typia/src/programmers/internal/metadata_to_pattern.ts

Superfast runtime validators with only one line

import { Metadata } from "../../schemas/metadata/Metadata";

import { PatternUtil } from "../../utils/PatternUtil";

import { template_to_pattern } from "./template_to_pattern";

/**
 * @internal
 */
export const metadata_to_pattern =
  (top: boolean) =>
  (meta: Metadata): string => {
    if (meta.atomics.find((a) => a.type === "string") !== undefined)
      return "(.*)";

    const values: string[] = meta.constants
      .map((c) => {
        if (c.type !== "string") return c.values.map((v) => v.toString());
        return (c.values.map((v) => v.value) as string[]).map((str) =>
          PatternUtil.escape(str),
        );
      })
      .flat();
    for (const a of meta.atomics)
      if (a.type === "number" || a.type === "bigint")
        values.push(PatternUtil.NUMBER);
      else if (a.type === "boolean") values.push(PatternUtil.BOOLEAN);
    for (const { row } of meta.templates)
      values.push("(" + template_to_pattern(false)(row) + ")");

    const pattern: string =
      values.length === 1 ? values[0]! : "(" + values.join("|") + ")";
    return top ? PatternUtil.fix(pattern) : pattern;
  };