Basic parsing Flow with Babel not working - parsing

Question

I cannot seem to be able to parse Flow using Babel, its not recognising types or "declare" and is coming up with errors on them :-
const fs = require("fs");
const babel = require("#babel/core");
const parser = require('#babel/parser');
const generate = require('#babel/generator').default;
if (process.argv.length == 3) {
const filename = process.argv[2];
const sourceCode = fs.readFileSync(filename).toString();
console.log("sourceCode = ", sourceCode);
var options = {
"sourceType": "module", // parse in strict mode and allow module declarations
"presets": ["#babel/preset-flow"]
};
const parsedAst = parser.parse(sourceCode, options);
console.log("parsedAst = ", parsedAst)
const { codeOutput, map, ast } = babel.transformFromAstSync(parsedAst, sourceCode, { ast: true } );
console.log("ast = ", JSON.stringify(ast, 2, 2))
const output = generate(ast, { /* options */ }, sourceCode);
console.log("codeOutput = ", codeOutput);
console.log("output = ", output);
};
given the following code :-
// #flow strict
const MAX_SUGGESTIONS = 5;
/**
* Given [ A, B, C ] return ' Did you mean A, B, or C?'.
*/
declare function didYouMean(suggestions: $ReadOnlyArray<string>): string;
// eslint-disable-next-line no-redeclare
declare function didYouMean(
subMessage: string,
suggestions: $ReadOnlyArray<string>,
): string;
// eslint-disable-next-line no-redeclare
export default function didYouMean(firstArg, secondArg?) { ... }
I am getting errors on declare also on types :-
C:\Users\aaron\Tests\Babel\generator-test\node_modules\#babel\parser\lib\index.js:730
throw err;
^
SyntaxError: Unexpected token, expected ";" (8:8)
at Parser._raise (C:\Users\aaron\Tests\Babel\generator-test\node_modules\#babel\parser\lib\index.js:723:17)
at Parser.raiseWithData (C:\Users\aaron\Tests\Babel\generator-test\node_modules\#babel\parser\lib\index.js:716:17)
at Parser.raise (C:\Users\aaron\Tests\Babel\generator-test\node_modules\#babel\parser\lib\index.js:710:17)
at Parser.unexpected (C:\Users\aaron\Tests\Babel\generator-test\node_modules\#babel\parser\lib\index.js:8610:16)
at Parser.semicolon (C:\Users\aaron\Tests\Babel\generator-test\node_modules\#babel\parser\lib\index.js:8592:40)
at Parser.parseExpressionStatement (C:\Users\aaron\Tests\Babel\generator-test\node_modules\#babel\parser\lib\index.js:11449:10)
at Parser.parseStatementContent (C:\Users\aaron\Tests\Babel\generator-test\node_modules\#babel\parser\lib\index.js:11050:19)
at Parser.parseStatement (C:\Users\aaron\Tests\Babel\generator-test\node_modules\#babel\parser\lib\index.js:10916:17)
at Parser.parseBlockOrModuleBlockBody (C:\Users\aaron\Tests\Babel\generator-test\node_modules\#babel\parser\lib\index.js:11490:25)
at Parser.parseBlockBody (C:\Users\aaron\Tests\Babel\generator-test\node_modules\#babel\parser\lib\index.js:11477:10) {
loc: Position { line: 8, column: 8 },
pos: 118
}
Github :-
https://github.com/AaronNGray/babel-flow-parser-test
Tag v0 is without package-lock.json
Need to add some extra details which I cannot think of ???

Answer 1

The following works :-
const fs = require('fs');
const babel = require('#babel/core');
if (process.argv.length == 3) {
const filename = process.argv[2];
const source = fs.readFileSync(filename).toString();
const ast = babel.parseSync(source, {
babelrc: false,
configFile: false,
ast: true,
parserOpts: {
plugins: ['flow', 'jsx'],
},
filename,
});
console.log("ast = ", JSON.stringify(ast, null, 2))
}
I would still like to know if the original will work with modification as its the near enough what is specified in the Babel documentation.