dedent.ts

export default function dedent(literals: string): string;
export default function dedent(
  strings: TemplateStringsArray,
  // eslint-disable-next-line @typescript-eslint/no-explicit-any
  ...values: any[]
): string;
export default function dedent(
  strings: string | TemplateStringsArray,
  ...values: string[]
) {
  const raw = typeof strings === "string" ? [strings] : strings.raw;

  // first, perform interpolation
  let result = "";
  for (let i = 0; i < raw.length; i++) {
    result += raw[i]
      // handle escaped newlines, backticks, and interpolation characters
      .replace(/\\`/g, "`")
      .replace(/\\\n[ \t]*/g, "")
      .replace(/\\\$/g, "$")
      .replace(/\\{/g, "{");

    if (i < values.length) {
      result += values[i];
    }
  }

  // now strip indentation
  const lines = result.split("\n");
  let mindent: number | null = null;
  for (const l of lines) {
    const m = l.match(/^(\s+)\S+/);
    if (m) {
      const indent = m[1].length;
      if (!mindent) {
        // this is the first indented line
        mindent = indent;
      } else {
        mindent = Math.min(mindent, indent);
      }
    }
  }

  if (mindent !== null) {
    const m = mindent; // appease TypeScript
    result = lines
      // https://github.com/typescript-eslint/typescript-eslint/issues/7140
      // eslint-disable-next-line @typescript-eslint/prefer-string-starts-ends-with
      .map((l) => (l[0] === " " || l[0] === "\t" ? l.slice(m) : l))
      .join("\n");
  }

  return (
    result
      // dedent eats leading and trailing whitespace too
      .trim()
      // handle escaped newlines at the end to ensure they don't get stripped too
      .replace(/\\n/g, "\n")
  );
}