prefer_single_quotes

Unnecessary use of double quotes.

The analyzer produces this diagnostic when a string literal uses double quotes (") when it could use single quotes (') without needing extra escapes and without hurting readability.

The following code produces this diagnostic because the string literal uses double quotes but doesn't need to:

void f(String name) {
  print("Hello $name");
}

Use single quotes in place of double quotes:

void f(String name) {
  print('Hello $name');
}