Add external parser for parsing bracket_argument and also adjust the

test cases accordingly

corpus/bracket_argument.txt

@@ -22,7 +22,7 @@ message([[an argument]])
 (source_file
  (message_command
   (message)
-  (argument (bracket_argument (bracket_content)))
+  (argument (bracket_argument))
  )
  )
 
@@ -36,8 +36,8 @@ message([[first argument]] [[second argument]])
 (source_file
  (message_command
   (message)
-  (argument (bracket_argument (bracket_content)))
+  (argument (bracket_argument))
-  (argument (bracket_argument (bracket_content)))
+  (argument (bracket_argument))
  )
  )
 
@@ -54,8 +54,8 @@ message(
 (source_file
  (message_command
   (message)
-  (argument (bracket_argument (bracket_content)))
+  (argument (bracket_argument))
-  (argument (bracket_argument (bracket_content)))
+  (argument (bracket_argument))
  )
  )
 
@@ -71,7 +71,23 @@ with line break
 (source_file
  (message_command
   (message)
-  (argument (bracket_argument (bracket_content)))
+  (argument (bracket_argument))
+ )
+ )
+
+=====================================================================================
+Bracket argument with embedded brackets and equal signs line break [bracket_argument]
+=====================================================================================
+
+message([===[an argument
+with line break ]==]
+]===])
+
+---
+(source_file
+ (message_command
+  (message)
+  (argument (bracket_argument))
  )
  )
 

corpus/message.txt

@@ -41,3 +41,18 @@ message(
   (message)
  )
  )
+
+==================================================
+Message with STATUS and bracket argument [message]
+==================================================
+
+message(STATUS [=[Some argument ]==] ]=] )
+
+---
+
+(source_file
+ (message_command
+  (message)
+  (argument (bracket_argument))
+ )
+ )

grammar.js

@@ -79,6 +79,8 @@ message_args = [
 module.exports = grammar({
   name: "cmake",
 
+  externals: ($) => [$.bracket_argument],
+
   rules: {
     source_file: ($) => repeat($._command_invocation),
 
@@ -95,11 +97,6 @@ module.exports = grammar({
 
     argument: ($) => choice($.bracket_argument, $.quoted_argument, $.unquoted_argument),
 
-    bracket_argument: ($) => seq($._bracket_open, optional($.bracket_content), $._bracket_close),
-    _bracket_open: (_) => seq("[", repeat("="), "["),
-    bracket_content: (_) => repeat1(/[^\]]/),
-    _bracket_close: (_) => seq("]", repeat("="), "]"),
-
     quoted_argument: ($) => seq('"', optional($.quoted_element), '"'),
     quoted_element: ($) => repeat1(choice($.variable_ref, /[^\\"]/, $.escape_sequence, seq("\\", newline()))),
 

src/grammar.json

@@ -163,78 +163,6 @@
         }
       ]
     },
-    "bracket_argument": {
-      "type": "SEQ",
-      "members": [
-        {
-          "type": "SYMBOL",
-          "name": "_bracket_open"
-        },
-        {
-          "type": "CHOICE",
-          "members": [
-            {
-              "type": "SYMBOL",
-              "name": "bracket_content"
-            },
-            {
-              "type": "BLANK"
-            }
-          ]
-        },
-        {
-          "type": "SYMBOL",
-          "name": "_bracket_close"
-        }
-      ]
-    },
-    "_bracket_open": {
-      "type": "SEQ",
-      "members": [
-        {
-          "type": "STRING",
-          "value": "["
-        },
-        {
-          "type": "REPEAT",
-          "content": {
-            "type": "STRING",
-            "value": "="
-          }
-        },
-        {
-          "type": "STRING",
-          "value": "["
-        }
-      ]
-    },
-    "bracket_content": {
-      "type": "REPEAT1",
-      "content": {
-        "type": "PATTERN",
-        "value": "[^\\]]"
-      }
-    },
-    "_bracket_close": {
-      "type": "SEQ",
-      "members": [
-        {
-          "type": "STRING",
-          "value": "]"
-        },
-        {
-          "type": "REPEAT",
-          "content": {
-            "type": "STRING",
-            "value": "="
-          }
-        },
-        {
-          "type": "STRING",
-          "value": "]"
-        }
-      ]
-    },
     "quoted_argument": {
       "type": "SEQ",
       "members": [
@@ -3337,7 +3265,12 @@
   ],
   "conflicts": [],
   "precedences": [],
-  "externals": [],
+  "externals": [
+    {
+      "type": "SYMBOL",
+      "name": "bracket_argument"
+    }
+  ],
   "inline": [],
   "supertypes": []
 }

