E0196: new variable shadows existing variable

In JavaScript, const and let create new variables. They do not modify existing variables. It is likely a mistake if a new variable is created with the same name as an existing variable:

let stream;
if (typeof path !== 'undefined') {
  let stream = fs.createWriteStream(path);
} else {
  let stream = fs.createWriteStream("data.txt");
}

const p = inputPath.replace("\\", "/");
const dirPath = path.dirname(p);
while (!fs.isWritable(p)) {
  const p = dirPath + "/";
}

To fix this error, remove the 'let' or 'const' keyword to turn the declaration into an assignment:

let stream;
if (typeof path !== 'undefined') {
  stream = fs.createWriteStream(path);
} else {
  stream = fs.createWriteStream("data.txt");
}

Alternatively, use the variable after declaring it:

const p = inputPath.replace("\\", "/");
const dirPath = path.dirname(p);
while (!fs.isWritable(p)) {
  const p = dirPath + "/";
  fs.remove(p);
  fs.createDirectory(p);
}

Introduced in quick-lint-js version 2.0.0.

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