refactor: move list identifier to scanner

Close rescript-lang#189

Author: aspeddro

grammar.js

@@ -10,6 +10,7 @@ module.exports = grammar({
     $._template_chars,
     $._lparen,
     $._rparen,
+    $._list_constructor
   ],
 
   extras: $ => [
@@ -637,7 +638,8 @@ module.exports = grammar({
     ),
 
     list: $ => seq(
-      'list{',
+      $._list_constructor,
+      '{',
       optional(commaSep1t($._list_element)),
       '}'
     ),
@@ -939,7 +941,8 @@ module.exports = grammar({
     ),
 
     list_pattern: $ => seq(
-      'list{',
+      $._list_constructor,
+      '{',
       optional(commaSep1t($._collection_element_pattern)),
       '}',
     ),

queries/highlights.scm

@@ -10,16 +10,10 @@
 [
   (type_identifier)
   (unit_type)
+  (list)
+  (list_pattern)
 ] @type
 
-
-(list "list{" @type)
-(list_pattern "list{" @type)
-
-; To ensure that the closing curly bracket is the same color (scope) as the opening curly bracket
-(list "}" @type (#set! "priority" 105))
-(list_pattern "}" @type (#set! "priority" 105))
-
 [
   (variant_identifier)
   (polyvar_identifier)

src/scanner.c

@@ -11,6 +11,7 @@ enum TokenType {
   TEMPLATE_CHARS,
   L_PAREN,
   R_PAREN,
+  LIST_CONSTRUCTOR
 };
 
 typedef struct ScannerState {
@@ -44,6 +45,7 @@ void tree_sitter_rescript_external_scanner_deserialize(void* state, const char *
 }
 
 static void advance(TSLexer *lexer) { lexer->advance(lexer, false); }
+static void skip(TSLexer *lexer) { lexer->advance(lexer, true); }
 
 static bool is_inline_whitespace(int32_t c) {
   return c == ' ' || c == '\t';
@@ -138,7 +140,7 @@ bool tree_sitter_rescript_external_scanner_scan(
   const in_string = state->in_quotes || state->in_backticks;
 
   while (is_inline_whitespace(lexer->lookahead) && !in_string) {
-    advance(lexer);
+    skip(lexer);
   }
 
   if (valid_symbols[TEMPLATE_CHARS]) {
@@ -285,6 +287,26 @@ bool tree_sitter_rescript_external_scanner_scan(
     return true;
   }
 
+  if (valid_symbols[LIST_CONSTRUCTOR]) {
+    lexer->result_symbol = LIST_CONSTRUCTOR;
+    if (lexer->lookahead == 'l') {
+      advance(lexer);
+      if (lexer->lookahead == 'i') {
+        advance(lexer);
+        if (lexer->lookahead == 's') {
+          advance(lexer);
+          if (lexer->lookahead == 't') {
+            advance(lexer);
+            if (lexer->lookahead == '{') {
+              lexer->mark_end(lexer);
+              return true;
+            }
+          }
+        }
+      }
+    }
+  }
+
   lexer->advance(lexer, iswspace(lexer->lookahead));
   return false;
 }

test/highlight/expressions.res

@@ -52,6 +52,6 @@ try {
 
 
 let c = list{a, ...list{b}}
-//          ^ type
+//        ^ type
 //           ^ variable
 //                      ^ variable