src/node-types.json

@@ -22,26 +22,6 @@
       ]
     }
   },
-  {
-    "type": "bracket_argument",
-    "named": true,
-    "fields": {},
-    "children": {
-      "multiple": false,
-      "required": false,
-      "types": [
-        {
-          "type": "bracket_content",
-          "named": true
-        }
-      ]
-    }
-  },
-  {
-    "type": "bracket_content",
-    "named": true,
-    "fields": {}
-  },
   {
     "type": "cache_var",
     "named": true,
@@ -763,10 +743,6 @@
     "type": "1",
     "named": false
   },
-  {
-    "type": "=",
-    "named": false
-  },
   {
     "type": "AND",
     "named": false
@@ -1007,10 +983,6 @@
     "type": "ZIP_LISTS",
     "named": false
   },
-  {
-    "type": "[",
-    "named": false
-  },
   {
     "type": "\\",
     "named": false
@@ -1028,8 +1000,8 @@
     "named": false
   },
   {
-    "type": "]",
+    "type": "bracket_argument",
-    "named": false
+    "named": true
   },
   {
     "type": "else",

src/scanner.cc

@@ -0,0 +1,69 @@
+#include <cwctype>
+#include <iostream>
+#include <tree_sitter/parser.h>
+
+namespace {
+enum TokenType { BRACKET_ARGUMENT };
+void skip(TSLexer *lexer) { lexer->advance(lexer, true); }
+void advance(TSLexer *lexer) { lexer->advance(lexer, false); }
+bool scan(void *payload, TSLexer *lexer, const bool *valid_symbols) {
+  using std::iswspace;
+
+  if (!valid_symbols[BRACKET_ARGUMENT])
+    return false;
+
+  while (iswspace(lexer->lookahead))
+    skip(lexer);
+
+  if (lexer->lookahead != '[')
+    return false;
+
+  advance(lexer);
+
+  int open_level = 0;
+  while (lexer->lookahead == '=') {
+    ++open_level;
+    advance(lexer);
+  }
+
+  if (lexer->lookahead != '[')
+    return false;
+
+  while (lexer->lookahead != '\0') {
+    advance(lexer);
+    if (lexer->lookahead == ']') {
+      advance(lexer);
+
+      int close_level = 0;
+      while (lexer->lookahead == '=') {
+        ++close_level;
+        advance(lexer);
+      }
+
+      if (lexer->lookahead == ']' && close_level == open_level) {
+        advance(lexer);
+        lexer->result_symbol = BRACKET_ARGUMENT;
+        return true;
+      }
+    }
+  }
+
+  return false;
+}
+
+} // namespace
+extern "C" {
+void *tree_sitter_cmake_external_scanner_create() { return nullptr; }
+void tree_sitter_cmake_external_scanner_destroy(void *payload) {}
+unsigned tree_sitter_cmake_external_scanner_serialize(void *payload,
+                                                      char *buffer) {
+  return 0;
+}
+void tree_sitter_cmake_external_scanner_deserialize(void *payload,
+                                                    const char *buffer,
+                                                    unsigned length) {}
+bool tree_sitter_cmake_external_scanner_scan(void *payload, TSLexer *lexer,
+                                             const bool *valid_symbols) {
+  return scan(payload, lexer, valid_symbols);
+}
+}