treesittertest.c

#include <assert.h>
#include <string.h>
#include <stdio.h>
#include <tree_sitter/api.h>
#include <tree_sitter/highlight.h>

TSLanguage *tree_sitter_c();

int main() {
  // Create a parser.
  TSParser *parser = ts_parser_new();

  // Set the parser's language (JSON in this case).
  ts_parser_set_language(parser, tree_sitter_c());

  // Build a syntax tree based on source code stored in a string.
  const char *source_code = "#include <assert.h>\n"
    "int main(int argc, char** argv) {\n"
    "  int a = 3 + argc;\n"
    "  printf(\"%d\\n\", a);\n"
    "}\n";
  TSTree *tree = ts_parser_parse_string(
    parser,
    NULL,
    source_code,
    strlen(source_code)
  );

  // Get the root node of the syntax tree.
  TSNode root_node = ts_tree_root_node(tree);

  char *string = ts_node_string(root_node);
  printf("# Syntax tree:\n%s\n\n", string);
  free(string);

  printf("# Source:\n%s\n", source_code);

  char highlights_query[4096] = {0};
  FILE* f = fopen("tree-sitter-c/queries/highlights.scm", "r");
  fread(highlights_query, sizeof(char), sizeof(highlights_query), f);
  fclose(f);

  uint32_t error_offset;
  TSQueryError error_type;
  const TSQuery* query = ts_query_new(
    tree_sitter_c(),
    highlights_query,
    strlen(highlights_query),
    &error_offset,
    &error_type
  );
  if (query == NULL) {
    printf("error at %d: %d\n", error_offset, error_type);
    return 1;
  }

  TSQueryCursor* cursor = ts_query_cursor_new();
  ts_query_cursor_exec(cursor, query, root_node);

  TSQueryMatch match;
  while (ts_query_cursor_next_match(cursor, &match)) {
    printf("[%3d] index=%d: ", match.id, match.pattern_index);
    for (int i = 0; i < match.capture_count; i++) {
      TSQueryCapture capture = match.captures[i];

      char* string = ts_node_string(capture.node);
      TSPoint start = ts_node_start_point(capture.node);
      TSPoint end = ts_node_end_point(capture.node);

      printf("[%2d:%-2d - %2d:%-2d] %s ", start.row, start.column, end.row, end.column, string);
      free(string);
    }
    puts("");
  }

  ts_tree_delete(tree);
  ts_parser_delete(parser);
  return 0;
}