SyntaxNode .toJSON() does not behave as expected

[maddrag0n]

SyntaxNode.toJSON() does not result in the JSON representable version of the SyntaxNode

Example

const parser = new TreeSitter();
parser.setLanguage(TreeSitterTypescript.tsx as Language);

const tree = parser.parse('import type { PropsWithChildren } from \'react\';\n\nexport function MyComponent({ children }: PropsWithChildren<{}>) {\n  return (\n    <div>{children}</div>\n  );\n}');

/*
this will not return a stringified JSON representation of the actual rootNode, but some parsed meta:

{
  "0": 62244512,
  "1": 24576,
  "2": 0,
  "3": 0,
  "4": 0,
  "5": 0,
  "tree": {
    "input": "import type { PropsWithChildren } from 'react';\n\nexport function MyComponent({ children }: PropsWithChildren<{}>) {\n  return (\n    <div>{children}</div>\n  );\n}",
    "language": { … }
  }
}

*/
JSON.stringify(tree.rootNode, undefined, '  ');

/* this returns a stringified JSON array of the same parsed meta

[
  {
    "0": 14798304,
    "1": 24576,
    "2": 0,
    "3": 0,
    "4": 0,
    "5": 0,
    "tree": {
      "input": "import type { PropsWithChildren } from 'react';\n\nexport function MyComponent({ children }: PropsWithChildren<{}>) {\n  return (\n    <div>{children}</div>\n  );\n}",
      "language": { … }
    }
  },
  {
    "0": 14734976,
    "1": 24576,
    "2": 98,
    "3": 2,
    "4": 0,
    "5": 0,
    "tree": {
      "input": "import type { PropsWithChildren } from 'react';\n\nexport function MyComponent({ children }: PropsWithChildren<{}>) {\n  return (\n    <div>{children}</div>\n  );\n}",
      "language": { … }
    }
  }
]

*/
JSON.stringify(tree.rootNode.children, undefined, '  ');