ensureImport static method

String ensureImport(String source, { required String alias, required String package, })

Ensure the import statement of package with alias exists in source.

sourceにalias付きのpackageのimport文が存在することを保証します。

Implementation

static String ensureImport(
  String source, {
  required String alias,
  required String package,
}) {
  final import = 'import * as $alias from "$package";';
  final existingImport = RegExp(
    '^import \\* as \\w+ from "${RegExp.escape(package)}";\$',
    multiLine: true,
  ).firstMatch(source);
  if (existingImport != null) {
    return source.replaceRange(
      existingImport.start,
      existingImport.end,
      import,
    );
  }
  final imports = RegExp(r"^import .+;$", multiLine: true).allMatches(source);
  if (imports.isEmpty) {
    return "$import\n$source";
  }
  final lastImport = imports.last;
  return source.replaceRange(
    lastImport.end,
    lastImport.end,
    "\n$import",
  );
}