choice(
+    primary_expression: $ => choice(
       $.this,
       $.super,
       $.identifier,
@@ -455,7 +459,6 @@ module.exports = grammar({
         $.pair,
         $.spread_element,
         $.method_definition,
-        $.assignment_pattern,
         alias(
           choice($.identifier, $._reserved_identifier),
           $.shorthand_property_identifier
@@ -464,9 +467,29 @@ module.exports = grammar({
       '}'
     )),
 
+    object_pattern: $ => prec(PREC.OBJECT, seq(
+      '{',
+      commaSep(optional(choice(
+        $.pair_pattern,
+        $.rest_parameter,
+        $.object_assignment_pattern,
+        alias(
+          choice($.identifier, $._reserved_identifier),
+          $.shorthand_property_identifier_pattern
+        )
+      ))),
+      '}'
+    )),
+
     assignment_pattern: $ => seq(
+      field('left', $.pattern),
+      '=',
+      field('right', $._expression)
+    ),
+
+    object_assignment_pattern: $ => seq(
       field('left', choice(
-        alias(choice($._reserved_identifier, $.identifier), $.shorthand_property_identifier),
+        alias(choice($._reserved_identifier, $.identifier), $.shorthand_property_identifier_pattern),
         $._destructuring_pattern
       )),
       '=',
@@ -482,6 +505,14 @@ module.exports = grammar({
       ']'
     ),
 
+    array_pattern: $ => seq(
+      '[',
+      commaSep(optional(choice(
+        $.pattern
+      ))),
+      ']'
+    ),
+
     _jsx_element: $ => choice($.jsx_element, $.jsx_self_closing_element),
 
     jsx_element: $ => seq(
@@ -655,15 +686,15 @@ module.exports = grammar({
         field('arguments', choice($.arguments, $.template_string))
       )),
       prec(PREC.MEMBER, seq(
-        field('function', $._primary_expression),
+        field('function', $.primary_expression),
         '?.',
         field('arguments', $.arguments)
       ))
     ),
 
     new_expression: $ => prec.right(PREC.NEW, seq(
       'new',
-      field('constructor', $._primary_expression),
+      field('constructor', $.primary_expression),
       field('arguments', optional(prec.dynamic(1, $.arguments)))
     )),
 
@@ -673,13 +704,13 @@ module.exports = grammar({
     ),
 
     member_expression: $ => prec(PREC.MEMBER, seq(
-      field('object', choice($._expression, $._primary_expression)),
+      field('object', choice($._expression, $.primary_expression)),
       choice('.', '?.'),
       field('property', alias($.identifier, $.property_identifier))
     )),
 
     subscript_expression: $ => prec.right(PREC.MEMBER, seq(
-      field('object', choice($._expression, $._primary_expression)),
+      field('object', choice($._expression, $.primary_expression)),
       optional('?.'),
       '[', field('index', $._expressions), ']'
     )),
@@ -719,8 +750,8 @@ module.exports = grammar({
     ),
 
     _destructuring_pattern: $ => choice(
-      alias($.object, $.object_pattern),
-      alias($.array, $.array_pattern)
+      $.object_pattern,
+      $.array_pattern
     ),
 
     spread_element: $ => seq('...', $._expression),
@@ -997,13 +1028,13 @@ module.exports = grammar({
     formal_parameters: $ => seq(
       '(',
       optional(seq(
-        commaSep1($._formal_parameter),
+        commaSep1($.pattern),
         optional(',')
       )),
       ')'
     ),
 
-    _formal_parameter: $ => choice(
+    pattern: $ => choice(
       $.identifier,
       alias($._reserved_identifier, $.identifier),
       $._destructuring_pattern,
@@ -1035,6 +1066,12 @@ module.exports = grammar({
       field('value', $._expression)
     ),
 
+    pair_pattern: $ => seq(
+      field('key', $._property_name),
+      ':',
+      field('value', $.pattern)
+    ),
+
     _property_name: $ => choice(
       alias(choice(
         $.identifier,

queries/highlights.scm

@@ -1,11 +1,13 @@
 ; Special identifiers
 ;--------------------
 
-((identifier) @constant
+([
+    (identifier)
+    (shorthand_property_identifier)
+    (shorthand_property_identifier_pattern)
+ ] @constant
  (#match? @constant "^[A-Z_][A-Z\\d_]+$"))
 
-((shorthand_property_identifier) @constant
- (#match? @constant "^[A-Z_][A-Z\\d_]+$"))
 
 ((identifier) @constructor
  (#match? @constructor "^[A-Z]"))
@@ -65,8 +67,8 @@
       (identifier) @variable.parameter)
     (object_pattern
       [
-        (pair value: (identifier) @variable.parameter)
-        (shorthand_property_identifier) @variable.parameter
+        (pair_pattern value: (identifier) @variable.parameter)
+        (shorthand_property_identifier_pattern) @variable.parameter
       ])
   ]
 )

queries/locals.scm

@@ -12,17 +12,7 @@
 ; Definitions
 ;------------
 
-(formal_parameters
-  [
-    (identifier) @local.definition
-    (array_pattern
-      (identifier) @local.definition)
-    (object_pattern
-      [
-        (pair value: (identifier) @local.definition)
-        (shorthand_property_identifier) @local.definition
-      ])
-  ])
+(pattern/identifier)@local.definition
 
 (variable_declarator
   name: (identifier) @local.definition)